Implement viewport size override debug setting

Rearrange actor loop to put movement advancement at the end
I don't know why I ever thought this was a separate pass; I think it was just the easiest way to make smooth scrolling work when I first implemented it on like day 2. Turns out it wasn't ever correct and has all manner of subtle implications I'll be sorting out for ages. This does make the turn-based stuff //way// simpler, though.
2020-12-10 18:53:23 -07:00 · 2020-12-10 18:51:40 -07:00 · 2020-12-10 13:54:59 -07:00 · 2020-12-10 13:51:15 -07:00 · 2020-12-10 13:28:40 -07:00 · 2020-12-10 12:48:01 -07:00
47 changed files with 9517 additions and 3070 deletions
@@ -38,7 +38,9 @@ Give it a try, I guess!  [https://c.eev.ee/lexys-labyrinth/](https://c.eev.ee/le

 ## Special thanks

- The incredible nerds who put together the [Chip Wiki](https://wiki.bitbusters.club/) and also reside on the Bit Busters Discord
+- The incredible nerds who put together the [Chip Wiki](https://wiki.bitbusters.club/) and also reside on the Bit Busters Discord, including:
+  - ruben for documenting the CC2 PRNG
+  - The Architect for documenting the CC2 C2G parser
 - Everyone who worked on [Chip's Challenge Level Pack 1](https://wiki.bitbusters.club/Chip%27s_Challenge_Level_Pack_1), the default set of levels
 - [Tile World](https://wiki.bitbusters.club/Tile_World) for being an incredible reference on Lynx mechanics
 - Everyone who contributed music — see [`js/soundtrack.js`](js/soundtrack.js) for a list!
@@ -10,10 +10,11 @@
    <meta name="og:image" content="https://c.eev.ee/lexys-labyrinth/og-preview.png">
    <meta name="og:title" content="Lexy's Labyrinth">
    <meta name="og:description" content="A (work in progress) reimplementation of Chip's Challenge 1 and 2, using entirely free assets.">
+    <meta name="viewport" content="width=device-width, initial-scale=1, user-scalable=no">
 </head>
 <body data-mode="splash">
    <header id="header-main">
-        <img src="icon.png" alt="">
+        <img id="header-icon" src="icon.png" alt="">
        <h1>Lexy's Labyrinth</h1>
        <p>— a game by <a href="https://eev.ee/">eevee</a></p>
        <nav>
@@ -33,51 +34,55 @@
    <header id="header-level">
        <h3 id="level-name">Level 1 — Key Pyramid</h3>
        <nav>
-            <button id="main-prev-level" type="button">←</button>
+            <button id="main-prev-level" type="button">
+                <svg class="svg-icon" viewBox="0 0 16 16" title="previous"><path d="M14,1 2,8 14,14 z"></svg>
+            </button>
            <button id="main-choose-level" type="button">Level select</button>
-            <button id="main-next-level" type="button">→</button>
+            <button id="main-next-level" type="button">
+                <svg class="svg-icon" viewBox="0 0 16 16" title="next"><path d="M2,1 14,8 2,14 z"></svg>
+            </button>
        </nav>
    </header>
    <main id="splash">
+        <div class="drag-overlay"></div>
        <header>
            <h1><img src="og-preview.png" alt="">Lexy's Labyrinth</h1>
+            <p>an unapproved Chip's Challenge emulator</p>
        </header>
        <section id="splash-intro">
            <p><strong>Welcome</strong> to Lexy's Labyrinth, an open source puzzle game that is curiously similar to — but legally distinct from — the Atari classic <a href="https://en.wikipedia.org/wiki/Chip%27s_Challenge">Chip's Challenge</a>!</p>
-            <p>(This is a Chip's Challenge <em>emulator</em>, designed to be an accessible way to play community-made levels with free assets.  It's 99% compatible with Chip's Challenge 1, and support for Chip's Challenge 2 is underway.  But you can safely ignore all that and treat this as its own game.)</p>
-            <p>Please note that <em>levels themselves</em> may contain hints or lore referring to a guy named Chip collecting computer chips, even though you are clearly a fox named Lexy collecting hearts.  Weird, right?  Sorry for any confusion!</p>
-            <p>Pick a level pack to get started!  You can also get more technical details or report bugs on <a href="https://github.com/eevee/lexys-labyrinth">GitHub</a>, find out more about Chip's Challenge via the <a href="https://bitbusters.club/">Bit Busters Club</a> fansite, or support this endeavor (and other things I do) via <a href="https://www.patreon.com/eevee">Patreon</a>!</p>
-            <!-- TODO i want to make clear this is a chip's challenge emulator without bogging people down too much about what that means -->
+            <p>Pick a level pack to get started!  You can also load and play any levels you've got lying around, or brave the level editor and make one of your own.</p>
+            <p>If you're not familiar with the game, read up on <a href="https://github.com/eevee/lexys-labyrinth/wiki/How-To-Play">how to play</a>.  You can also get more technical details or report bugs on <a href="https://github.com/eevee/lexys-labyrinth">GitHub</a>, find out more about Chip's Challenge via the <a href="https://bitbusters.club/">Bit Busters Club</a> fansite, or support this endeavor (and other things I do) on <a href="https://www.patreon.com/eevee">Patreon</a>.</p>
        </section>

        <section id="splash-stock-levels">
-            <h2>Just play something</h2>
+            <h2>Play community levels</h2>
            <!-- populated by js -->
        </section>

        <section id="splash-upload-levels">
-            <h2>Other levels</h2>
-            <p>You can play <code>CHIPS.DAT</code> from the original Microsoft version, any custom levels you have lying around, or perhaps ones you found on the <a href="https://sets.bitbusters.club/">Bit Busters Club set list</a>!</p>
-            <!-- TODO explain how to find chips.dat or steam folder -->
-            <!-- TODO drag and drop? -->
-            <input id="splash-upload" type="file" accept=".dat,.ccl,.c2m,.ccs">
-            <button type="button" id="splash-upload-button" class="button-big">Open a local level<!-- TODO: <br>(or drag and drop a file into this window) --></button>
-            <p>Supports both the old Microsoft <code>CHIPS.DAT</code> format and the Steam <code>C2M</code> format.</p>
-            <p>Does <em>not</em> yet support the Steam <code>C2G</code> format, so tragically, the original Steam levels can only be played one at a time.  This should be fixed soon!</p>
-            <!--
+            <h2>Load other levels</h2>
+            <p>Load and play any levels you have on hand, including the original levels.  Supports CCL/DAT, C2G, and individual C2Ms (though scores aren't saved for those).  Find more on the <a href="https://sets.bitbusters.club/">Bit Busters Club set list</a>.</p>
+            <!-- TODO zip files! -->
+            <p>You can also drag and drop files or directories into this window.</p>
+            <input id="splash-upload-file" type="file" accept=".dat,.ccl,.c2m,.ccs" multiple>
+            <input id="splash-upload-dir" type="file" webkitdirectory>
+            <button type="button" id="splash-upload-file-button" class="button-big">Load files</button>
+            <button type="button" id="splash-upload-dir-button" class="button-big">Load directory</button>
+            <p>If you still have the original Microsoft "BOWEP" game lying around, you can play the Chip's Challenge 1 levels by loading <code>CHIPS.DAT</code>.</p>
            <p>If you own the Steam versions of <a href="https://store.steampowered.com/app/346850/Chips_Challenge_1/">Chip's Challenge 1</a> (<em>free!</em>) or <a href="https://store.steampowered.com/app/348300/Chips_Challenge_2/">Chip's Challenge 2</a> ($5 last I checked), you can play those too, even on Linux or Mac:</p>
            <ol class="normal-list">
                <li>Right-click the game in Steam and choose <em>Properties</em>.  On the <em>Local Files</em> tab, click <em>Browse local files</em>.</li>
                <li>Open the <code>data</code> folder, then <code>games</code>.</li>
-                <li>You should see either a <code>cc1</code> or <code>cc2</code> folder.  Drag it into this window.</li>
+                <li>You should see either a <code>cc1</code> or <code>cc2</code> folder.  Drag it into this window, or load it with the button above.</li>
            </ol>
-            -->
        </section>

        <section id="splash-your-levels">
            <h2>Make your own (WIP lol)</h2>
-            <p>Please note that the level editor is <strong>extremely</strong> unfinished, and can't even save yet.</p>
-            <p><button type="button" id="splash-create-level" class="button-big">Create a level</button></p>
+            <p>Please note that the level editor is <strong>very</strong> unfinished, and doesn't even have undo yet.  It may eat your work!  Beware!</p>
+            <p><button type="button" id="splash-create-pack" class="button-big">New pack</button></p>
+            <p><button type="button" id="splash-create-level" class="button-big">New scratch level<br>(won't be saved!)</button></p>
        </section>
    </main>
    <main id="player" hidden>
@@ -104,6 +109,88 @@
            </div>
            <div class="inventory"></div>
        </section>
+        <form id="player-debug">
+            <div class="-time">
+                <table class="-time-controls">
+                    <tr>
+                        <td><button type="button" class="-time-button" data-dt="-1">← 1 tic</button></td>
+                        <td id="player-debug-time-tics">0</td>
+                        <td>tics</td>
+                        <td><button type="button" class="-time-button" data-dt="1">1 tic →</button></td>
+                    </tr>
+                    <tr>
+                        <td><button type="button" class="-time-button" data-dt="-4">← 1 move</button></td>
+                        <td id="player-debug-time-moves">0</td>
+                        <td>moves</td>
+                        <td><button type="button" class="-time-button" data-dt="4">1 move →</button></td>
+                    </tr>
+                    <tr>
+                        <td><button type="button" class="-time-button" data-dt="-20">← 1 s</button></td>
+                        <td id="player-debug-time-secs">0</td>
+                        <td>seconds</td>
+                        <td><button type="button" class="-time-button" data-dt="20">1 s →</button></td>
+                    </tr>
+                </table>
+                <p>Game speed:
+                    <select name="speed">
+                        <option value="6">6× — 120 tics per second</option>
+                        <option value="3">3× — 60 tics per second</option>
+                        <option value="2">2× — 40 tics per second</option>
+                        <option value="3/2">1½× — 30 tics per second</option>
+                        <option value="1" selected>1× — 20 tics per second</option>
+                        <option value="1/2">½× — 10 tics per second</option>
+                        <option value="1/3">⅓× — 6⅔ tics per second</option>
+                        <option value="1/4">¼× — 5 tics per second</option>
+                    </select>
+                </p>
+            </div>
+            <div class="input"></div>
+            <div class="-options">
+                <p> Viewport size:
+                    <select id="player-debug-viewport">
+                        <option value="default" selected>Level default (9 or 10)</option>
+                        <option value="12">12 × 12</option>
+                        <option value="16">16 × 16</option>
+                        <option value="24">24 × 24</option>
+                        <option value="32">32 × 32</option>
+                        <option value="max">Entire level</option>
+                    </select>
+                </p>
+                <ul>
+                    <li><label><input type="checkbox" name="show_actor_bboxes"> Show actor bounding boxes</label></li>
+                    <li><label><input type="checkbox" name="disable_interpolation"> Disable interpolation</label></li>
+                    <!--
+                    <li><label><input type="checkbox" disabled> Show actor info</label></li>
+                    <li><label><input type="checkbox" disabled> Freeze time for everything else</label></li>
+                    <li><label><input type="checkbox" disabled> Player is immortal</label></li>
+                    <li><label><input type="checkbox" disabled> Player ignores collision</label></li>
+                    <li><label><input type="checkbox" disabled> Player levitates</label></li>
+                    -->
+                </ul>
+                <p>(Middle-click to teleport.)</p>
+            </div>
+            <div class="-inventory">
+                <!-- populated in js -->
+            </div>
+            <div class="-buttons">
+                <!-- populated in js -->
+            </div>
+
+            <!-- TODO?
+                - inspect with mouse
+                    - list of actors, or currently pointed-to actor?
+                - activate something manually?
+                - click a button ingame?
+                - pan viewport (like editor)
+                - show connections, directions, other editor features
+                - look under anything
+
+                - other game info?
+                    - count tiles?
+                    - total hearts?
+                    - total bonus flags?
+            -->
+        </form>
        <div id="player-music">
            <div id="player-music-left">
                🎵 <a id="player-music-title">title</a> by <a id="player-music-author">author</a>
@@ -116,28 +203,39 @@
        </div>
        <div class="controls">
            <div class="play-controls">
-                <button class="control-pause" type="button">Pause (p)</button>
-                <button class="control-restart" type="button">Restart</button>
-                <button class="control-undo" type="button">Undo</button>
-                <button class="control-rewind" type="button">Rewind (z)</button>
+                <button class="control-pause" type="button">
+                    <svg class="svg-icon" viewBox="0 0 16 16" title="pause"><path d="M2,1 h4 v14 h-4 z M10,1 h4 v14 h-4 z"></svg>
+                    <span class="keyhint">p</span></button>
+                <button class="control-restart" type="button">
+                    <svg class="svg-icon" viewBox="0 0 16 16" title="restart"><path d="M13,13 A 7,7 270 1,1 13,3 L15,1 15,7 9,7 11,5 A 4,4 270 1,0 11,11 z"></svg>
+                    </button>
+                <button class="control-undo" type="button">
+                    <svg class="svg-icon" viewBox="0 0 16 16" title="undo"><path d="M6,5 6,2 1,7 6,12 6,9 A 10,10 60 0,1 15,12 A 10,10 90 0,0 6,5"></svg>
+                    </button>
+                <button class="control-rewind" type="button">
+                    <svg class="svg-icon" viewBox="0 0 16 16" title="rewind"><path d="M1,8 7,2 7,14 z M9,8 15,2 15,14 z"></svg>
+                    <span class="keyhint">z</span></button>
+                <label><input class="control-turn-based" type="checkbox"> Turn-based mode</label>
            </div>
-            <div class="demo-controls">
-                <button class="demo-play" type="button">View replay</button>
-                <button class="demo-step-1" type="button">Step 1 tic</button>
-                <button class="demo-step-4" type="button">Step 1 move</button>
-                <div class="input"></div>
+            <div class="actions">
+                <button class="action-drop" type="button">
+                    <svg class="svg-icon" viewBox="0 0 16 16" title="pause"><path d="M6,0 h4 v9 h3 l-5,5 h7 v2 h-14 v-2 h7 l-5,-5 h3"></svg>
+                    drop <span class="keyhint">q</span></button>
+                <button class="action-cycle" type="button">
+                    <svg class="svg-icon" viewBox="0 0 16 16" title="pause">
+                        <path d="M2,3 H11 V1 l4,4 -4,4 V7 H2 Z"></path>
+                        <path d="M14,9 H5 V7 l-4,4 4,4 v-2 h9 z"></path>
+                    </svg>
+                    cycle <span class="keyhint">e</span></button>
+                <button class="action-swap" type="button">
+                    <svg class="svg-icon" viewBox="0 0 16 16" title="pause">
+                        <path d="m 7,1 h 2 l 1,1 V 6 L 9,7 v 4 L 8,11.5 7,11 V 7 L 6,6 V 2 Z"></path>
+                        <path d="M 8,13 13,11 8,9 3,11 Z m 0,2 7,-3 V 11 L 8,8 1,11 v 1 z"></path>
+                        <ellipse cx="5.5" cy="11" rx="0.75" ry="0.5"></ellipse>
+                    </svg>
+                    switch <span class="keyhint">c</span></button>
            </div>
        </div>
-        <!-- TODO debug panel?
-        - current tic
-        - list of actors, or currently pointed-to actor?
-        <div class="debug">
-            <button>« 4 tics</button>
-            <button>« 1 tic</button>
-            <button>1 tic »</button>
-            <button>4 tics »</button>
-        </div>
-        -->
    </main>
    <main id="editor" hidden>
        <header>
@@ -151,9 +249,15 @@
            also deal with levels vs level /packs/ somehow, not sure how that'll work (including downloading them, yeargh?)
            -->
        </header>
-        <div class="level"><!-- level canvas and any overlays go here --></div>
-        <div class="controls">
-            <button id="editor-share-url" type="button">Share?</button>
+        <div class="editor-canvas">
+            <div class="-container">
+                <!-- level canvas and any overlays go here -->
+                <!-- the container is to allow them to scroll as a single unit -->
+            </div>
+        </div>
+        <nav class="controls">
+            <div id="editor-tile">
+            </div>
            <!--
            <p style>
                Tip: Right click to color drop.<br>
@@ -178,7 +282,7 @@
            map size
            </pre>
            -->
-        </div>
+        </nav>
        <div class="palette"></div>
        <!-- TODO:
        controls
@@ -4,6 +4,7 @@ export const DIRECTIONS = {
    north: {
        movement: [0, -1],
        bit: 0x01,
+        index: 0,
        action: 'up',
        left: 'west',
        right: 'east',
@@ -12,6 +13,7 @@ export const DIRECTIONS = {
    south: {
        movement: [0, 1],
        bit: 0x04,
+        index: 2,
        action: 'down',
        left: 'east',
        right: 'west',
@@ -20,6 +22,7 @@ export const DIRECTIONS = {
    west: {
        movement: [-1, 0],
        bit: 0x08,
+        index: 3,
        action: 'left',
        left: 'south',
        right: 'north',
@@ -28,9 +31,49 @@ export const DIRECTIONS = {
    east: {
        movement: [1, 0],
        bit: 0x02,
+        index: 1,
        action: 'right',
        left: 'north',
        right: 'south',
        opposite: 'west',
    },
 };
+// Should match the bit ordering above, and CC2's order
+export const DIRECTION_ORDER = ['north', 'east', 'south', 'west'];
+
+// TODO cc2 order is: swivel, thinwalls, canopy (and yes you can have them all in the same tile)
+export const DRAW_LAYERS = {
+    terrain: 0,
+    item: 1,
+    item_mod: 2,
+    actor: 3,
+    overlay: 4,
+    MAX: 5,
+};
+
+export const COLLISION = {
+    player1:            0x0001,
+    player2:            0x0002,
+    player:             0x0003,
+
+    block_cc1:          0x0004,
+    block_cc2:          0x0008,  // ice + directional
+
+    // Monsters are a little complicated, because some of them have special rules, e.g. fireballs
+    // aren't blocked by fire.
+    // For a monster's MASK, you should use ONLY ONE of these specific monster bits (if
+    // appropriate), OR the generic bit -- DO NOT combine them!
+    monster_generic:    0x0100,
+    fireball:           0x0200,
+    bug:                0x0400,
+    rover:              0x1000,
+    ghost:              0x8000,
+    // For a tile's COLLISION, use one of these bit combinations
+    monster_solid:      0x7f00,  // everything but ghost
+    monster_any:        0xff00,  // everything including ghost
+
+    // Combo masks used for matching
+    all_but_ghost:      0xffff & ~0x8000,
+    all_but_player:     0xffff & ~0x0003,
+    all:                0xffff,
+};
@@ -0,0 +1,253 @@
+import { TransientOverlay } from './main-base.js';
+import { mk, mk_svg } from './util.js';
+
+// FIXME could very much stand to have a little animation when appearing
+class TileEditorOverlay extends TransientOverlay {
+    constructor(conductor) {
+        let root = mk('form.editor-popup-tile-editor');
+        super(conductor, root);
+        this.editor = conductor.editor;
+        this.tile = null;
+    }
+
+    edit_tile(tile) {
+        this.tile = tile;
+    }
+
+    static configure_tile_defaults(tile) {
+        // FIXME maybe this should be on the tile type, so it functions as documentation there?
+    }
+}
+
+class LetterTileEditor extends TileEditorOverlay {
+    constructor(conductor) {
+        super(conductor);
+
+        this.root.append(mk('h3', "Letter tile"));
+        let list = mk('ol.editor-letter-tile-picker');
+        this.root.append(list);
+        this.glyph_elements = {};
+        let add = glyph => {
+            let input = mk('input', {type: 'radio', name: 'glyph', value: glyph});
+            this.glyph_elements[glyph] = input;
+            let item = mk('li', mk('label', input, mk('span.-glyph', glyph)));
+            list.append(item);
+        };
+        let arrows = ["⬆", "➡", "⬇", "⬅"];
+        for (let c = 32; c < 96; c++) {
+            let glyph = String.fromCharCode(c);
+            add(glyph);
+            // Add the arrows to the ends of the rows
+            if (c % 16 === 15) {
+                add(arrows[(c - 47) / 16]);
+            }
+        }
+
+        list.addEventListener('change', ev => {
+            if (this.tile) {
+                this.tile.overlaid_glyph = this.root.elements['glyph'].value;
+                this.editor.mark_tile_dirty(this.tile);
+            }
+        });
+    }
+
+    edit_tile(tile) {
+        super.edit_tile(tile);
+        this.root.elements['glyph'].value = tile.overlaid_glyph;
+    }
+
+    static configure_tile_defaults(tile) {
+        tile.type.populate_defaults(tile);
+    }
+}
+
+class HintTileEditor extends TileEditorOverlay {
+    constructor(conductor) {
+        super(conductor);
+
+        this.root.append(mk('h3', "Hint text"));
+        this.text = mk('textarea.editor-hint-tile-text');
+        this.root.append(this.text);
+        this.text.addEventListener('input', ev => {
+            if (this.tile) {
+                this.tile.hint_text = this.text.value;
+            }
+        });
+    }
+
+    edit_tile(tile) {
+        super.edit_tile(tile);
+        this.text.value = tile.hint_text ?? "";
+    }
+
+    static configure_tile_defaults(tile) {
+        tile.hint_text = "";
+    }
+}
+
+class FrameBlockTileEditor extends TileEditorOverlay {
+    constructor(conductor) {
+        super(conductor);
+
+        let svg_icons = [];
+        for (let center of [[16, 0], [16, 16], [0, 16], [0, 0]]) {
+            let symbol = mk_svg('svg', {viewBox: '0 0 16 16'},
+                mk_svg('circle', {cx: center[0], cy: center[1], r: 3}),
+                mk_svg('circle', {cx: center[0], cy: center[1], r: 13}),
+            );
+            svg_icons.push(symbol);
+        }
+        svg_icons.push(mk_svg('svg', {viewBox: '0 0 16 16'},
+            mk_svg('rect', {x: -2, y: 3, width: 20, height: 10}),
+        ));
+        svg_icons.push(mk_svg('svg', {viewBox: '0 0 16 16'},
+            mk_svg('rect', {x: 3, y: -2, width: 10, height: 20}),
+        ));
+
+        this.root.append(mk('h3', "Arrows"));
+        let arrow_list = mk('ol.editor-directional-block-tile-arrows.editor-tile-editor-svg-parts');
+        // Arrange the arrows in a grid
+        for (let [direction, icon] of [
+                [null, mk_svg('path', {d: 'M 8,16 v -8 h 8'})],
+                ['north', mk_svg('path', {d: 'M 0,12 h 16 l -8,-8 z'})],
+                [null, mk_svg('path', {d: 'M 0,8 h 8 v 8'})],
+                ['west', mk_svg('path', {d: 'M 12,16 v -16 l -8,8 z'})],
+                [null, null],
+                ['east', mk_svg('path', {d: 'M 4,0 v 16 l 8,-8 z'})],
+                [null, mk_svg('path', {d: 'M 16,8 h -8 v -8'})],
+                ['south', mk_svg('path', {d: 'M 16,4 h -16 l 8,8 z'})],
+                [null, mk_svg('path', {d: 'M 8,0 v 8 h -8'})],
+        ]) {
+            let li = mk('li');
+            let svg;
+            if (icon) {
+                svg = mk_svg('svg', {viewBox: '0 0 16 16'}, icon);
+            }
+            if (direction === null) {
+                if (svg) {
+                    li.append(svg);
+                }
+            }
+            else {
+                let input = mk('input', {type: 'checkbox', name: 'direction', value: direction});
+                li.append(mk('label', input, svg));
+            }
+            arrow_list.append(li);
+        }
+        arrow_list.addEventListener('change', ev => {
+            if (! this.tile)
+                return;
+
+            if (ev.target.checked) {
+                this.tile.arrows.add(ev.target.value);
+            }
+            else {
+                this.tile.arrows.delete(ev.target.value);
+            }
+            this.editor.mark_tile_dirty(this.tile);
+        });
+        this.root.append(arrow_list);
+    }
+
+    edit_tile(tile) {
+        super.edit_tile(tile);
+
+        for (let input of this.root.elements['direction']) {
+            input.checked = tile.arrows.has(input.value);
+        }
+    }
+
+    static configure_tile_defaults(tile) {
+    }
+}
+
+class RailroadTileEditor extends TileEditorOverlay {
+    constructor(conductor) {
+        super(conductor);
+
+        let svg_icons = [];
+        for (let center of [[16, 0], [16, 16], [0, 16], [0, 0]]) {
+            let symbol = mk_svg('svg', {viewBox: '0 0 16 16'},
+                mk_svg('circle', {cx: center[0], cy: center[1], r: 3}),
+                mk_svg('circle', {cx: center[0], cy: center[1], r: 13}),
+            );
+            svg_icons.push(symbol);
+        }
+        svg_icons.push(mk_svg('svg', {viewBox: '0 0 16 16'},
+            mk_svg('rect', {x: -2, y: 3, width: 20, height: 10}),
+        ));
+        svg_icons.push(mk_svg('svg', {viewBox: '0 0 16 16'},
+            mk_svg('rect', {x: 3, y: -2, width: 10, height: 20}),
+        ));
+
+        this.root.append(mk('h3', "Tracks"));
+        let track_list = mk('ul.editor-railroad-tile-tracks.editor-tile-editor-svg-parts');
+        // Shown as two rows, this puts the straight parts first and the rest in a circle
+        let track_order = [4, 1, 2, 5, 0, 3];
+        for (let i of track_order) {
+            let input = mk('input', {type: 'checkbox', name: 'track', value: i});
+            track_list.append(mk('li', mk('label', input, svg_icons[i])));
+        }
+        track_list.addEventListener('change', ev => {
+            if (this.tile) {
+                let bit = 1 << ev.target.value;
+                if (ev.target.checked) {
+                    this.tile.tracks |= bit;
+                }
+                else {
+                    this.tile.tracks &= ~bit;
+                }
+                this.editor.mark_tile_dirty(this.tile);
+            }
+        });
+        this.root.append(track_list);
+
+        this.root.append(mk('h3', "Switch"));
+        let switch_list = mk('ul.editor-railroad-tile-tracks.--switch');
+        for (let i of track_order) {
+            let input = mk('input', {type: 'radio', name: 'switch', value: i});
+            switch_list.append(mk('li', mk('label', input, svg_icons[i].cloneNode(true))));
+        }
+        // TODO if they remove a track it should change the switch
+        // TODO if they pick a track that's missing it should add it
+        switch_list.addEventListener('change', ev => {
+            if (this.tile) {
+                this.tile.track_switch = ev.target.value;
+                this.editor.mark_tile_dirty(this.tile);
+            }
+        });
+        this.root.append(switch_list);
+
+        // TODO need a way to set no actor at all
+        // TODO initial actor facing (maybe only if there's an actor in the cell)
+    }
+
+    edit_tile(tile) {
+        super.edit_tile(tile);
+
+        for (let input of this.root.elements['track']) {
+            input.checked = !! (tile.tracks & (1 << input.value));
+        }
+
+        if (tile.track_switch === null) {
+            this.root.elements['switch'].value = '';
+        }
+        else {
+            this.root.elements['switch'].value = tile.track_switch;
+        }
+    }
+
+    static configure_tile_defaults(tile) {
+    }
+}
+
+export const TILES_WITH_PROPS = {
+    floor_letter: LetterTileEditor,
+    hint: HintTileEditor,
+    frame_block: FrameBlockTileEditor,
+    railroad: RailroadTileEditor,
+    // TODO various wireable tiles (hmm not sure how that ui works)
+    // TODO initial value of counter
+    // TODO cloner arrows
+    // TODO later, custom floor/wall selection
+};
@@ -0,0 +1,86 @@
+import * as util from './util.js';
+
+export class StoredCell extends Array {
+}
+
+export class StoredLevel {
+    constructor(number) {
+        // TODO still not sure this belongs here
+        this.number = number;  // one-based
+        this.title = '';
+        this.author = '';
+        this.password = null;
+        this.hint = '';
+        this.chips_required = 0;
+        this.time_limit = 0;
+        this.viewport_size = 9;
+        this.extra_chunks = [];
+        this.use_cc1_boots = false;
+        this.use_ccl_compat = false;
+        // 0 - deterministic (PRNG + simple convolution)
+        // 1 - 4 patterns (default; PRNG + rotating through 0-3)
+        // 2 - extra random (like deterministic, but initial seed is "actually" random)
+        this.blob_behavior = 1;
+
+        this.size_x = 0;
+        this.size_y = 0;
+        this.linear_cells = [];
+
+        // Maps of button positions to trap/cloner positions, as scalar indexes
+        // in the linear cell list
+        // TODO merge these imo
+        this.has_custom_connections = false;
+        this.custom_trap_wiring = {};
+        this.custom_cloner_wiring = {};
+
+        // New LL feature: custom camera regions, as lists of {x, y, width, height}
+        this.camera_regions = [];
+    }
+
+    scalar_to_coords(n) {
+        return [n % this.size_x, Math.floor(n / this.size_x)];
+    }
+
+    coords_to_scalar(x, y) {
+        return x + y * this.size_x;
+    }
+
+    check() {
+    }
+}
+
+export class StoredPack {
+    constructor(identifier, level_loader) {
+        this.identifier = identifier;
+        this.title = "";
+        this._level_loader = level_loader;
+
+        // Simple objects containing keys that are usually:
+        // title: level title
+        // index: level index, used internally only
+        // number: level number (may not match index due to C2G shenanigans)
+        // error: any error received while loading the level
+        // bytes: Uint8Array of the encoded level data
+        this.level_metadata = [];
+    }
+
+    // TODO this may or may not work sensibly when correctly following a c2g
+    load_level(index) {
+        let meta = this.level_metadata[index];
+        if (! meta)
+            throw new util.LLError(`No such level number ${index}`);
+        if (meta.error)
+            throw meta.error;
+
+        if (meta.stored_level) {
+            // The editor stores inflated levels at times, so respect that
+            return meta.stored_level;
+        }
+        else {
+            // Otherwise, attempt to load the level
+            return this._level_loader(meta);
+        }
+    }
+}
+
+export const StoredGame = StoredPack;
@@ -1,5 +1,6 @@
-import * as util from './format-util.js';
+import * as format_base from './format-base.js';
 import TILE_TYPES from './tiletypes.js';
+import * as util from './util.js';

 const TILE_ENCODING = {
    0x00: 'floor',
@@ -119,18 +120,70 @@ const TILE_ENCODING = {
    0x6f: ['player', 'east'],
 };

-function parse_level(buf, number) {
-    let level = new util.StoredLevel(number);
+function decode_password(bytes, start, len) {
+    let password = [];
+    for (let i = 0; i < len; i++) {
+        password.push(bytes[start + i] ^ 0x99);
+    }
+    return String.fromCharCode.apply(null, password);
+}
+
+export function parse_level_metadata(bytes) {
+    let meta = {};
+
+    let view = new DataView(bytes.buffer, bytes.byteOffset, bytes.byteLength);
+
+    // Level number; rest of level header is unused
+    meta.number = view.getUint16(0, true);
+
+    // Map layout
+    // Same structure twice, for the two layers
+    let p = 8;
+    for (let l = 0; l < 2; l++) {
+        let layer_length = view.getUint16(p, true);
+        p += 2 + layer_length;
+    }
+
+    // Optional metadata fields
+    let meta_length = view.getUint16(p, true);
+    p += 2;
+    let end = p + meta_length;
+    while (p < end) {
+        // Common header
+        let field_type = view.getUint8(p, true);
+        let field_length = view.getUint8(p + 1, true);
+        p += 2;
+        if (field_type === 0x03) {
+            // Title, including trailing NUL
+            meta.title = util.string_from_buffer_ascii(bytes, p, field_length - 1);
+        }
+        else if (field_type === 0x06) {
+            // Password, with trailing NUL, and XORed with 0x99 (???)
+            meta.password = decode_password(bytes, p, field_length - 1);
+        }
+        else if (field_type === 0x07) {
+            // Hint, including trailing NUL, of course
+            meta.hint = util.string_from_buffer_ascii(bytes, p, field_length - 1);
+        }
+        p += field_length;
+    }
+
+    return meta;
+}
+
+function parse_level(bytes, number) {
+    let level = new format_base.StoredLevel(number);
+    level.has_custom_connections = true;
+    level.use_ccl_compat = true;
    // Map size is always fixed as 32x32 in CC1
    level.size_x = 32;
    level.size_y = 32;
    for (let i = 0; i < 1024; i++) {
-        level.linear_cells.push(new util.StoredCell);
+        level.linear_cells.push(new format_base.StoredCell);
    }
    level.use_cc1_boots = true;

-    let view = new DataView(buf);
-    let bytes = new Uint8Array(buf);
+    let view = new DataView(bytes.buffer, bytes.byteOffset, bytes.byteLength);

    // Header
    let level_number = view.getUint16(0, true);
@@ -161,7 +214,7 @@ function parse_level(buf, number) {
            // TODO could be more forgiving for goofy levels doing goofy things
            if (! spec) {
                let [x, y] = level.scalar_to_coords(c);
-                throw new Error(`Invalid tile byte 0x${tile_byte.toString(16)} at (${x}, ${y}) in level ${number}`);
+                throw new Error(`Invalid tile byte 0x${tile_byte.toString(16)} at (${x}, ${y})`);
            }

            let name, direction;
@@ -225,11 +278,11 @@ function parse_level(buf, number) {
        }
        else if (field_type === 0x03) {
            // Title, including trailing NUL
-            level.title = util.string_from_buffer_ascii(buf.slice(p, p + field_length - 1));
+            level.title = util.string_from_buffer_ascii(bytes, p, field_length - 1);
        }
        else if (field_type === 0x04) {
            // Trap linkages (MSCC only, not in Lynx or CC2)
-            let field_view = new DataView(buf.slice(p, p + field_length));
+            let field_view = new DataView(bytes.buffer, bytes.byteOffset + p, field_length);
            let q = 0;
            while (q < field_length) {
                let button_x = field_view.getUint16(q + 0, true);
@@ -243,7 +296,7 @@ function parse_level(buf, number) {
        }
        else if (field_type === 0x05) {
            // Cloner linkages (MSCC only, not in Lynx or CC2)
-            let field_view = new DataView(buf.slice(p, p + field_length));
+            let field_view = new DataView(bytes.buffer, bytes.byteOffset + p, field_length);
            let q = 0;
            while (q < field_length) {
                let button_x = field_view.getUint16(q + 0, true);
@@ -255,16 +308,12 @@ function parse_level(buf, number) {
            }
        }
        else if (field_type === 0x06) {
-            // Password, with trailing NUL, and otherwise XORed with 0x99 (?!)
-            let password = [];
-            for (let i = 0; i < field_length - 1; i++) {
-                password.push(view.getUint8(p + i, true) ^ 0x99);
-            }
-            level.password = String.fromCharCode.apply(null, password);
+            // Password, with trailing NUL, and otherwise XORed with 0x99 (???)
+            level.password = decode_password(bytes, p, field_length - 1);
        }
        else if (field_type === 0x07) {
            // Hint, including trailing NUL, of course
-            level.hint = util.string_from_buffer_ascii(buf.slice(p, p + field_length - 1));
+            level.hint = util.string_from_buffer_ascii(bytes, p, field_length - 1);
        }
        else if (field_type === 0x08) {
            // Password, but not encoded
@@ -280,8 +329,13 @@ function parse_level(buf, number) {
    return level;
 }

+// This thin wrapper is passed to StoredGame as the parser function
+function _parse_level_from_stored_meta(meta) {
+    return parse_level(meta.bytes, meta.number);
+}
+
 export function parse_game(buf) {
-    let game = new util.StoredGame;
+    let game = new format_base.StoredGame(null, _parse_level_from_stored_meta);

    let full_view = new DataView(buf);
    let magic = full_view.getUint32(0, true);
@@ -303,11 +357,19 @@ export function parse_game(buf) {
    let p = 6;
    for (let l = 1; l <= level_count; l++) {
        let length = full_view.getUint16(p, true);
-        let level_buf = buf.slice(p + 2, p + 2 + length);
+        let bytes = new Uint8Array(buf, p + 2, length);
        p += 2 + length;

-        let level = parse_level(level_buf, l);
-        game.levels.push(level);
+        let meta;
+        try {
+            meta = parse_level_metadata(bytes);
+        }
+        catch (e) {
+            meta = {error: e};
+        }
+        meta.index = l - 1;
+        meta.bytes = bytes;
+        game.level_metadata.push(meta);
    }

    return game;
@@ -1,47 +0,0 @@
-export function string_from_buffer_ascii(buf) {
-    return String.fromCharCode.apply(null, new Uint8Array(buf));
-}
-
-export class StoredCell extends Array {
-}
-
-export class StoredLevel {
-    constructor(number) {
-        this.number = number;  // one-based
-        this.title = '';
-        this.password = null;
-        this.hint = '';
-        this.chips_required = 0;
-        this.time_limit = 0;
-        this.viewport_size = 9;
-        this.extra_chunks = [];
-        this.use_cc1_boots = false;
-
-        this.size_x = 0;
-        this.size_y = 0;
-        this.linear_cells = [];
-
-        // Maps of button positions to trap/cloner positions, as scalar indexes
-        // in the linear cell list
-        this.custom_trap_wiring = {};
-        this.custom_cloner_wiring = {};
-    }
-
-    scalar_to_coords(n) {
-        return [n % this.size_x, Math.floor(n / this.size_x)];
-    }
-
-    coords_to_scalar(x, y) {
-        return x + y * this.size_x;
-    }
-
-    check() {
-    }
-}
-
-export class StoredGame {
-    constructor(identifier) {
-        this.identifier = identifier;
-        this.levels = [];
-    }
-}
@@ -0,0 +1,129 @@
+import { mk, mk_svg, walk_grid } from './util.js';
+
+// Superclass for the main display modes: the player, the editor, and the splash screen
+export class PrimaryView {
+    constructor(conductor, root) {
+        this.conductor = conductor;
+        this.root = root;
+        this.active = false;
+        this._done_setup = false;
+    }
+
+    setup() {}
+
+    activate() {
+        this.root.removeAttribute('hidden');
+        this.active = true;
+        if (! this._done_setup) {
+            this.setup();
+            this._done_setup = true;
+        }
+    }
+
+    deactivate() {
+        this.root.setAttribute('hidden', '');
+        this.active = false;
+    }
+}
+
+// Stackable modal overlay of some kind, usually a dialog
+export class Overlay {
+    constructor(conductor, root) {
+        this.conductor = conductor;
+        this.root = root;
+
+        // Don't propagate clicks on the root element, so they won't trigger a
+        // parent overlay's automatic dismissal
+        this.root.addEventListener('click', ev => {
+            ev.stopPropagation();
+        });
+        // Block any window-level key handlers from firing when we type
+        this.root.addEventListener('keydown', ev => {
+            ev.stopPropagation();
+        });
+    }
+
+    open() {
+        // FIXME ah, but keystrokes can still go to the game, including
+        // spacebar to begin it if it was waiting.  how do i completely disable
+        // an entire chunk of the page?
+        if (this.conductor.player.state === 'playing') {
+            this.conductor.player.set_state('paused');
+        }
+
+        let overlay = mk('div.overlay', this.root);
+        document.body.append(overlay);
+
+        // Remove the overlay when clicking outside the element
+        overlay.addEventListener('click', ev => {
+            this.close();
+        });
+
+        return overlay;
+    }
+
+    close() {
+        this.root.closest('.overlay').remove();
+    }
+}
+
+// Overlay styled like a popup of some sort
+export class TransientOverlay extends Overlay {
+    open() {
+        // TODO i don't like how vaguely arbitrary this feels.
+        let overlay = super.open();
+        overlay.classList.add('--transient');
+        return overlay;
+    }
+}
+
+// Overlay styled like a dialog box
+export class DialogOverlay extends Overlay {
+    constructor(conductor) {
+        super(conductor, mk('form.dialog'));
+
+        this.root.append(
+            this.header = mk('header'),
+            this.main = mk('section'),
+            this.footer = mk('footer'),
+        );
+    }
+
+    set_title(title) {
+        this.header.textContent = '';
+        this.header.append(mk('h1', {}, title));
+    }
+
+    add_button(label, onclick) {
+        let button = mk('button', {type: 'button'}, label);
+        button.addEventListener('click', onclick);
+        this.footer.append(button);
+    }
+}
+
+// Yes/no popup dialog
+export class ConfirmOverlay extends DialogOverlay {
+    constructor(conductor, message, what) {
+        super(conductor);
+        this.set_title("just checking");
+        this.main.append(mk('p', {}, message));
+        let yes = mk('button', {type: 'button'}, "yep");
+        let no = mk('button', {type: 'button'}, "nope");
+        yes.addEventListener('click', ev => {
+            this.close();
+            what();
+        });
+        no.addEventListener('click', ev => {
+            this.close();
+        });
+        this.footer.append(yes, no);
+    }
+}
+
+export function load_json_from_storage(key) {
+    return JSON.parse(window.localStorage.getItem(key));
+}
+
+export function save_json_to_storage(key, value) {
+    window.localStorage.setItem(key, JSON.stringify(value));
+}
@@ -1,4 +1,4 @@
-import { DIRECTIONS } from './defs.js';
+import { DIRECTIONS, DRAW_LAYERS } from './defs.js';
 import { mk } from './util.js';
 import TILE_TYPES from './tiletypes.js';

@@ -11,7 +11,6 @@ export class CanvasRenderer {
        // to do so, but then we wouldn't make a canvas so it couldn't be
        // hooked, yadda yadda
        if (fixed_size) {
-            this.viewport_is_fixed = true;
            this.viewport_size_x = fixed_size;
            this.viewport_size_y = fixed_size;
        }
@@ -25,7 +24,10 @@ export class CanvasRenderer {
        this.ctx = this.canvas.getContext('2d');
        this.viewport_x = 0;
        this.viewport_y = 0;
+        this.viewport_dirty = false;
+        this.show_actor_bboxes = false;
        this.use_rewind_effect = false;
+        this.perception = 0;  // 0 normal, 1 secret eye, 2 editor
    }

    set_level(level) {
@@ -33,6 +35,13 @@ export class CanvasRenderer {
        // TODO update viewport size...  or maybe Game should do that since you might be cheating
    }

+    // Change the viewport size.  DOES NOT take effect until the next redraw!
+    set_viewport_size(x, y) {
+        this.viewport_size_x = x;
+        this.viewport_size_y = y;
+        this.viewport_dirty = true;
+    }
+
    cell_coords_from_event(ev) {
        let rect = this.canvas.getBoundingClientRect();
        let scale_x = rect.width / this.canvas.width;
@@ -42,6 +51,15 @@ export class CanvasRenderer {
        return [x, y];
    }

+    real_cell_coords_from_event(ev) {
+        let rect = this.canvas.getBoundingClientRect();
+        let scale_x = rect.width / this.canvas.width;
+        let scale_y = rect.height / this.canvas.height;
+        let x = (ev.clientX - rect.x) / scale_x / this.tileset.size_x + this.viewport_x;
+        let y = (ev.clientY - rect.y) / scale_y / this.tileset.size_y + this.viewport_y;
+        return [x, y];
+    }
+
    // Draw to a canvas using tile coordinates
    blit(ctx, sx, sy, dx, dy, w = 1, h = w) {
        let tw = this.tileset.size_x;
@@ -58,6 +76,14 @@ export class CanvasRenderer {
            return;
        }

+        if (this.viewport_dirty) {
+            this.viewport_dirty = false;
+            this.canvas.setAttribute('width', this.tileset.size_x * this.viewport_size_x);
+            this.canvas.setAttribute('height', this.tileset.size_y * this.viewport_size_y);
+            this.canvas.style.setProperty('--viewport-width', this.viewport_size_x);
+            this.canvas.style.setProperty('--viewport-height', this.viewport_size_y);
+        }
+
        let tic = (this.level.tic_counter ?? 0) + tic_offset;
        let tw = this.tileset.size_x;
        let th = this.tileset.size_y;
@@ -76,8 +102,24 @@ export class CanvasRenderer {
            [px, py] = [0, 0];
        }
        // Figure out where to start drawing
-        let x0 = Math.max(0, Math.min(this.level.size_x - this.viewport_size_x, px - xmargin));
-        let y0 = Math.max(0, Math.min(this.level.size_y - this.viewport_size_y, py - ymargin));
+        // TODO support overlapping regions better
+        let x0 = px - xmargin;
+        let y0 = py - ymargin;
+        // FIXME editor vs player again ugh, which is goofy since none of this is even relevant;
+        // maybe need to have a separate positioning method
+        if (this.level.stored_level) {
+        for (let region of this.level.stored_level.camera_regions) {
+            if (px >= region.left && px < region.right &&
+                py >= region.top && py < region.bottom)
+            {
+                x0 = Math.max(region.left, Math.min(region.right - this.viewport_size_x, x0));
+                y0 = Math.max(region.top, Math.min(region.bottom - this.viewport_size_y, y0));
+            }
+        }
+        }
+        // Always keep us within the map bounds
+        x0 = Math.max(0, Math.min(this.level.size_x - this.viewport_size_x, x0));
+        y0 = Math.max(0, Math.min(this.level.size_y - this.viewport_size_y, y0));
        // Round to the pixel grid
        x0 = Math.floor(x0 * tw + 0.5) / tw;
        y0 = Math.floor(y0 * th + 0.5) / th;
@@ -86,12 +128,12 @@ export class CanvasRenderer {
        // The viewport might not be aligned to the grid, so split off any fractional part.
        let xf0 = Math.floor(x0);
        let yf0 = Math.floor(y0);
-        // Note that when the viewport is exactly aligned to the grid, we need to draw the cells
-        // just outside of it, or we'll miss objects partway through crossing the border
-        if (xf0 === x0 && xf0 > 0) {
+        // We need to draw one cell beyond the viewport, or we'll miss objects partway through
+        // crossing the border moving away from us
+        if (xf0 > 0) {
            xf0 -= 1;
        }
-        if (yf0 === y0 && yf0 > 0) {
+        if (yf0 > 0) {
            yf0 -= 1;
        }
        // Find where to stop drawing.  As with above, if we're aligned to the grid, we need to
@@ -100,36 +142,63 @@ export class CanvasRenderer {
        let y1 = Math.min(this.level.size_y - 1, Math.ceil(y0 + this.viewport_size_y));
        // Draw one layer at a time, so animated objects aren't overdrawn by
        // neighboring terrain
-        // XXX layer count hardcoded here
-        for (let layer = 0; layer < 4; layer++) {
+        // FIXME this is a bit inefficient when there are a lot of rarely-used layers; consider
+        // instead drawing everything under actors, then actors, then everything above actors?
+        for (let layer = 0; layer < DRAW_LAYERS.MAX; layer++) {
            for (let x = xf0; x <= x1; x++) {
                for (let y = yf0; y <= y1; y++) {
                    for (let tile of this.level.cells[y][x]) {
                        if (tile.type.draw_layer !== layer)
                            continue;

+                        let vx, vy;
                        if (tile.type.is_actor &&
                            // FIXME kind of a hack for the editor, which uses bare tile objects
                            tile.visual_position)
                        {
                            // Handle smooth scrolling
-                            let [vx, vy] = tile.visual_position(tic_offset);
+                            [vx, vy] = tile.visual_position(tic_offset);
                            // Round this to the pixel grid too!
                            vx = Math.floor(vx * tw + 0.5) / tw;
                            vy = Math.floor(vy * th + 0.5) / th;
-                            this.tileset.draw(tile, tic, (sx, sy, dx = 0, dy = 0, w = 1, h = w) =>
-                                this.blit(this.ctx, sx, sy, vx - x0 + dx, vy - y0 + dy, w, h));
                        }
                        else {
                            // Non-actors can't move
-                            this.tileset.draw(tile, tic, (sx, sy, dx = 0, dy = 0, w = 1, h = w) =>
-                                this.blit(this.ctx, sx, sy, x - x0 + dx, y - y0 + dy, w, h));
+                            vx = x;
+                            vy = y;
                        }
+
+                        // Note that the blit we pass to the tileset has a different signature:
+                        // blit(
+                        //     source_tile_x, source_tile_y,
+                        //     mask_x = 0, mask_y = 0, mask_width = 1, mask_height = mask_width,
+                        //     mask_dx = mask_x, mask_dy = mask_y)
+                        // This makes it easier to use in the extremely common case of drawing
+                        // part of one tile atop another tile, but still aligned to the grid.
+                        this.tileset.draw(tile, tic, (tx, ty, mx = 0, my = 0, mw = 1, mh = mw, mdx = mx, mdy = my) =>
+                            this.blit(this.ctx,
+                                tx + mx, ty + my,
+                                vx - x0 + mdx, vy - y0 + mdy,
+                                mw, mh));
                    }
                }
            }
        }

+        if (this.show_actor_bboxes && ! this.level.linear_cells) {  // FIXME dumb hack so this doesn't happen in editor
+            this.ctx.fillStyle = '#f004';
+            for (let x = xf0; x <= x1; x++) {
+                for (let y = yf0; y <= y1; y++) {
+                    let actor = this.level.cells[y][x].get_actor();
+                    if (! actor)
+                        continue;
+                    let [vx, vy] = actor.visual_position(tic_offset);
+                    // Don't round to the pixel grid; we want to know if the bbox is misaligned!
+                    this.ctx.fillRect((vx - x0) * tw, (vy - y0) * th, 1 * tw, 1 * th);
+                }
+            }
+        }
+
        if (this.use_rewind_effect) {
            this.draw_rewind_effect(tic);
        }
@@ -149,11 +218,11 @@ export class CanvasRenderer {
        }
    }

-    create_tile_type_canvas(name) {
+    create_tile_type_canvas(name, tile = null) {
        let canvas = mk('canvas', {width: this.tileset.size_x, height: this.tileset.size_y});
        let ctx = canvas.getContext('2d');
-        this.tileset.draw_type(name, null, 0, (sx, sy, dx = 0, dy = 0, w = 1, h = w) =>
-            this.blit(ctx, sx, sy, dx, dy, w, h));
+        this.tileset.draw_type(name, tile, 0, this.perception, (tx, ty, mx = 0, my = 0, mw = 1, mh = mw, mdx = mx, mdy = my) =>
+            this.blit(ctx, tx + mx, ty + my, mdx, mdy, mw, mh));
        return canvas;
    }
 }
@@ -43,7 +43,7 @@ export default [{
    title: "conundrum",
    author: "fluffy",
    url: 'https://beesbuzz.biz/',
-    beepbox: 'https://www.beepbox.co/#8n31sbk0l00e0rt2mm0a7g0rj07i0r1o3210T1v1L4u01q3d7fay3z6C0c1A5F4B0V1Q0248Pac74E0085T1v1L4u01q1d1f4y4z9C0c1A1F0B0V1Q200ePd593E0787T5v1L4u05q3d0f1y4z0C2c0h0H_--D-quSRIAJJST4v1L4u04q1z6666ji8k8k3jSBKSJJAArriiiiii07JCABrzrrrrrrr00YrkqHrsrrrrjr005zrAqzrjzrrqr1jRjrqGGrrzsrsA099ijrABJJJIAzrrtirqrqjqixzsrAjrqjiqaqqysttAJqjikikrizrHtBJJAzArzrIsRCITKSS099ijrAJS____Qg99habbCAYrDzh00bkzgid18Q4zgid0000000018Nwz55p88Nhnh5t000000ichgR5zkicg004hcx4O4jhkohd14z4isp25PFJvy1wqY58llp2GhKFLh_wFLh-czArdWfRuKrdQ_p13c5FKfZ_tRBPjub_aq_TYtjhZgtBdJlldtlldtlleKGGCKGGCK1wqoiGGiOdI3j1RlkOJBtdZllmG1wqoiGGCK1JFxaEm1STTQMBlldtlldtlJKoHrarqGGqWGGqWGGth7ihT4sChON7a4sIpqPhDkCz9FFOG8YwzOF8Wp8WFOHyfAVARQVB4ughVkAtcAtkVl97Op8Wd8Td6nl9EOaqSqcyIz9UzMbaXbAenShhAPvehhrBRApcVmnlsV5vaGysD9CKsyyLbH8OpOIKGVEGKttV56jdkV55uTnpeldpuptSltdRKpEPpFFOW8YwzOF8Wp8WFOGU0',
+    beepbox: 'https://www.beepbox.co/#8n31sbk0l00e0rt2mm0a7g0rj07i0r1o3210T1v1L4u01q3d7fay3z6C0c1A5F4B0V1Q0248Pac74E0085T1v1L4u01q1d1f4y4z9C0c1A1F0B0V1Q200ePd593E0787T5v1L4u05q3d0f1y4z0C2c0h0H_--D-quSRIAJJST4v1L4u04q1z6666ji8k8k3jSBKSJJAArriiiiii07JCABrzrrrrrrr00YrkqHrsrrrrjr005zrAqzrjzrrqr1jRjrqGGrrzsrsA099ijrABJJJIAzrrtirqrqjqixzsrAjrqjiqaqqysttAJqjikikrizrHtBJJAzArzrIsRCITKSS099ijrAJS____Qg99habbCAYrDzh00b4zgid18Q4zgid0000000018Nwz55p88Nhnh5t000000ichgR5zkicg004hcx4O4jhkohd14z4isp25PFJvy1wqY58llp2GhKFLh_wFLh-czArdWfRuKrdQ_p13c5FKfZ_tRBPjub_aq_TYtjhZgtBdJlldtlldtlleKGGCKGGCK1wqoiGGiOdI3j1RlkOJBtdZllmG1wqoiGGCK1JFxaEm1STTQMBlldtlldtlJKoHrarqGGqWGGqWGGth7ihT4sChON7a4sIpqPhDkCz9FFOG8YwzOF8Wp8WFOHyfAVARQVB4ughVkAtcAtkVl97Op8Wd8Td6nl9EOaqSqcyIz9UzMbaXbAenShhAPvehhrBRApcVmnlsV5vaGysD9CKsyyLbH8OpOIKGVEGKttV56jdkV55uTnpeldpuptSltdRKpEPpFFOW8YwzOF8Wp8WFOGU0',
    path: 'music/conundrum.ogg',
 }, {
    title: "kinda song",
@@ -51,4 +51,29 @@ export default [{
    twitter: "glitchedpuppet",
    beepbox: 'https://jummbus.bitbucket.io/#j2N07Unnamedn310s0k0l00e0jt2mm0a7g0jj07i0r1O_U0000o3210T1v0wL0OD0Ou01q1d5f6y0z6C1c0A1F2B5V6Q20a0Pe64bE0171T1v0pL0OD0Ou92q1d4f7y2z1C0c2AbF6B6V9Q0490Pb976E0001T1v0pL0OD0Ou94q1d2f7y2z1C0c2A9F5B5V6Q290dPa883E0011T4v0pL0OD0Ouf0q1z6666ji8k8k3jSBKSJJAArriiiiii07JCABrzrrrrrrr00YrkqHrsrrrrjr005zrAqzrjzrrqr1jRjrqGGrrzsrsA099ijrABJJJIAzrrtirqrqjqixzsrAjrqjiqaqqysttAJqjikikrizrHtBJJAzArzrIsRCITKSS099ijrAJS____Qg99habbCAYrDzh00b4x8Qd000lBu7014x4i4Qd3gQlmoh4ia2cz8OcChA4h4y8w01cPhjl0p27hFCLwATnMkCKChW2ZcngbUxcnikQ7sQO_inQ5WCkXyW9jbZ9vlO_lODhdcDjQNtgJ0Gp7IpAukFczR2FyX2frIzQ4zOGOOfpauP9vainRihQPK4tClqoKMnaAzQQnQQnRknXx7pBnK2OFjSO_oELFAzFIOWa8WF8WpHW3nEdv26LgqZcLQQap7Iu6P9j5R2Q2Q2Q2VeRfbEbWGq2-DinQBZttkHUMRWPn9HFAuwzEe3E8W2ehFyUsNncLQThuCnW2_aGydcngbkO_rZdkPjdcSpvx9jbZ3cRZtcO_lipvFSFkO_lN4YlAjBpdp6hahFyWz5OXbWFbWF8YEmChy3wWiehcK0bWaoEIlChw3JHp5K5E5E5w1sPb5P2f9as0LVds0bkbukQni0JFyQ5c0bokRyXrbxqxr2CyWSOSAzw1qxqxrNrxqxrhtwJgJMJJhvmbibikO8J5JwJEJEJtE',
    path: 'music/kinda-song.ogg',
+}, {
+    title: "learning has occurred",
+    author: "jneen",
+    twitter: "jneen_",
+    path: 'music/learning-has-occurred.ogg',
+}, {
+    title: "escape on star road",
+    author: "jneen",
+    twitter: "jneen_",
+    path: 'music/escape-on-star-road.ogg',
+}, {
+    title: "inner orbit",
+    author: "notchris",
+    twitter: "chrismcgrane",
+    path: 'music/inner-orbit.ogg',
+}, {
+    title: "canopy",
+    author: "notchris",
+    twitter: "chrismcgrane",
+    path: 'music/canopy.ogg',
+}, {
+    title: "asteroid prairie",
+    author: "notchris",
+    twitter: "chrismcgrane",
+    path: 'music/asteroid-prairie.ogg',
 }];
@@ -3,14 +3,36 @@ import TILE_TYPES from './tiletypes.js';

 // TODO really need to specify this format more concretely, whoof
 // XXX special kinds of drawing i know this has for a fact:
-// - letter tiles draw from a block of half-tiles onto the center of the base
-// - slime and walkers have double-size tiles when moving
-// - wired tiles are a whole thing
+// - letter tiles draw from a block (one of two blocks!) of half-tiles onto the center of the base
+// - force floors are cropped from a double-size tile
+// - wired tiles are a whole thing (floor)
 // - thin walls are packed into just two tiles
-// - rover has a half-tile overlay for its direction?
-// - railroad tracks overlay a Lot
 // - directional blocks have arrows in an awkward layout, not 4x4 grid but actually positioned on the edges
 // - green and purple toggle walls use an overlay
+// - turtles use an overlay, seem to pick a tile at random every so often
+// - animations are common, should maybe have configurable timing??
+// - custom floors and walls /should/ be consolidated into a single tile probably
+// - thin walls should probably be consolidated?
+// - traps have a state
+
+// special features i currently have
+// - directions for actors, can be used anywhere
+// - arrows: for directional blocks
+// - mask: for thin walls (though the idea is useful in many more places)
+// - wired: for wired tiles
+// - overlay: for green/purple walls mostly, also some bogus cc1 tiles
+
+// things that are currently NOT handled
+// - bomb is supposed to have a fuse
+// - critters should only animate when moving
+// - rover animation depends on behavior, also has a quarter-tile overlay for its direction
+// - slime and walkers have double-size tiles when moving
+// - logic gates draw over the stuff underneath them
+// - railroad tracks overlay a Lot
+// - canopy, at all
+// - swivel's floor (eugh)
+// - xray vision
+// - editor vision
 export const CC2_TILESET_LAYOUT = {
    '#wire-width': 1/16,

@@ -22,8 +44,13 @@ export const CC2_TILESET_LAYOUT = {
    key_blue: [5, 1],
    key_yellow: [6, 1],
    key_green: [7, 1],
-    dirt_block: [8, 1],
-    // xray
+    // FIXME these shouldn't be drawn with a hole when drawn in isolation, gruh
+    dirt_block: {
+        special: 'perception',
+        threshold: 2,
+        hidden: [8, 1],
+        revealed: [9, 1],
+    },
    ice: [10, 1],
    ice_se: [11, 1],
    ice_sw: [12, 1],
@@ -35,23 +62,44 @@ export const CC2_TILESET_LAYOUT = {
        // Wiring!
        base: [0, 2],
        wired: [8, 26],
+        wired_cross: [10, 26],
        is_wired_optional: true,
    },
-    wall_invisible: [0, 2],
-    wall_appearing: [0, 2],
-    wall: [1, 2],
-    floor_letter: [2, 2],
-    'floor_letter#ascii': {
-        x0: 0,
-        y0: 0,
-        width: 16,
-        height: 1,
+    // FIXME i think these are visible with the secret eye, but my tileset puts text on them, whoops
+    wall_invisible: {
+        special: 'perception',
+        threshold: 2,
+        hidden: [0, 2],
+        revealed: [9, 31],
    },
-    'floor_letter#arrows': {
-        north: [14, 31],
-        east: [14.5, 31],
-        south: [15, 31],
-        west: [15.5, 31],
+    // FIXME this shouldn't be visible with seeing eye (or should it not spawn at all?)
+    wall_invisible_revealed: [1, 2],
+    wall_appearing: {
+        special: 'perception',
+        threshold: 2,
+        hidden: [0, 2],
+        revealed: [11, 31],
+    },
+    wall: [1, 2],
+    floor_letter: {
+        special: 'letter',
+        base: [2, 2],
+        letter_glyphs: {
+            // Arrows
+            "⬆": [14, 31],
+            "➡": [14.5, 31],
+            "⬇": [15, 31],
+            "⬅": [15.5, 31],
+        },
+        letter_ranges: [{
+            // ASCII text (only up through uppercase)
+            range: [32, 96],
+            x0: 0,
+            y0: 0,
+            w: 0.5,
+            h: 0.5,
+            columns: 32,
+        }],
    },
    thief_tools: [3, 2],
    socket: [4, 2],
@@ -62,8 +110,13 @@ export const CC2_TILESET_LAYOUT = {
        [8, 2],
        [9, 2],
    ],
-    ice_block: [10, 2],
-    // TODO ice block xray
+    // FIXME these shouldn't be drawn with a hole when drawn in isolation, gruh
+    ice_block: {
+        special: 'perception',
+        threshold: 2,
+        hidden: [10, 2],
+        revealed: [11, 2],
+    },
    score_1000: [12, 2],
    score_100: [13, 2],
    score_10: [14, 2],
@@ -73,9 +126,10 @@ export const CC2_TILESET_LAYOUT = {
    green_chip: [9, 3],
    chip_extra: [10, 3],
    chip: [11, 3],
-    // bribe
-    // mercury boot
-    // canopy, xray
+    bribe: [12, 3],
+    speed_boots: [13, 3],
+    canopy: [14, 3],
+    // canopy xray

    // TODO lit
    dynamite: [0, 4],
@@ -92,24 +146,40 @@ export const CC2_TILESET_LAYOUT = {
    wall_custom_blue: [15, 4],

    explosion: [[0, 5], [1, 5], [2, 5], [3, 5]],
+    splash_slime: [[0, 5], [1, 5], [2, 5], [3, 5]],
    splash: [[4, 5], [5, 5], [6, 5], [7, 5]],
    flame_jet_off: [8, 5],
    flame_jet_on: [[9, 5], [10, 5], [11, 5]],
    popdown_wall: [12, 5],
-    popdown_floor: [12, 5],
+    popdown_floor: {
+        special: 'perception',
+        threshold: 2,
+        hidden: [12, 5],
+        revealed: [13, 5],
+    },
    popdown_floor_visible: [13, 5],
-    forbidden: [14, 5],
-    // TODO arrows overlay at [3, 10]
-    directional_block: [15, 5],
+    no_sign: [14, 5],
+    frame_block: {
+        base: [15, 5],
+        arrows: [3, 10],
+    },

    flippers: [0, 6],
    fire_boots: [1, 6],
    cleats: [2, 6],
    suction_boots: [3, 6],
    hiking_boots: [4, 6],
-    // speed boots...?  not boots though
+    lightning_bolt: [5, 6],
    // weird translucent spiral
-    // weird translucent red
+    // TODO dopps can push but i don't think they have any other visuals
+    doppelganger1: {
+        base: [7, 6],
+        overlay: 'player',
+    },
+    doppelganger2: {
+        base: [7, 6],
+        overlay: 'player2',
+    },
    button_blue: [8, 6],
    button_green: [9, 6],
    button_red: [10, 6],
@@ -168,7 +238,13 @@ export const CC2_TILESET_LAYOUT = {
    ],

    fake_wall: [0, 10],
-    fake_floor: [0, 10],
+    // FIXME i think these are visible with the secret eye, but my tileset puts text on them, whoops
+    fake_floor: {
+        special: 'perception',
+        threshold: 2,
+        hidden: [0, 10],
+        revealed: [10, 31],
+    },
    // Thin walls are built piecemeal from these two tiles; the first is N/S,
    // the second is E/W
    thinwall_n: {
@@ -197,25 +273,42 @@ export const CC2_TILESET_LAYOUT = {
        wired: [[4, 10], [5, 10], [6, 10], [7, 10]],
    },
    popwall: [8, 10],
+    popwall2: [8, 10],
    gravel: [9, 10],
-    ball: [[10, 10], [11, 10], [12, 10], [13, 10], [14, 10]],
-    steel: [15, 10],
+    ball: [
+        // appropriately, this animation ping-pongs
+        [10, 10], [11, 10], [12, 10], [13, 10],
+        [14, 10], [13, 10], [12, 10], [11, 10],
+        // FIXME the ball bounces so it specifically needs to play its animation every move; this
+        // defeats the ½x slowdown.  it's dumb and means this anim as written doesn't match cc2
+        [10, 10], [11, 10], [12, 10], [13, 10],
+        [14, 10], [13, 10], [12, 10], [11, 10],
+    ],
+    steel: {
+        // Wiring!
+        base: [15, 10],
+        wired: [9, 26],
+        wired_cross: [11, 26],
+        is_wired_optional: true,
+    },

-    // TODO only animates while moving
+    // TODO should explicitly set the non-moving tile, so we can have the walk tile start with
+    // immediate movement?
+    // TODO this shouldn't run at half speed, it's already designed to be one step, and when teeth
+    // move at half speed it looks clumsy
    teeth: {
-        // NOTE: CC2 inexplicably dropped north teeth and just uses the south
-        // sprites instead
-        north: [[0, 11], [1, 11], [2, 11]],
-        east: [[3, 11], [4, 11], [5, 11]],
-        south: [[0, 11], [1, 11], [2, 11]],
-        west: [[6, 11], [7, 11], [8, 11]],
+        // NOTE: CC2 inexplicably dropped north teeth and just uses the south sprites instead
+        north: [[1, 11], [0, 11], [1, 11], [2, 11]],
+        east: [[4, 11], [3, 11], [4, 11], [5, 11]],
+        south: [[1, 11], [0, 11], [1, 11], [2, 11]],
+        west: [[7, 11], [6, 11], [7, 11], [8, 11]],
    },
    swivel_sw: [9, 11],
    swivel_nw: [10, 11],
    swivel_ne: [11, 11],
    swivel_se: [12, 11],
    swivel_floor: [13, 11],
-    // TODO some kinda four-edges thing again
+    '#wire-tunnel': [14, 11],
    stopwatch_penalty: [15, 11],
    paramecium: {
        north: [[0, 12], [1, 12], [2, 12]],
@@ -231,18 +324,31 @@ export const CC2_TILESET_LAYOUT = {
    },

    walker: [0, 13],
-    // TODO walker animations span multiple tiles, rgh
+    // FIXME walker animations span multiple tiles
    helmet: [0, 14],
    stopwatch_toggle: [14, 14],
    stopwatch_bonus: [15, 14],

    blob: [0, 15],
-    // TODO blob animations also span multiple tiles
+    // FIXME blob animations span multiple tiles
    // TODO [0, 16] some kinda red/blue outline
-    floor_mimic: [0, 2],  // TODO [14, 16] with xray
+    floor_mimic: {
+        special: 'perception',
+        threshold: 1,
+        hidden: [0, 2],
+        revealed: [14, 16],
+    },
    // TODO [15, 16] some kinda yellow/black outline

    // timid teeth
+    teeth_timid: {
+        // NOTE: CC2 inexplicably dropped north teeth and just uses the south sprites instead
+        // NOTE: it also skimped on timid teeth frames
+        north: [[1, 17], [0, 17]],
+        east: [[3, 17], [2, 17]],
+        south: [[1, 17], [0, 17]],
+        west: [[5, 17], [4, 17]],
+    },
    bowling_ball: [6, 17],  // TODO also +18 when rolling
    tank_yellow: {
        north: [[8, 17], [9, 17]],
@@ -251,8 +357,26 @@ export const CC2_TILESET_LAYOUT = {
        west: [[14, 17], [15, 17]],
    },

-    // TODO rover has layers and moves and stuff
-    rover: [0, 18],
+    // TODO rover has an overlay showing its direction
+    rover: {
+        inert: [0, 18],
+        teeth: [[0, 18], [8, 18]],
+        glider: [
+            // quite fast
+            [0, 18], [1, 18], [2, 18], [3, 18], [4, 18], [5, 18], [6, 18], [7, 18],
+            [0, 18], [1, 18], [2, 18], [3, 18], [4, 18], [5, 18], [6, 18], [7, 18],
+        ],
+        bug: [[0, 18], [1, 18], [2, 18], [3, 18], [4, 18], [5, 18], [6, 18], [7, 18]],
+        ball: [[0, 18], [4, 18]],
+        teeth_timid: [[0, 18], [9, 18]],
+        fireball: [
+            // quite fast
+            [7, 18], [6, 18], [5, 18], [4, 18], [3, 18], [2, 18], [1, 18], [0, 18],
+            [7, 18], [6, 18], [5, 18], [4, 18], [3, 18], [2, 18], [1, 18], [0, 18],
+        ],
+        paramecium: [[7, 18], [6, 18], [5, 18], [4, 18], [3, 18], [2, 18], [1, 18], [0, 18]],
+        walker: [[8, 18], [9, 18]],
+    },
    xray_eye: [11, 18],
    ghost: {
        north: [12, 18],
@@ -288,7 +412,14 @@ export const CC2_TILESET_LAYOUT = {

    force_floor_all: [[0, 21], [1, 21], [2, 21], [3, 21], [4, 21], [5, 21], [6, 21], [7, 21]],
    // latches
-    // switch
+    light_switch_off: {
+        base: [14, 21],
+        wired: [12, 21],
+    },
+    light_switch_on: {
+        base: [14, 21],
+        wired: [13, 21],
+    },
    thief_keys: [15, 21],

    player: {
@@ -326,8 +457,10 @@ export const CC2_TILESET_LAYOUT = {
            south: [2, 23],
            west: [10, 23],
        },
+        exited: 'normal',
        // These are frames from the splash/explosion animations
        drowned: [5, 5],
+        slimed: [5, 5],
        burned: [1, 5],
        exploded: [1, 5],
        failed: [1, 5],
@@ -343,7 +476,7 @@ export const CC2_TILESET_LAYOUT = {
        west: [[6, 24], [7, 24]],
    },
    bogus_player_drowned: {
-        overlay: [3, 3],  // splash
+        overlay: [5, 5],  // splash
        base: 'water',
    },
    bogus_player_burned_fire: {
@@ -361,22 +494,100 @@ export const CC2_TILESET_LAYOUT = {
        [15, 24],
    ],

+    logic_gate: {
+        special: 'logic-gate',
+        logic_gate_tiles: {
+            'latch-ccw': {
+                north: [8, 21],
+                east: [9, 21],
+                south: [10, 21],
+                west: [11, 21],
+            },
+            not: {
+                north: [0, 25],
+                east: [1, 25],
+                south: [2, 25],
+                west: [3, 25],
+            },
+            and: {
+                north: [4, 25],
+                east: [5, 25],
+                south: [6, 25],
+                west: [7, 25],
+            },
+            or: {
+                north: [8, 25],
+                east: [9, 25],
+                south: [10, 25],
+                west: [11, 25],
+            },
+            xor: {
+                north: [12, 25],
+                east: [13, 25],
+                south: [14, 25],
+                west: [15, 25],
+            },
+            'latch-cw': {
+                north: [0, 26],
+                east: [1, 26],
+                south: [2, 26],
+                west: [3, 26],
+            },
+            nand: {
+                north: [4, 26],
+                east: [5, 26],
+                south: [6, 26],
+                west: [7, 26],
+            },
+            counter: [14, 26],
+        },
+    },
+
    '#unpowered': [13, 26],
    '#powered': [15, 26],

    player2: {
-        moving: {
-            north: [[0, 27], [1, 27], [2, 27], [3, 27], [4, 27], [5, 27], [6, 27], [7, 27]],
-            south: [[0, 28], [1, 28], [2, 28], [3, 28], [4, 28], [5, 28], [6, 28], [7, 28]],
-            west: [[8, 28], [9, 28], [10, 28], [11, 28], [12, 28], [13, 28], [14, 28], [15, 28]],
-            east: [[8, 27], [9, 27], [10, 27], [11, 27], [12, 27], [13, 27], [14, 27], [15, 27]],
-        },
        normal: {
            north: [0, 27],
            south: [0, 28],
            west: [8, 28],
            east: [8, 27],
        },
+        blocked: 'pushing',
+        moving: {
+            north: [[0, 27], [1, 27], [2, 27], [3, 27], [4, 27], [5, 27], [6, 27], [7, 27]],
+            south: [[0, 28], [1, 28], [2, 28], [3, 28], [4, 28], [5, 28], [6, 28], [7, 28]],
+            west: [[8, 28], [9, 28], [10, 28], [11, 28], [12, 28], [13, 28], [14, 28], [15, 28]],
+            east: [[8, 27], [9, 27], [10, 27], [11, 27], [12, 27], [13, 27], [14, 27], [15, 27]],
+        },
+        pushing: {
+            north: [8, 29],
+            east: [9, 29],
+            south: [10, 29],
+            west: [11, 29],
+        },
+        swimming: {
+            north: [[0, 29], [1, 29]],
+            east: [[2, 29], [3, 29]],
+            south: [[4, 29], [5, 29]],
+            west: [[6, 29], [7, 29]],
+        },
+        // The classic CC2 behavior, spinning on ice
+        skating: [[0, 27], [8, 27], [0, 28], [8, 28]],
+        // TODO i don't know what CC2 does
+        forced: {
+            north: [2, 27],
+            east: [10, 27],
+            south: [2, 28],
+            west: [10, 28],
+        },
+        exited: 'normal',
+        // These are frames from the splash/explosion animations
+        drowned: [5, 5],
+        slimed: [5, 5],
+        burned: [1, 5],
+        exploded: [1, 5],
+        failed: [1, 5],
    },
    fire: [
        [12, 29],
@@ -386,11 +597,40 @@ export const CC2_TILESET_LAYOUT = {
    ],

    // TODO handle train tracks!  this is gonna be complicated.
-    railroad: [9, 10],
-    railroad_sign: [4, 31],
+    railroad: {
+        special: 'railroad',
+        base: [9, 10],
+        railroad_ties: {
+            ne: [0, 30],
+            se: [1, 30],
+            sw: [2, 30],
+            nw: [3, 30],
+            ew: [4, 30],
+            ns: [5, 30],
+        },
+        railroad_switch: [6, 30],
+        railroad_inactive: {
+            ne: [7, 30],
+            se: [8, 30],
+            sw: [9, 30],
+            nw: [10, 30],
+            ew: [11, 30],
+            ns: [12, 30],
+        },
+        railroad_active: {
+            ne: [13, 30],
+            se: [14, 30],
+            sw: [15, 30],
+            nw: [0, 31],
+            ew: [1, 31],
+            ns: [2, 31],
+        },
+    },
+    railroad_sign: [3, 31],
    dirt: [4, 31],
    no_player2_sign: [5, 31],
    no_player1_sign: [6, 31],
+    hook: [7, 31],
    // misc other stuff
 };

@@ -402,6 +642,7 @@ export const TILE_WORLD_TILESET_LAYOUT = {
    water: [0, 3],
    fire: [0, 4],
    wall_invisible: [0, 5],
+    wall_invisible_revealed: [0, 1],
    thinwall_n: [0, 6],
    thinwall_w: [0, 7],
    thinwall_s: [0, 8],
@@ -451,6 +692,7 @@ export const TILE_WORLD_TILESET_LAYOUT = {
    wall_appearing: [2, 12],
    gravel: [2, 13],
    popwall: [2, 14],
+    popwall2: [2, 14],
    hint: [2, 15],

    thinwall_se: [3, 0],
@@ -562,8 +804,14 @@ export const TILE_WORLD_TILESET_LAYOUT = {
 export const LL_TILESET_LAYOUT = Object.assign({}, CC2_TILESET_LAYOUT, {
    // Completed teeth sprites
    teeth: Object.assign({}, CC2_TILESET_LAYOUT.teeth, {
-        north: [[0, 32], [1, 32], [2, 32], [1, 32]],
+        north: [[1, 32], [0, 32], [1, 32], [2, 32]],
    }),
+    teeth_timid: {
+        north: [[7, 32], [6, 32], [7, 32], [8, 32]],
+        east:  [[4, 32], [2, 17], [4, 32], [3, 17]],
+        south: [[3, 32], [0, 17], [3, 32], [1, 17]],
+        west:  [[5, 32], [4, 17], [5, 32], [5, 17]],
+    },

    // Extra player sprites
    player: Object.assign({}, CC2_TILESET_LAYOUT.player, {
@@ -574,12 +822,25 @@ export const LL_TILESET_LAYOUT = Object.assign({}, CC2_TILESET_LAYOUT, {
            west: [3, 33],
        },
        forced: 'skating',
+        exited: [14, 32],
        burned: {
            north: [4, 33],
            east: [5, 33],
            south: [6, 33],
            west: [7, 33],
        },
+        slimed: [1, 38],
+    }),
+    player2: Object.assign({}, CC2_TILESET_LAYOUT.player2, {
+        // TODO skating
+        exited: [15, 32],
+        burned: {
+            north: [12, 33],
+            east: [13, 33],
+            south: [14, 33],
+            west: [15, 33],
+        },
+        slimed: [1, 38],
    }),
    bogus_player_burned_fire: {
        overlay: [6, 33],
@@ -589,6 +850,33 @@ export const LL_TILESET_LAYOUT = Object.assign({}, CC2_TILESET_LAYOUT, {
        overlay: [6, 33],
        base: 'floor',
    },
+
+    // Custom tiles
+    popwall2: [9, 32],
+    gift_bow: [10, 32],
+    circuit_block: {
+        base: [13, 32],
+        wired: [11, 32],
+        wired_cross: [12, 32],
+    },
+
+    // Blob and walker in all four directions
+    blob: {
+        north: [[0, 35], [1, 35], [2, 35], [3, 35], [4, 35], [5, 35], [6, 35], [7, 35]],
+        east: [[8, 35], [9, 35], [10, 35], [11, 35], [12, 35], [13, 35], [14, 35], [15, 35]],
+        south: [[0, 36], [1, 36], [2, 36], [3, 36], [4, 36], [5, 36], [6, 36], [7, 36]],
+        west: [[8, 36], [9, 36], [10, 36], [11, 36], [12, 36], [13, 36], [14, 36], [15, 36]],
+    },
+    walker: {
+        north: [[0, 37], [1, 37], [2, 37], [3, 37]],
+        east: [[4, 37], [5, 37], [6, 37], [7, 37]],
+        // Same animations but played backwards
+        south: [[2, 37], [1, 37], [0, 37], [3, 37]],
+        west: [[6, 37], [5, 37], [4, 37], [7, 37]],
+    },
+
+    // Custom VFX
+    splash_slime: [[0, 38], [1, 38], [2, 38], [3, 38]],
 });

 export class Tileset {
@@ -601,12 +889,163 @@ export class Tileset {
    }

    draw(tile, tic, blit) {
-        this.draw_type(tile.type.name, tile, tic, blit);
+        // FIXME perception
+        this.draw_type(tile.type.name, tile, tic, 0, blit);
+    }
+
+    // Draw a "standard" drawspec, which is either:
+    // - a single tile: [x, y]
+    // - an animation: [[x0, y0], [x1, y1], ...]
+    // - a directional tile: { north: T, east: T, ... } where T is either of the above
+    _draw_standard(drawspec, tile, tic, blit, mask = []) {
+        // If we have an object, it must be a table of directions
+        let coords = drawspec;
+        if (!(coords instanceof Array)) {
+            coords = coords[(tile && tile.direction) ?? 'south'];
+        }
+
+        // Deal with animation
+        if (coords[0] instanceof Array) {
+            if (tic !== null) {
+                if (tile && tile.animation_speed) {
+                    // This tile reports its own animation timing (in tics), so trust that, and just
+                    // use the current tic's fraction.
+                    // That said: adjusting animation speed complicates this slightly.  Consider the
+                    // player's walk animation, which takes 4 tics to complete, during which time we
+                    // cycle through 8 frames.  Playing that at half speed means only half the
+                    // animation actually plays, but if the player continues walking, then on the
+                    // NEXT four tics, we should play the other half.  To make this work, use the
+                    // tic as a global timer as well: if the animation started on tics 0-4, play the
+                    // first half; if it started on tics 5-8, play the second half.  They could get
+                    // out of sync if the player hesitates, but no one will notice that, and this
+                    // approach minimizes storing extra state.
+                    let i = (tile.animation_progress + tic % 1) / tile.animation_speed;
+                    // But do NOT do this for explosions or splashes, which have a fixed duration
+                    // and only play once
+                    if (this.animation_slowdown > 1 && ! tile.type.ttl) {
+                        // i ranges from [0, 1), but a slowdown of N means we'll only play the first
+                        // 1/N of it before the game ends (or loops) the animation.
+                        // So increase by [0..N-1] to get it in some other range, then divide by N
+                        // to scale back down to [0, 1)
+                        i += Math.floor(tic / tile.animation_speed % this.animation_slowdown);
+                        i /= this.animation_slowdown;
+                    }
+                    coords = coords[Math.floor(i * coords.length)];
+                }
+                else {
+                    // This tile animates on a global timer, one cycle every quarter of a second
+                    coords = coords[Math.floor(tic / this.animation_slowdown % 5 / 5 * coords.length)];
+                }
+            }
+            else {
+                coords = coords[0];
+            }
+        }
+
+        blit(coords[0], coords[1], ...mask);
+    }
+
+    _draw_letter(drawspec, tile, tic, blit) {
+        this._draw_standard(drawspec.base, tile, tic, blit);
+
+        let glyph = tile ? tile.overlaid_glyph : "?";
+        if (drawspec.letter_glyphs[glyph]) {
+            let [x, y] = drawspec.letter_glyphs[glyph];
+            // XXX size is hardcoded here, but not below, meh
+            blit(x, y, 0, 0, 0.5, 0.5, 0.25, 0.25);
+        }
+        else {
+            // Look for a range
+            let u = glyph.charCodeAt(0);
+            for (let rangedef of drawspec.letter_ranges) {
+                if (rangedef.range[0] <= u && u < rangedef.range[1]) {
+                    let t = u - rangedef.range[0];
+                    let x = rangedef.x0 + rangedef.w * (t % rangedef.columns);
+                    let y = rangedef.y0 + rangedef.h * Math.floor(t / rangedef.columns);
+                    blit(x, y, 0, 0, rangedef.w, rangedef.h,
+                        (1 - rangedef.w) / 2, (1 - rangedef.h) / 2);
+                    break;
+                }
+            }
+        }
+    }
+
+    _draw_logic_gate(drawspec, tile, tic, blit) {
+        // Layer 1: wiring state
+        // Always draw the unpowered wire base
+        let unpowered_coords = this.layout['#unpowered'];
+        let powered_coords = this.layout['#powered'];
+        blit(...unpowered_coords);
+        if (tile && tile.cell) {
+            // What goes on top varies a bit...
+            // FIXME implement for NOT and counter!
+            let r = this.layout['#wire-width'] / 2;
+            if (tile.cell.powered_edges & DIRECTIONS[tile.direction].bit) {
+                // Output (on top)
+                let [x0, y0, x1, y1] = this._rotate(tile.direction, 0.5 - r, 0, 0.5 + r, 0.5);
+                blit(powered_coords[0], powered_coords[1], x0, y0, x1 - x0, y1 - y0);
+            }
+            if (tile.cell.powered_edges & DIRECTIONS[DIRECTIONS[tile.direction].right].bit) {
+                // Right input, which includes the middle
+                let [x0, y0, x1, y1] = this._rotate(tile.direction, 0.5 - r, 0.5 - r, 1, 1);
+                blit(powered_coords[0], powered_coords[1], x0, y0, x1 - x0, y1 - y0);
+            }
+            if (tile.cell.powered_edges & DIRECTIONS[DIRECTIONS[tile.direction].left].bit) {
+                // Left input, which does not include the middle
+                let [x0, y0, x1, y1] = this._rotate(tile.direction, 0, 0.5 - r, 0.5 - r, 1);
+                blit(powered_coords[0], powered_coords[1], x0, y0, x1 - x0, y1 - y0);
+            }
+        }
+
+        // Layer 2: the tile itself
+        this._draw_standard(drawspec.logic_gate_tiles[tile.gate_type], tile, tic, blit);
+
+        // Layer 3: counter number
+        if (tile.gate_type === 'counter') {
+            blit(0, 3, tile.memory * 0.75, 0, 0.75, 1, 0.125, 0);
+        }
+    }
+
+    _draw_railroad(drawspec, tile, tic, blit) {
+        // All railroads have regular gravel underneath
+        // TODO would be nice to disambiguate since it's possible to have nothing visible
+        this._draw_standard(this.layout['gravel'], tile, tic, blit);
+
+        // FIXME what do i draw if there's no tile?
+        let part_order = ['ne', 'se', 'sw', 'nw', 'ew', 'ns'];
+        let visible_parts = [];
+        let topmost_part = null;
+        for (let [i, part] of part_order.entries()) {
+            if (tile && (tile.tracks & (1 << i))) {
+                if (tile.track_switch === i) {
+                    topmost_part = part;
+                }
+                visible_parts.push(part);
+            }
+        }
+
+        let has_switch = (tile && tile.track_switch !== null);
+        for (let part of visible_parts) {
+            this._draw_standard(drawspec.railroad_ties[part], tile, tic, blit);
+        }
+        let tracks = has_switch ? drawspec.railroad_inactive : drawspec.railroad_active;
+        for (let part of visible_parts) {
+            if (part !== topmost_part) {
+                this._draw_standard(tracks[part], tile, tic, blit);
+            }
+        }
+
+        if (topmost_part) {
+            this._draw_standard(drawspec.railroad_active[topmost_part], tile, tic, blit);
+        }
+        if (has_switch) {
+            this._draw_standard(drawspec.railroad_switch, tile, tic, blit);
+        }
    }

    // Draws a tile type, given by name.  Passing in a tile is optional, but
    // without it you'll get defaults.
-    draw_type(name, tile, tic, blit) {
+    draw_type(name, tile, tic, perception, blit) {
        let drawspec = this.layout[name];
        if (! drawspec) {
            console.error(`Don't know how to draw tile type ${name}!`);
@@ -615,12 +1054,17 @@ export class Tileset {

        if (drawspec.overlay) {
            // Goofy overlay thing used for green/purple toggle tiles and
-            // southeast thin walls.  Draw the base (a type name), then draw
+            // southeast thin walls.  Draw the base (a type name or drawspec), then draw
            // the overlay (either a type name or a regular draw spec).
            // TODO chance of infinite recursion here
-            this.draw_type(drawspec.base, tile, tic, blit);
+            if (typeof drawspec.base === 'string') {
+                this.draw_type(drawspec.base, tile, tic, perception, blit);
+            }
+            else {
+                this._draw_standard(drawspec.base, tile, tic, blit);
+            }
            if (typeof drawspec.overlay === 'string') {
-                this.draw_type(drawspec.overlay, tile, tic, blit);
+                this.draw_type(drawspec.overlay, tile, tic, perception, blit);
                return;
            }
            else {
@@ -628,6 +1072,30 @@ export class Tileset {
            }
        }

+        // TODO shift everything to use this style, this is ridiculous
+        if (drawspec.special) {
+            if (drawspec.special === 'letter') {
+                this._draw_letter(drawspec, tile, tic, blit);
+                return;
+            }
+            else if (drawspec.special === 'perception') {
+                if (perception >= drawspec.threshold) {
+                    drawspec = drawspec.revealed;
+                }
+                else {
+                    drawspec = drawspec.hidden;
+                }
+            }
+            else if (drawspec.special === 'logic-gate') {
+                this._draw_logic_gate(drawspec, tile, tic, blit);
+                return;
+            }
+            else if (drawspec.special === 'railroad') {
+                this._draw_railroad(drawspec, tile, tic, blit);
+                return;
+            }
+        }
+
        let coords = drawspec;
        if (drawspec.mask) {
            // Some tiles (OK, just the thin walls) don't actually draw a full
@@ -635,31 +1103,51 @@ export class Tileset {
            coords = drawspec.tile;
        }
        else if (drawspec.wired) {
-            if (tile && tile.wire_directions !== undefined && tile.wire_directions !== 0) {
-                // TODO all four is a different thing entirely
-                // Draw the appropriate wire underlay
-                this.draw_type('#unpowered', tile, tic, blit);
+            // This /should/ match CC2's draw order exactly, based on experimentation
+            let wire_radius = this.layout['#wire-width'] / 2;
+            if (tile && tile.wire_directions === 0x0f) {
+                // This is a wired tile with crossing wires, which acts a little differently
+                // Draw the base tile
+                blit(drawspec.base[0], drawspec.base[1]);

-                // Draw a masked part of the base tile
-                let wiredir = tile.wire_directions;
-                let wire_radius = this.layout['#wire-width'] / 2;
-                let wire0 = 0.5 - wire_radius;
-                let wire1 = 0.5 + wire_radius;
-                let [bx, by] = drawspec.base;
-                if ((wiredir & DIRECTIONS['north'].bit) === 0) {
-                    blit(bx, by, 0, 0, 1, wire0);
-                }
-                if ((wiredir & DIRECTIONS['south'].bit) === 0) {
-                    blit(bx, by + wire1, 0, wire1, 1, wire0);
-                }
-                if ((wiredir & DIRECTIONS['west'].bit) === 0) {
-                    blit(bx, by, 0, 0, wire0, 1);
-                }
-                if ((wiredir & DIRECTIONS['east'].bit) === 0) {
-                    blit(bx + wire1, by, wire1, 0, wire0, 1);
-                }
+                // Draw the two wires as separate rectangles, NS then EW
+                let wire_inset = 0.5 - wire_radius;
+                let wire_coords_ns = this.layout[
+                    tile.cell && tile.cell.powered_edges & DIRECTIONS['north'].bit ? '#powered' : '#unpowered'];
+                let wire_coords_ew = this.layout[
+                    tile.cell && tile.cell.powered_edges & DIRECTIONS['east'].bit ? '#powered' : '#unpowered'];
+                blit(wire_coords_ns[0], wire_coords_ns[1], wire_inset, 0, wire_radius * 2, 1);
+                blit(wire_coords_ew[0], wire_coords_ew[1], 0, wire_inset, 1, wire_radius * 2);

-                // Then draw the wired tile as normal
+                // Draw the cross tile on top
+                coords = drawspec.wired_cross ?? drawspec.wired;
+            }
+            else if (tile && tile.wire_directions) {
+                // Draw the base tile
+                blit(drawspec.base[0], drawspec.base[1]);
+
+                // Draw the wire part as a single rectangle, initially just a small dot in the
+                // center, but extending out to any edge that has a wire present
+                let x0 = 0.5 - wire_radius;
+                let x1 = 0.5 + wire_radius;
+                let y0 = 0.5 - wire_radius;
+                let y1 = 0.5 + wire_radius;
+                if (tile.wire_directions & DIRECTIONS['north'].bit) {
+                    y0 = 0;
+                }
+                if (tile.wire_directions & DIRECTIONS['east'].bit) {
+                    x1 = 1;
+                }
+                if (tile.wire_directions & DIRECTIONS['south'].bit) {
+                    y1 = 1;
+                }
+                if (tile.wire_directions & DIRECTIONS['west'].bit) {
+                    x0 = 0;
+                }
+                let wire_coords = this.layout[tile.cell && tile.cell.powered_edges ? '#powered' : '#unpowered'];
+                blit(wire_coords[0], wire_coords[1], x0, y0, x1 - x0, y1 - y0);
+
+                // Then draw the wired tile on top of it all
                coords = drawspec.wired;
            }
            else {
@@ -675,6 +1163,10 @@ export class Tileset {
                }
            }
        }
+        else if (drawspec.arrows) {
+            // Directional blocks have a specific overlay, but draw the base first
+            coords = drawspec.base;
+        }
        else if (drawspec.animate_width) {
            // Force floors animate their...  cutout, I guess?
            let [x, y] = drawspec.base;
@@ -695,7 +1187,7 @@ export class Tileset {
        }

        // Apply custom per-type visual states
-        if (TILE_TYPES[name].visual_state) {
+        if (TILE_TYPES[name] && TILE_TYPES[name].visual_state) {
            // Note that these accept null, too, and return a default
            let state = TILE_TYPES[name].visual_state(tile);
            // If it's a string, that's an alias for another state
@@ -759,41 +1251,70 @@ export class Tileset {
            // Continue on with masking
            coords = drawspec.tile;
            let [x0, y0, w, h] = drawspec.mask;
-            blit(coords[0] + x0, coords[1] + y0, x0, y0, w, h);
+            blit(coords[0], coords[1], x0, y0, w, h);
        }
        else {
            if (!coords) console.error(name, tile);
            blit(coords[0], coords[1]);
        }

-        // Special behavior for special objects
-        // TODO? hardcode this less?
-        if (name === 'floor_letter') {
-            let n = tile.ascii_code - 32;
-            let scale = 0.5;
-            let sx, sy;
-            if (n < 0) {
-                // Arrows
-                if (n < -4) {
-                    // Default to south
-                    n = -2;
-                }
+        // Wired tiles may also have tunnels, drawn on top of everything else
+        if (drawspec.wired && tile && tile.wire_tunnel_directions) {
+            let tunnel_coords = this.layout['#wire-tunnel'];
+            let tunnel_width = 6/32;
+            let tunnel_length = 12/32;
+            let tunnel_offset = (1 - tunnel_width) / 2;
+            if (tile.wire_tunnel_directions & DIRECTIONS['north'].bit) {
+                blit(tunnel_coords[0], tunnel_coords[1],
+                    tunnel_offset, 0, tunnel_width, tunnel_length);
+            }
+            if (tile.wire_tunnel_directions & DIRECTIONS['south'].bit) {
+                blit(tunnel_coords[0], tunnel_coords[1],
+                    tunnel_offset, 1 - tunnel_length, tunnel_width, tunnel_length);
+            }
+            if (tile.wire_tunnel_directions & DIRECTIONS['west'].bit) {
+                blit(tunnel_coords[0], tunnel_coords[1],
+                    0, tunnel_offset, tunnel_length, tunnel_width);
+            }
+            if (tile.wire_tunnel_directions & DIRECTIONS['east'].bit) {
+                blit(tunnel_coords[0], tunnel_coords[1],
+                    1 - tunnel_length, tunnel_offset, tunnel_length, tunnel_width);
+            }
+        }

-                let direction = ['north', 'east', 'south', 'west'][n + 4];
-                [sx, sy] = this.layout['floor_letter#arrows'][direction];
+        // Directional blocks have arrows drawn on top
+        // TODO does cc2 draw even if there are no arrows?
+        if (drawspec.arrows && tile && tile.arrows) {
+            let [x, y] = drawspec.arrows;
+            let x0 = 0.25, y0 = 0.25, x1 = 0.75, y1 = 0.75;
+            if (tile.arrows.has('north')) {
+                y0 = 0;
            }
-            else {
-                // ASCII text (only up through uppercase)
-                let letter_spec = this.layout['floor_letter#ascii'];
-                if (n > letter_spec.width / scale * letter_spec.height / scale) {
-                    n = 0;
-                }
-                let w = letter_spec.width / scale;
-                sx = (letter_spec.x0 + n % w) * scale;
-                sy = (letter_spec.y0 + Math.floor(n / w)) * scale;
+            if (tile.arrows.has('east')) {
+                x1 = 1;
            }
-            let offset = (1 - scale) / 2;
-            blit(sx, sy, offset, offset, scale, scale);
+            if (tile.arrows.has('south')) {
+                y1 = 1;
+            }
+            if (tile.arrows.has('west')) {
+                x0 = 0;
+            }
+            blit(x, y, x0, y0, x1 - x0, y1 - y0);
+        }
+    }
+
+    _rotate(direction, x0, y0, x1, y1) {
+        if (direction === 'east') {
+            return [1 - y1, x0, 1 - y0, x1];
+        }
+        else if (direction === 'south') {
+            return [1 - x1, 1 - y1, 1 - x0, 1 - y0];
+        }
+        else if (direction === 'west') {
+            return [y0, 1 - x1, y1, 1 - x0];
+        }
+        else {
+            return [x0, y0, x1, y1];
        }
    }
 }
@@ -1,7 +1,13 @@
+// Base class for custom errors
+export class LLError extends Error {}
+
+// Random choice
 export function random_choice(list) {
    return list[Math.floor(Math.random() * list.length)];
 }

+
+// DOM stuff
 function _mk(el, children) {
    if (children.length > 0) {
        if (!(children[0] instanceof Node) && children[0] !== undefined && typeof(children[0]) !== "string" && typeof(children[0]) !== "number") {
@@ -18,17 +24,86 @@ function _mk(el, children) {
 export function mk(tag_selector, ...children) {
    let [tag, ...classes] = tag_selector.split('.');
    let el = document.createElement(tag);
-    el.classList = classes.join(' ');
+    if (classes.length > 0) {
+        el.classList = classes.join(' ');
+    }
    return _mk(el, children);
 }

+export const SVG_NS = 'http://www.w3.org/2000/svg';
 export function mk_svg(tag_selector, ...children) {
    let [tag, ...classes] = tag_selector.split('.');
-    let el = document.createElementNS('http://www.w3.org/2000/svg', tag);
-    el.classList = classes.join(' ');
+    let el = document.createElementNS(SVG_NS, tag);
+    if (classes.length > 0) {
+        el.classList = classes.join(' ');
+    }
    return _mk(el, children);
 }

+export function handle_drop(element, options) {
+    let dropzone_class = options.dropzone_class ?? null;
+    let on_drop = options.on_drop;
+
+    let require_file = options.require_file ?? false;
+    let is_valid = ev => {
+        // TODO this requires files, should make some args for this
+        if (options.require_file) {
+            let dt = ev.dataTransfer;
+            if (! dt || dt.items.length === 0)
+                return false;
+
+            // Only test the first item I guess?  If it's a file then they should all be files
+            if (dt.items[0].kind !== 'file')
+                return false;
+        }
+
+        return true;
+    };
+
+    let end_drop = () => {
+        if (dropzone_class !== null) {
+            element.classList.remove(dropzone_class);
+        }
+    };
+
+    // TODO should have a filter function for when a drag is valid but i forget which of these
+    // should have that
+    element.addEventListener('dragenter', ev => {
+        if (! is_valid(ev))
+            return;
+
+        ev.stopPropagation();
+        ev.preventDefault();
+
+        if (dropzone_class !== null) {
+            element.classList.add(dropzone_class);
+        }
+    });
+    element.addEventListener('dragover', ev => {
+        if (! is_valid(ev))
+            return;
+
+        ev.stopPropagation();
+        ev.preventDefault();
+    });
+    element.addEventListener('dragleave', ev => {
+        if (ev.relatedTarget && element.contains(ev.relatedTarget))
+            return;
+
+        end_drop();
+    });
+    element.addEventListener('drop', ev => {
+        if (! is_valid(ev))
+            return;
+
+        ev.stopPropagation();
+        ev.preventDefault();
+
+        end_drop();
+        on_drop(ev);
+    });
+}
+
 export function promise_event(element, success_event, failure_event) {
    let resolve, reject;
    let promise = new Promise((res, rej) => {
@@ -36,21 +111,21 @@ export function promise_event(element, success_event, failure_event) {
        reject = rej;
    });

-    let success_handler = e => {
+    let success_handler = ev => {
        element.removeEventListener(success_event, success_handler);
        if (failure_event) {
            element.removeEventListener(failure_event, failure_handler);
        }

-        resolve(e);
+        resolve(ev);
    };
-    let failure_handler = e => {
+    let failure_handler = ev => {
        element.removeEventListener(success_event, success_handler);
        if (failure_event) {
            element.removeEventListener(failure_event, failure_handler);
        }

-        reject(e);
+        reject(ev);
    };

    element.addEventListener(success_event, success_handler);
@@ -61,6 +136,7 @@ export function promise_event(element, success_event, failure_event) {
    return promise;
 }

+
 export async function fetch(url) {
    let xhr = new XMLHttpRequest;
    let promise = promise_event(xhr, 'load', 'error');
@@ -68,11 +144,26 @@ export async function fetch(url) {
    xhr.responseType = 'arraybuffer';
    xhr.send();
    await promise;
+    if (xhr.status !== 200)
+        throw new Error(`Failed to load ${url} -- ${xhr.status} ${xhr.statusText}`);
    return xhr.response;
 }

+export function string_from_buffer_ascii(buf, start = 0, len) {
+    if (ArrayBuffer.isView(buf)) {
+        start += buf.byteOffset;
+        buf = buf.buffer;
+    }
+    return String.fromCharCode.apply(null, new Uint8Array(buf, start, len));
+}
+
+// Converts a string to a buffer, using NO ENCODING, assuming single-byte characters
+export function bytestring_to_buffer(bytestring) {
+    return Uint8Array.from(bytestring, c => c.charCodeAt(0)).buffer;
+}
+
 // Cast a line through a grid and yield every cell it touches
-export function* walk_grid(x0, y0, x1, y1) {
+export function* walk_grid(x0, y0, x1, y1, min_a, min_b, max_a, max_b) {
    // TODO if the ray starts outside the grid (extremely unlikely), we should
    // find the point where it ENTERS the grid, otherwise the 'while'
    // conditions below will stop immediately
@@ -112,27 +203,24 @@ export function* walk_grid(x0, y0, x1, y1) {
        step_a = -step_a;
        offset_x = 1 - offset_x;
    }
-    // Zero offset means we're on a grid line, so we're actually a full cell
-    // away from the next grid line
-    if (offset_x === 0) {
+    else if (offset_x === 0) {
+        // Zero offset means we're on a grid line, so we're a full cell away from the next grid line
+        // (if we're moving forward; if we're moving backward, the next cell really is 0 away)
        offset_x = 1;
    }
    let step_b = 1;
-    let offset_y = 1 - (y0  - b);
+    let offset_y = 1 - (y0 - b);
    if (dy < 0) {
        dy = -dy;
        step_b = -step_b;
        offset_y = 1 - offset_y;
    }
-    if (offset_y === 0) {
+    else if (offset_y === 0) {
        offset_y = 1;
    }

    let err = dy * offset_x - dx * offset_y;

-    let min_a = 0, min_b = 0;
-    // TODO get these passed in fool
-    let max_a = 31, max_b = 31;
    if (dx > dy) {
        // Main axis is x/a
        while (min_a <= a && a <= max_a && min_b <= b && b <= max_b) {
@@ -171,3 +259,103 @@ export function* walk_grid(x0, y0, x1, y1) {
        }
    }
 }
+window.walk_grid = walk_grid;
+// console.table(Array.from(walk_grid(13, 27.133854389190674, 12.90625, 27.227604389190674)))
+
+// Root class to indirect over where we might get files from
+// - a pool of uploaded in-memory files
+// - a single uploaded zip file
+// - a local directory provided via the webkit Entry api
+// - HTTP (but only for files we choose ourselves, not arbitrary ones, due to CORS)
+// Note that where possible, these classes lowercase all filenames, in keeping with C2G's implicit
+// requirement that filenames are case-insensitive  :/
+class FileSource {
+    constructor() {}
+
+    // Get a file's contents as an ArrayBuffer
+    async get(path) {}
+}
+// Files we have had uploaded one at a time (note that each upload becomes its own source)
+export class FileFileSource extends FileSource {
+    constructor(files) {
+        super();
+        this.files = {};
+        for (let file of files) {
+            this.files[(file.webkitRelativePath ?? file.name).toLowerCase()] = file;
+        }
+    }
+
+    get(path) {
+        let file = this.files[path.toLowerCase()];
+        if (file) {
+            return file.arrayBuffer();
+        }
+        else {
+            return Promise.reject(new Error(`No such file was provided: ${path}`));
+        }
+    }
+}
+// Regular HTTP fetch
+export class HTTPFileSource extends FileSource {
+    // Should be given a URL object as a root
+    constructor(root) {
+        super();
+        this.root = root;
+    }
+
+    get(path) {
+        let url = new URL(path, this.root);
+        return fetch(url);
+    }
+}
+// WebKit Entry interface
+// XXX this does not appear to work if you drag in a link to a directory but that is probably beyond
+// my powers to fix
+export class EntryFileSource extends FileSource {
+    constructor(entries) {
+        super();
+        this.files = {};
+        let file_count = 0;
+
+        let read_directory = async (directory_entry, dir_prefix) => {
+            let reader = directory_entry.createReader();
+            let all_entries = [];
+            while (true) {
+                let entries = await new Promise((res, rej) => reader.readEntries(res, rej));
+                all_entries.push.apply(all_entries, entries);
+                if (entries.length === 0)
+                    break;
+            }
+
+            await handle_entries(all_entries, dir_prefix);
+        };
+        let handle_entries = (entries, dir_prefix) => {
+            file_count += entries.length;
+            if (file_count > 4096)
+                throw new LLError("Found way too many files; did you drag in the wrong directory?");
+
+            let dir_promises = [];
+            for (let entry of entries) {
+                if (entry.isDirectory) {
+                    dir_promises.push(read_directory(entry, dir_prefix + entry.name + '/'));
+                }
+                else {
+                    this.files[(dir_prefix + entry.name).toLowerCase()] = entry;
+                }
+            }
+
+            return Promise.all(dir_promises);
+        };
+
+        this._loaded_promise = handle_entries(entries, '');
+    }
+
+    async get(path) {
+        let entry = this.files[path.toLowerCase()];
+        if (! entry)
+            throw new LLError(`No such file in local directory: ${path}`);
+
+        let file = await new Promise((res, rej) => entry.file(res, rej));
+        return await file.arrayBuffer();
+    }
+}
@@ -37,7 +37,10 @@ button {
    font-family: inherit;
    color: white;
    background: var(--button-bg-color);
-    border: none;
+    border: 1px solid hsl(225, 10%, 15%);
+    box-shadow:
+        inset 0 0 0 1px hsl(225, 10%, 33%),
+        0 1px 1px hsl(225, 10%, 10%);
    border-radius: 0.25em;
    text-transform: lowercase;
    cursor: pointer;
@@ -45,9 +48,19 @@ button {
 button:hover {
    background: var(--button-bg-hover-color);
 }
+button:active {
+    box-shadow:
+        inset 0 0 2px 1px hsl(225, 10%, 33%);
+    transform: translateY(1px);
+    /* Need this for the editor's tool help things and i'm not questioning it */
+    z-index: 1;
+}
 button:disabled {
    color: #606060;
    background: #202020;
+    box-shadow:
+        inset 0 0 2px 1px hsl(225, 0%, 10%),
+        0 1px 0 hsl(225, 10%, 10%);
    cursor: auto;
 }
 button.button-big {
@@ -82,6 +95,12 @@ p:first-child {
 p:last-child {
    margin-bottom: 0;
 }
+pre {
+    white-space: pre-wrap;
+}
+code {
+    color: #c0c0e0;
+}

 a {
    color: #c0c0c0;
@@ -91,10 +110,10 @@ a:visited {
    text-decoration: underline dotted;
 }
 a:link {
-    color: hsl(225, 50%, 60%);
+    color: hsl(225, 50%, 75%);
 }
 a:visited {
-    color: hsl(300, 50%, 60%);
+    color: hsl(255, 50%, 75%);
 }
 a:link:hover,
 a:visited:hover {
@@ -104,6 +123,16 @@ a:active {
    color: hsl(0, 50%, 60%);
 }

+svg.svg-icon {
+    width: 1em;
+    height: 1em;
+    vertical-align: middle;
+
+    stroke: none;
+    fill: currentColor;
+    fill-rule: evenodd;
+}
+
 /* Overlay styling */
 .overlay {
    display: flex;
@@ -117,6 +146,11 @@ a:active {
    right: 0;
    background: #fff4;
 }
+.overlay.--transient {
+    align-items: start;
+    justify-content: start;
+    background: none;
+}
 .dialog {
    display: flex;
    flex-direction: column;
@@ -154,6 +188,31 @@ a:active {
    overflow: auto;
    padding: 1em;
 }
+.dialog pre.error {
+    color: #400000;
+    background: #f0d0d0;
+    padding: 0.5em 1em;
+}
+.dialog a:link {
+    color: hsl(225, 50%, 50%);
+}
+.dialog a:visited {
+    color: hsl(255, 50%, 50%);
+}
+dl.formgrid {
+    display: grid;
+    grid: auto-flow min-content / 1fr 4fr;
+    align-items: baseline;
+    gap: 1em;
+    margin: 0;
+}
+dl.formgrid > dt {
+    grid-column: 1;
+}
+dl.formgrid > dd {
+    grid-column: 2;
+    margin: 0;
+}

 /* Individual overlays */
 table.level-browser {
@@ -188,6 +247,10 @@ table.level-browser tr.--unvisited {
    color: #606060;
    font-style: italic;
 }
+table.level-browser tr.--error {
+    color: #600000;
+    font-style: italic;
+}
 table.level-browser tbody tr {
    cursor: pointer;
 }
@@ -254,6 +317,13 @@ label.option .option-label {
    /* TODO */
 }

+@media (max-width: 800px) {
+    .dialog {
+        max-width: 90%;
+        max-height: 90%;
+    }
+}
+
 /* Bits and pieces */
 img.compat-icon {
    margin: 0 0.25em 0.125em;
@@ -281,7 +351,7 @@ body > header {
    align-items: center;
    gap: 0.5em;

-    margin: 0.25em;
+    padding: 0.5em;
    line-height: 1.125;
 }
 body > header h1 {
@@ -291,14 +361,13 @@ body > header h2 {
    font-size: 1.33em;
 }
 body > header h3 {
-    font-size: 1.25em;
+    font-size: 1.75em;
 }
 body > header > nav {
    flex: 1;
    display: flex;
    justify-content: flex-end;
    gap: 0.5em;
-    margin: 0.25rem 0.5rem;
 }
 body > header button {
    font-size: 0.75em;
@@ -317,8 +386,25 @@ body[data-mode=player] #editor-play {
    order: 3;
    color: #606060;
 }
-#header-level {
-    font-size: 1.5em;
+
+@media (max-width: 800px) {
+    body > header {
+        padding: 0.25em;
+    }
+    /* All these headings are way too big on phones */
+    body > header h1 {
+        font-size: 1.25em;
+    }
+    body > header h2 {
+        font-size: 1.125em;
+    }
+    body > header h3 {
+        font-size: 1.0625em;
+    }
+    body > header p {
+        /* "a game by eevee" takes up too much space :( */
+        display: none;
+    }
 }

 /**************************************************************************************************/
@@ -334,10 +420,31 @@ body[data-mode=player] #editor-play {
    ;
    gap: 1em;

+    position: relative;
    padding: 1em 10%;
    margin: auto;
    overflow: auto;
 }
+#splash > .drag-overlay {
+    display: none;
+    justify-content: center;
+    align-items: center;
+
+    font-size: 10vmin;
+    position: absolute;
+    top: 0;
+    bottom: 0;
+    left: 1rem;
+    right: 1rem;
+    background: #fff2;
+    border: 0.25rem dashed white;
+    border-radius: 1rem;
+    text-shadow: 0 1px 5px black;
+    text-align: center;
+}
+#splash.--drag-hover > .drag-overlay {
+    display: flex;
+}

 #splash > header {
    grid-area: header;
@@ -351,6 +458,11 @@ body[data-mode=player] #editor-play {
 #splash > header h1 {
    font-size: 3em;
 }
+#splash > header p {
+    margin: 0;
+    font-style: italic;
+    color: #909090;
+}
 #splash h2 {
    border-bottom: 1px solid #404040;
    color: #909090;
@@ -363,7 +475,7 @@ body[data-mode=player] #editor-play {
 }
 #splash > #splash-intro {
    grid-area: intro;
-    font-size: 18px;
+    font-size: 20px;
 }
 #splash > #splash-stock-levels {
    grid-area: stock;
@@ -371,7 +483,8 @@ body[data-mode=player] #editor-play {
 #splash > #splash-upload-levels {
    grid-area: upload;
 }
-#splash-upload {
+#splash-upload-file,
+#splash-upload-dir {
    /* Hide the file upload control, which is ugly */
    display: none;
 }
@@ -379,6 +492,23 @@ body[data-mode=player] #editor-play {
    grid-area: yours;
 }

+@media (max-width: 800px) {
+    #splash {
+        /* Grid layout doesn't fit, just stack everything */
+        display: flex;
+        flex-direction: column;
+        /* 10% padding is way way too much */
+        padding: 1em;
+    }
+    /* Shrink logo and title */
+    #splash > header img {
+        width: 48px;
+    }
+    #splash > header h1 {
+        font-size: 2em;
+    }
+}
+
 button.level-pack-button {
    display: grid;
    grid:
@@ -434,8 +564,9 @@ button.level-pack-button p {
        "level      bonus"      min-content
        "level      message"    1fr
        "level      inventory"  min-content
+        "level      actions"    min-content
        /* Need explicit min-content to force the hint to wrap */
-        / min-content min-content
+        / min-content min-content min-content
    ;
    column-gap: 2em;
    row-gap: 0.5em;
@@ -469,7 +600,7 @@ button.level-pack-button p {
    justify-content: center;
    align-items: center;

-    z-index: 1;
+    z-index: 2;
    font-size: calc(0.5 * var(--tile-width) * var(--scale));
    padding: 2%;
    background: #0009;
@@ -477,6 +608,10 @@ button.level-pack-button p {
    text-align: center;
    text-shadow: 0 2px 1px black;
 }
+/* Allow clicking through the overlay in debug mode */
+#player.--debug .overlay-message {
+    pointer-events: none;
+}
 #player .overlay-message p {
    margin: 0;
 }
@@ -552,7 +687,6 @@ dl.score-chart .-sum {
 .bonus output {
    flex: 1;
    font-size: 2em;
-    padding: 0.125em;
    min-width: 2em;
    min-height: 1em;
    line-height: 1;
@@ -584,9 +718,11 @@ dl.score-chart .-sum {
 }
 #player .bonus {
    visibility: hidden;
+    display: none;
 }
 #player.--bonus-visible .bonus {
    visibility: initial;
+    display: initial;
 }

 .message {
@@ -616,7 +752,7 @@ dl.score-chart .-sum {

    background-size: calc(var(--tile-width) * var(--scale)) calc(var(--tile-height) * var(--scale));
    width: calc(4 * var(--tile-width) * var(--scale));
-    min-height: calc(2 * var(--tile-height) * var(--scale));
+    height: calc(2 * var(--tile-height) * var(--scale));
 }
 #player .inventory img {
    width: calc(var(--tile-width) * var(--scale));
@@ -640,15 +776,27 @@ dl.score-chart .-sum {
    background: #0009;
    color: white;
 }
+#player .actions {
+    grid-area: actions;
+    display: flex;
+    gap: 0.5em;
+}
+#player .actions button {
+    flex: 1;
+    white-space: nowrap;
+}

 #player-music {
    grid-area: music;
    display: flex;
+    gap: 1em;
+    margin: 0 1em;
    text-transform: lowercase;
    color: #909090;
 }
 #player-music #player-music-left {
-    flex: 1 0 auto;
+    /* allow me to wrap if need be */
+    flex: 1 0 0px;
 }
 #player-music #player-music-right {
    text-align: right;
@@ -660,25 +808,111 @@ dl.score-chart .-sum {
 #player .controls {
    grid-area: controls;
    display: flex;
+    gap: 0.25em;
+    justify-content: space-between;
 }
-.play-controls,
-.demo-controls {
+#player button {
+    position: relative;
+}
+#player button .keyhint {
+    position: absolute;
+    left: 0;
+    right: 0;
+    top: -2em;
+    width: 1em;
+    margin: auto;
+    color: #404040;
+    border: 1px solid #202020;
+    border-radius: 0.25em;
+    box-shadow: 0 2px 0 #202020;
+    text-align: center;
+    text-transform: uppercase;
+}
+#player button:disabled .keyhint {
+    display: none;
+}
+
+.play-controls {
    display: flex;
+    align-items: center;
    gap: 0.25em;
 }
 .play-controls {
    align-self: start;
 }
-.demo-controls {
-    display: none;
-    flex: 1;
-    justify-content: flex-end;
-}
-main.--has-demo .demo-controls {
-    display: flex;
-}

 /* Debug stuff */
+#player.--debug #player-debug {
+    display: grid;
+}
+#player-debug {
+    display: none;
+    grid:
+        "time       inventory   options"
+        "buttons    buttons     buttons"
+        / 2fr 1fr 2fr
+    ;
+    gap: 0.25em;
+    padding: 0.5em;
+    background-image: repeating-linear-gradient(135deg,
+        hsl(0, 0%, 4%) 0em,
+        hsl(0, 0%, 4%) 1em,
+        hsl(15, 25%, 8%) 1em,
+        hsl(15, 25%, 8%) 2em);
+    border: 0.25em solid hsla(30, 100%, 50%, 0.5);
+    box-shadow: inset 0 0 0.25em 0.25em #0004;
+
+}
+#player-debug > .-time {
+    grid-area: time;
+}
+#player-debug > .-time table.-time-controls {
+}
+#player-debug > .-time table.-time-controls button {
+    width: 100%;
+    text-align: inherit;
+}
+#player-debug > .-time table.-time-controls td:nth-child(1) {
+    /* go backwards button */
+    text-align: left;
+}
+#player-debug > .-time table.-time-controls td:nth-child(2) {
+    /* value */
+    width: 6em;
+    text-align: right;
+}
+#player-debug > .-time table.-time-controls td:nth-child(3) {
+    /* label */
+}
+#player-debug > .-time table.-time-controls td:nth-child(4) {
+    /* go forward button */
+    text-align: right;
+}
+#player-debug > .-options {
+    grid-area: options;
+}
+#player-debug > .-inventory {
+    grid-area: inventory;
+    display: grid;
+    margin: auto;
+    grid: auto-fill var(--tile-height) / repeat(4, var(--tile-width));
+    gap: 2px;
+}
+#player-debug > .-inventory > button {
+    padding: 0;
+}
+#player-debug > .-inventory > button > img {
+    display: block;
+}
+#player-debug > .-inventory > button.-wide {
+    grid-column: span 4;
+    padding: 0.25em;
+}
+#player-debug > .-buttons {
+    grid-area: buttons;
+    display: flex;
+    gap: 0.25em;
+}
 .input {
    display: grid;
    display: none;
@@ -709,6 +943,57 @@ main.--has-demo .demo-controls {
 }


+@media (max-width: 800px) {
+    #player {
+        /* sentinel for js */
+        --is-portrait: 1;
+        /* The play area isn't necessarily the biggest thing any more, and it's ugly when stretched */
+        align-items: center;
+    }
+    #player .controls {
+        flex-direction: column;
+    }
+    #player > .-main-area {
+        /* Rearrange the grid to be vertical */
+        grid:
+            "level      level"
+            "chips      inventory" calc((var(--tile-height) * var(--scale) * 2 - 1em) / 3)
+            "time       inventory" calc((var(--tile-height) * var(--scale) * 2 - 1em) / 3)
+            "bonus      inventory" calc((var(--tile-height) * var(--scale) * 2 - 1em) / 3)
+            "actions    actions"   min-content
+            /* FIXME ideally the first column would be 1fr so the hearts/time have space, but that
+             * allows hints to grow to the entire width of the window, which incredibly sucks.  i
+             * don't know how to get around this except by giving the grid a fixed width, which i
+             * guess wouldn't be that hard */
+            / min-content min-content
+        ;
+        row-gap: 0.5em;
+        column-gap: 1em;
+
+        padding: 0.5em;
+    }
+    #player .inventory {
+        /* stick me in the center right */
+        place-self: center end;
+    }
+    #player .message {
+        /* Overlay hints on the inventory area */
+        grid-row: chips / bonus;
+        grid-column: level;
+        z-index: 1;
+        font-size: calc(var(--tile-height) * var(--scale) / 2.5);
+    }
+    #player .keyhint {
+        /* Hide key hints, they take up surprisingly a lot of space */
+        display: none;
+    }
+    #player-music {
+        /* Stack the title/artist on the volume, since they don't fit well side by side */
+        font-size: 0.875em;
+    }
+}
+
+
 /**************************************************************************************************/
 /* Editor */

@@ -716,47 +1001,136 @@ main.--has-demo .demo-controls {
    flex: 1 1 auto;
    display: grid;
    grid:
-        "controls   level" min-content
-        "palette    level" 1fr
-        / minmax(25%, auto) auto
+        "controls   controls"   min-content
+        "palette    level"      1fr
+        / min-content 1fr
    ;
    gap: 0.5em;

    min-height: 0;
-    margin: auto;
-    padding: 1em;
+    margin: auto 1em;
 }

-#editor .level {
+#editor .editor-canvas {
    grid-area: level;
-    position: relative;
    overflow: auto;
+    /* Flex layout to center the canvas and overlay together */
+    display: flex;
+    /* This isn't supported in Chrome (still!!), so use auto margins on the child instead
+    align-items: safe center;
+    justify-content: safe center;
+    */
+    background: #202020;
+    border: 0.125em solid black;
 }
+#editor .editor-canvas .-container {
+    position: relative;
+    margin: auto;
+    /* Give the canvas/overlay a bit of a margin; it has to be a border because, due to some quirk
+     * of overflowing flexboxes I guess, padding and margins won't extend the scroll area on the
+     * right and bottom */
+    /* TODO padding should be half a cell? */
+    border: 2em solid transparent;
+}
+#editor .editor-canvas canvas {
+    display: block;
+    width: calc(var(--viewport-width) * var(--tile-width) * var(--scale));
+    --viewport-width: 9;
+    --viewport-height: 9;
+}
+/* SVG overlays */
 #editor svg.level-editor-overlay {
    position: absolute;
    top: 0;
+    bottom: 0;
    left: 0;
-    /* FIXME get real size */
-    width: 1024px;
-    height: 1024px;
+    right: 0;
    /* allow clicks to go through us! */
    pointer-events: none;
-}
-#editor .level-editor-overlay rect.overlay-cxn {
+
+    /* default svg properties */
    stroke-width: 0.0625;
-    stroke: red;
    fill: none;
 }
-#editor .level-editor-overlay line.overlay-cxn {
-    stroke-width: 0.0625;
+#editor .level-editor-overlay rect.overlay-cxn {
    stroke: red;
 }
+#editor .level-editor-overlay line.overlay-cxn {
+    stroke: red;
+}
+#editor .level-editor-overlay rect.overlay-camera {
+    stroke: #808080;
+    fill: #80808040;
+    pointer-events: auto;
+}
+#editor .level-editor-overlay text {
+    /* Each cell is one "pixel", so text needs to be real small */
+    font-size: 1px;
+}
+#editor .level-editor-overlay text.overlay-edit-tip {
+    stroke: none;
+    fill: black;
+}

 #editor .controls {
+    /* TODO with the hint area gone i don't think this needs to be a grid?  could just flex */
    grid-area: controls;
+    display: grid;
+    grid:
+        "tile   toolbar    layer   direction   .       menu" auto
+        / auto auto auto auto 1fr auto
+    ;
+    align-items: center;
+    column-gap: 1em;
 }
-#editor .controls p img {
-    background: url(icons/tool-bg-unselected.png);
+#editor .controls #editor-tile {
+    grid-area: tile;
+}
+#editor .controls #editor-tile canvas {
+    display: block;
+}
+#editor .controls #editor-toolbar {
+    grid-area: toolbar;
+}
+#editor-toolbar .-help {
+    opacity: 0;
+    visibility: hidden;
+    z-index: 1;
+    position: absolute;
+    width: max-content;
+    margin-top: -0.25em;
+    margin-left: -0.5em;
+    padding: 0.33em 0.75em;
+    pointer-events: none;
+
+    border: 1px solid black;
+    white-space: pre-wrap;
+    line-height: 1.5;
+    text-transform: none;
+    text-align: left;
+    background: hsl(225, 10%, 20%);
+    box-shadow: 0 1px 2px 1px #0004;
+
+    transition-property: margin-top, opacity, visibility;
+    transition-timing-function: ease-out;
+    transition-duration: 0.125s, 0.125s, 0s;
+    transition-delay: 0s, 0s, 0.125s;
+}
+#editor-toolbar .-help h3 {
+    font-size: 1.25em;
+    margin-bottom: 0.25rem;
+    border-bottom: 1px solid currentColor;
+}
+#editor-toolbar button:hover .-help {
+    opacity: 1;
+    z-index: 2;  /* show above any that are in mid-fade */
+    visibility: visible;
+    margin-top: 0.25em;
+    transition-delay: 0.5s;
+    transition-timing-function: ease-in;
+}
+#editor .controls .-buttons {
+    grid-area: menu;
 }
 .icon-button-set {
    display: flex;
@@ -771,6 +1145,7 @@ main.--has-demo .demo-controls {
    background: url(icons/tool-bg-unselected.png) no-repeat;
    border: none;
    border-radius: 0;
+    box-shadow: none;
 }
 .icon-button-set button.-selected {
    background-image: url(icons/tool-bg-selected.png);
@@ -778,9 +1153,10 @@ main.--has-demo .demo-controls {
 .icon-button-set button img {
    display: block;
 }
+
 #editor .palette {
+    isolation: isolate;
    grid-area: palette;
-    min-width: 20vw;
    padding-right: 0.25em;  /* in case of scrollbar */
    overflow-y: auto;
 }
@@ -795,12 +1171,172 @@ main.--has-demo .demo-controls {
 }
 #editor .palette section {
    display: grid;
-    grid: auto-flow 32px / repeat(auto-fit, 32px);
-    gap: 3px;
+    margin: 0.33em 4px;  /* matches gap */
+    grid: auto-flow 32px / repeat(8, 32px);
+    gap: 4px;
 }
 .palette-entry {
-    margin: 0.25em;
+}
+.palette-entry:hover {
+    box-shadow: 0 0 0 1px black, 0 0 0 3px hsl(225, 100%, 75%);
 }
 .palette-entry.--selected {
-    box-shadow: 0 0 0 1px black, 0 0 0 2px white;
+    z-index: 1;
+    box-shadow: 0 0 0 1px black, 0 0 0 3px white;
+}
+
+.editor-level-browser {
+    display: grid;
+    grid: auto-flow auto / repeat(auto-fill, minmax(13em, 1fr));  /* 12em preview wdith + padding */
+    gap: 0.5em;
+    width: 70vw;
+    /* seems to go into the parent's right padding fsr, i guess because the scrollbar is there */
+    margin-right: 1em;
+    list-style: none;
+}
+.editor-level-browser li {
+    display: grid;
+    grid:
+        "preview    preview"
+        "number     title"
+        / min-content 1fr
+    ;
+    gap: 0.25em;
+    padding: 0.5em;
+}
+.editor-level-browser li:hover {
+    background: hsl(225, 60%, 85%);
+}
+.editor-level-browser li > .-preview {
+    grid-area: preview;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    width: 12em;
+    height: 12em;
+    margin: auto;
+}
+.editor-level-browser li > .-preview:empty::before {
+    content: '···';
+    display: block;
+    font-size: 5em;
+    color: #c0c0c0;
+}
+.editor-level-browser li > .-preview canvas {
+    display: block;
+    max-width: 100%;
+    max-height: 100%;
+}
+.editor-level-browser li > .-number {
+    grid-area: number;
+    font-size: 2em;
+}
+.editor-level-browser li > .-title {
+    grid-area: title;
+    align-self: center;
+}
+
+/* Mini editors for specific tiles with complex properties */
+/* FIXME should this stuff be on an overlay container class? */
+form.editor-popup-tile-editor {
+    position: relative;
+    padding: 0.5em;
+    color: black;
+    background: white;
+    border: 1px solid black;
+    box-shadow: 0 2px 4px #0004;
+
+    margin-top: 1em;
+
+    --chevron-offset: 0px;
+}
+form.editor-popup-tile-editor.--above {
+    margin-top: -1em;
+}
+form.editor-popup-tile-editor h3 {
+    border-bottom: 1px dotted #606060;
+}
+form.editor-popup-tile-editor * + h3 {
+    margin-top: 0.25em;
+}
+/* Use ::before for a chevron pointing at the tile in question */
+form.editor-popup-tile-editor::before {
+    content: '';
+    display: block;
+    position: absolute;
+    border: 1em solid transparent;
+    left: var(--chevron-offset);
+    margin-left: -1em;
+
+    top: -1em;
+    border-top: none;
+    border-bottom-color: white;
+    filter: drop-shadow(0 -1px 0 black);
+}
+form.editor-popup-tile-editor.--above::before {
+    top: auto;
+    bottom: -1em;
+    border: 1em solid transparent;
+    border-bottom: none;
+    border-top-color: white;
+    filter: drop-shadow(0 1px 0 black);
+}
+/* Letter floor tiles, which let you pick the character to use; show them as a grid.  Note the
+ * characters are preceded by radio buttons, which we hide for simplicity */
+ol.editor-letter-tile-picker {
+    display: grid;
+    grid: auto-flow 1.5em / repeat(17, 1.5em);
+    text-align: center;
+    font-family: monospace;
+}
+ol.editor-letter-tile-picker label,
+ol.editor-letter-tile-picker .-glyph {
+    display: block;
+    height: 100%;
+}
+ol.editor-letter-tile-picker input[type=radio] {
+    display: none;
+}
+ol.editor-letter-tile-picker input[type=radio]:checked + .-glyph {
+    background: hsl(225, 75%, 90%);
+    outline: 2px solid hsl(225, 75%, 80%);
+}
+/* Hint tiles accept prose */
+textarea.editor-hint-tile-text {
+    font-size: 1.5em;
+    width: 20vw;
+    height: 20vh;
+    min-width: 15rem;
+    min-height: 5rem;
+    border: none;
+    font-family: serif;
+}
+/* Class for a list that uses hidden inputs with svg icons, shared by directional blocks and
+ * railroad tracks */
+.editor-tile-editor-svg-parts input {
+    display: none;
+}
+.editor-tile-editor-svg-parts svg {
+    display: block;
+    width: 3em;
+    fill: none;
+    stroke: #c0c0c0;
+    stroke-width: 2;
+}
+.editor-tile-editor-svg-parts input:checked + svg {
+    stroke: hsl(225, 90%, 50%);
+}
+/* Directional blocks have arrows */
+ol.editor-directional-block-tile-arrows {
+    display: grid;
+    grid: auto-flow 3em / repeat(3, 3em);
+}
+/* Railroad tracks are...  complicated */
+ul.editor-railroad-tile-tracks {
+    display: grid;
+    grid: auto-flow 3em / repeat(3, 3em);
+    gap: 0.25em;
+}
+ul.editor-railroad-tile-tracks.--switch input:checked + svg {
+    stroke: hsl(15, 90%, 50%);
 }