Add Sample 1709 Movement Models Lab to compare direct movement, tank controls, and optional weighted movement with camera follow and visible mode labels.

PR: BUILD_PR_LEVEL_17_39_SAMPLE_1709_MOVEMENT_MODELS_LAB

Author: DavidQ

docs/dev/CODEX_COMMANDS.md

@@ -1,3 +1,3 @@
 MODEL: GPT-5.3-codex
 REASONING: high
-COMMAND: Build full mini-game sample using existing engine systems and package to <project folder>/tmp/BUILD_PR_LEVEL_17_38_REAL_GAMEPLAY_SAMPLE.zip
+COMMAND: Create Sample 1709 Movement Models Lab using existing engine systems only. Demonstrate direct x/y movement, rotation/tank controls, and optionally weighted movement if already supportable. Add camera follow, visible mode labels, register the sample in samples/index.html, and package the repo-structured result to <project folder>/tmp/BUILD_PR_LEVEL_17_39_SAMPLE_1709_MOVEMENT_MODELS_LAB.zip

docs/dev/COMMIT_COMMENT.txt

@@ -1,3 +1,3 @@
-Implement real gameplay sample demonstrating full engine integration including rendering, input, camera, and debug systems.
+Add Sample 1709 Movement Models Lab to compare direct movement, tank controls, and optional weighted movement with camera follow and visible mode labels.
 
-PR: BUILD_PR_LEVEL_17_38_REAL_GAMEPLAY_SAMPLE
+PR: BUILD_PR_LEVEL_17_39_SAMPLE_1709_MOVEMENT_MODELS_LAB

docs/dev/reports/validation_checklist.txt

@@ -1,5 +1,7 @@
-- [ ] game runs
-- [ ] player movement works
-- [ ] camera follows
-- [ ] scoring/objective works
-- [ ] debug panels active
+- [ ] sample loads from samples/index.html
+- [ ] direct x/y movement works
+- [ ] tank/rotation movement works
+- [ ] optional weighted movement works if implemented
+- [ ] camera follows correctly in all active modes
+- [ ] active mode label/instructions visible
+- [ ] no console errors

docs/pr/BUILD_PR_LEVEL_17_39_SAMPLE_1709_MOVEMENT_MODELS_LAB.md

@@ -0,0 +1,37 @@
+# BUILD_PR_LEVEL_17_39_SAMPLE_1709_MOVEMENT_MODELS_LAB
+
+## Purpose
+Implement Sample 1709 as a movement-models lab using existing engine systems only.
+
+## Source of Truth
+- `docs/pr/PLAN_PR_LEVEL_17_39_SAMPLE_1709_MOVEMENT_MODELS_LAB.md`
+- existing Level 17 sample structure (`samples/phase-17/1701` to `1708`)
+
+## Exact Build Target
+1. Add sample `samples/phase-17/1709/` with:
+   - `index.html`
+   - `main.js`
+   - one scene file for movement models lab
+2. Demonstrate in-scene movement models:
+   - direct axis movement
+   - rotation/tank controls
+   - weighted movement (if supportable within sample scope)
+3. Include:
+   - camera follow behavior
+   - visible active-mode labeling and concise control hints
+   - deterministic mode switching controls
+4. Register `1709` in `samples/index.html`.
+5. Add targeted runtime validation for:
+   - launcher link presence
+   - distinct behavior across movement modes
+   - camera follow updates and mode label visibility
+
+## Non-Goals
+- no engine-core changes
+- no new shared debug framework features
+- no refactors to existing Level 17 samples
+- no roadmap status updates
+
+## Packaging Rule
+Package only this PR's created/modified files into:
+`tmp/BUILD_PR_LEVEL_17_39_SAMPLE_1709_MOVEMENT_MODELS_LAB.zip`

docs/pr/PLAN_PR_LEVEL_17_39_SAMPLE_1709_MOVEMENT_MODELS_LAB.md

@@ -0,0 +1,21 @@
+# PLAN_PR_LEVEL_17_39_SAMPLE_1709_MOVEMENT_MODELS_LAB
+
+## Purpose
+Add a focused Level 17 sample that compares movement models without polluting Sample 1708.
+
+## Scope
+Create Sample 1709 - Movement Models Lab demonstrating:
+- direct x/y movement
+- rotation/tank-style movement
+- optional physics-weighted movement
+
+## Requirements
+- camera follows controlled entity
+- on-screen label shows active movement mode
+- movement mode switching is obvious and testable
+- sample remains educational and isolated
+
+## Out of Scope
+- new engine systems
+- changes to Sample 1708
+- broad control refactors

samples/index.html

@@ -509,6 +509,7 @@ <h2>Phase 17 - Rendering Technique Expansion</h2>
         <a class="live" href="./phase-17/1706/index.html" title="Minecraft-style filled voxel terrain blocks with visible height variation." data-tags="camera3d, minecraft-style, voxel, terrain, filled-render, scene, themetokens" data-primary="minecraft-voxel-terrain">Sample 1706 - Minecraft Voxel Terrain</a>
         <a class="live" href="./phase-17/1707/index.html" title="Minecraft-style voxel chunk-window streaming around a movable camera anchor." data-tags="camera3d, minecraft-style, voxel, chunk-streaming, filled-render, scene, themetokens" data-primary="minecraft-chunk-streaming">Sample 1707 - Minecraft Chunk Streaming</a>
         <a class="live" href="./phase-17/1708/index.html" title="Real 3D mini-game loop with movement, hazard interaction, objective scoring, camera follow, and standard 3D debug panels." data-tags="camera3d, gameplay, objective, hazards, debug-panels, scene, themetokens" data-primary="real-gameplay-mini-game">Sample 1708 - Real Gameplay Mini-Game</a>
+        <a class="live" href="./phase-17/1709/index.html" title="Compares direct axis movement, tank rotation controls, and weighted movement with follow-camera framing." data-tags="camera3d, movement-models, direct-controls, tank-controls, weighted-motion, scene, themetokens" data-primary="movement-models-lab">Sample 1709 - Movement Models Lab</a>
       </div>
     </section>
     <section>