diff --git a/index.html b/index.html
index a20f8c6..2197b42 100644
--- a/index.html
+++ b/index.html
@@ -157,12 +157,13 @@
                     </select>
                 </p>
                 <ul>
-                    <li><input type="checkbox" disabled> Show actor info</li>
-                    <li><input type="checkbox" disabled> Show actor bounding boxes</li>
-                    <li><input type="checkbox" disabled> Freeze time for everything else</li>
-                    <li><input type="checkbox" disabled> Player is immortal</li>
-                    <li><input type="checkbox" disabled> Player ignores collision</li>
-                    <li><input type="checkbox" disabled> Player levitates</li>
+                    <li><label><input type="checkbox" disabled> Show actor info</label></li>
+                    <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> 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>
diff --git a/js/main.js b/js/main.js
index 0253395..44c47bd 100644
--- a/js/main.js
+++ b/js/main.js
@@ -418,6 +418,7 @@ class Player extends PrimaryView {
         });
         */
 
+        this.use_interpolation = true;
         this.renderer = new CanvasRenderer(this.conductor.tileset);
         this.level_el.append(this.renderer.canvas);
         this.renderer.canvas.addEventListener('auxclick', ev => {
@@ -647,7 +648,6 @@ class Player extends PrimaryView {
         this._advance_bound = this.advance.bind(this);
         this._redraw_bound = this.redraw.bind(this);
         // Used to determine where within a tic we are, for animation purposes
-        this.tic_offset = 0;
         this.last_advance = 0;  // performance.now timestamp
 
         // Auto-size the level canvas on resize
@@ -756,6 +756,21 @@ class Player extends PrimaryView {
             }),
         );
 
+        // Link up some options checkboxes
+        let wire_checkbox = (name, onclick) => {
+            let checkbox = debug_el.elements[name];
+            checkbox.checked = false;  // override browser memory
+            checkbox.addEventListener('click', onclick);
+        };
+        wire_checkbox('show_actor_bboxes', ev => {
+            this.renderer.show_actor_bboxes = ev.target.checked;
+            this._redraw();
+        });
+        wire_checkbox('disable_interpolation', ev => {
+            this.use_interpolation = ! ev.target.checked;
+            this._redraw();
+        });
+
         this.update_ui();
     }
 
@@ -824,7 +839,6 @@ class Player extends PrimaryView {
         this.set_state('waiting');
 
         this.turn_mode = this.turn_based_checkbox.checked ? 1 : 0;
-        this.tic_offset = 0;
         this.last_advance = 0;
         this.demo_faucet = null;
         this.current_keyring = {};
@@ -1048,19 +1062,23 @@ class Player extends PrimaryView {
         // TODO this is not gonna be right while pausing lol
         // TODO i'm not sure it'll be right when rewinding either
         // TODO or if the game's speed changes.  wow!
+        let tic_offset;
         if (this.turn_mode === 2) {
             // We're frozen in mid-tic, so the clock hasn't advanced yet, but everything has already
             // finished moving; pretend we're already on the next tic
-            this.tic_offset = 1;
+            tic_offset = 1;
         }
-        else {
-            this.tic_offset = Math.min(0.9999, (performance.now() - this.last_advance) / 1000 * TICS_PER_SECOND * this.play_speed);
+        else if (this.use_interpolation) {
+            tic_offset = Math.min(0.9999, (performance.now() - this.last_advance) / 1000 * TICS_PER_SECOND * this.play_speed);
             if (this.state === 'rewinding') {
-                this.tic_offset = 1 - this.tic_offset;
+                tic_offset = 1 - tic_offset;
             }
         }
+        else {
+            tic_offset = 0;
+        }
 
-        this._redraw();
+        this._redraw(tic_offset);
 
         // Check for a stopped game *after* drawing, so that if the game ends, we still draw its
         // final result before stopping the draw loop
@@ -1073,9 +1091,10 @@ class Player extends PrimaryView {
         }
     }
 
-    // Actually redraw.  Used to force drawing outside of normal play
-    _redraw() {
-        this.renderer.draw(this.tic_offset);
+    // Actually redraw.  Used to force drawing outside of normal play, in which case we don't
+    // interpolate (because we're probably paused)
+    _redraw(tic_offset = 0) {
+        this.renderer.draw(tic_offset);
     }
 
     render_inventory_tile(name) {
diff --git a/js/renderer-canvas.js b/js/renderer-canvas.js
index 315b5c8..0200bce 100644
--- a/js/renderer-canvas.js
+++ b/js/renderer-canvas.js
@@ -25,6 +25,7 @@ export class CanvasRenderer {
         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
     }
@@ -184,6 +185,20 @@ export class CanvasRenderer {
             }
         }
 
+        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);
         }