feat(babylon_setup): add first person camera

Co-authored-by: Copilot <copilot@github.com>

src/babylon_setup.js

@@ -24,16 +24,29 @@ const engine = new BABYLON.Engine(canvas, true);
 const scene = new BABYLON.Scene(engine);
 scene.clearColor = new BABYLON.Color4(0.05, 0.07, 0.1, 1);
 
-const camera = new BABYLON.ArcRotateCamera(
-    "cam",
-    -Math.PI / 2,
-    Math.PI / 2.4,
-    10,
-    BABYLON.Vector3.Zero(),
-    scene,
-);
+const camera = new BABYLON.UniversalCamera("cam", new BABYLON.Vector3(0, 1.6, 0), scene);
+camera.minZ = 0.1;
+camera.speed = 1.12;
+camera.angularSensibility = 1000;
+camera.inertia = 0.6;
+camera.keysUp = [87]; // W
+camera.keysDown = [83]; // S
+camera.keysLeft = [65]; // A
+camera.keysRight = [68]; // D
+camera.checkCollisions = true;
+camera.applyGravity = true;
+camera.ellipsoid = new BABYLON.Vector3(0.35, 0.9, 0.35);
 camera.attachControl(canvas, true);
 
+scene.gravity = new BABYLON.Vector3(0, -0.2, 0);
+scene.collisionsEnabled = true;
+
+canvas.addEventListener("click", () => {
+    if (document.pointerLockElement !== canvas) {
+        canvas.requestPointerLock();
+    }
+});
+
 new BABYLON.HemisphericLight("light", new BABYLON.Vector3(0, 1, 0), scene);
 
 // Placeholder sphere
@@ -65,6 +78,7 @@ let chestMap = new Map(); // key: "x,y" -> {mesh, opened}
 let keyChestKey = null;
 let exitBox = null;
 let exitGridPos = null; // track exit grid position for collision checking
+let spawnMarker = null;
 const cellSize = 2;
 
 function clearLevelMeshes() {
@@ -75,6 +89,7 @@ function clearLevelMeshes() {
     chestMap.clear();
     keyChestKey = null;
     if (exitBox) { try { exitBox.dispose(); } catch(e){}; exitBox = null; }
+    if (spawnMarker) { try { spawnMarker.dispose(); } catch(e){}; spawnMarker = null; }
     exitGridPos = null;
 }
 
@@ -155,6 +170,7 @@ function buildLevelFromGrid(grid) {
 
     const floor = BABYLON.MeshBuilder.CreateGround('levelGround', { width: w*cellSize, height: h*cellSize }, scene);
     floor.position = new BABYLON.Vector3(0, 0, 0);
+    floor.checkCollisions = true;
     const fm = new BABYLON.StandardMaterial('floorMat', scene);
     fm.diffuseColor = new BABYLON.Color3(0.08, 0.08, 0.09);
     floor.material = fm;
@@ -236,12 +252,23 @@ function placeExit(grid, seed) {
     const halfH = (grid.length * cellSize) / 2;
     const ex = x*cellSize - halfW + cellSize/2;
     const ez = y*cellSize - halfH + cellSize/2;
+    
+    // Ground plane indicator
     const plane = BABYLON.MeshBuilder.CreateGround('exitZone', { width: cellSize*0.9, height: cellSize*0.9 }, scene);
     plane.material = new BABYLON.StandardMaterial('exitMat', scene);
     plane.material.emissiveColor = new BABYLON.Color3(0.9, 0.8, 0.2);
     plane.position = new BABYLON.Vector3(ex, 0.01, ez);
     exitBox = plane;
     levelMeshes.push(plane);
+    
+    // Tall pillar for visibility
+    const pillar = BABYLON.MeshBuilder.CreateCylinder('exitPillar', { diameter: cellSize*0.3, height: cellSize*3.0 }, scene);
+    const pillarMat = new BABYLON.StandardMaterial('exitPillarMat', scene);
+    pillarMat.diffuseColor = new BABYLON.Color3(0.95, 0.8, 0.1);
+    pillarMat.emissiveColor = new BABYLON.Color3(0.3, 0.25, 0.05);
+    pillar.material = pillarMat;
+    pillar.position = new BABYLON.Vector3(ex, cellSize*0.75, ez);
+    levelMeshes.push(pillar);
 }
 
 function spawnCameraAt(grid) {
@@ -262,11 +289,26 @@ function spawnCameraAt(grid) {
             const halfH = (h * cellSize) / 2;
             const px = x*cellSize - halfW + cellSize/2;
             const pz = y*cellSize - halfH + cellSize/2;
+            
             try {
                 if (camera && camera.position) {
                     camera.position = new BABYLON.Vector3(px, 1.6, pz);
                 }
             } catch (e) {}
+            
+            // Add spawn marker sphere
+            if (spawnMarker) {
+                try { spawnMarker.dispose(); } catch(e) {}
+            }
+            const marker = BABYLON.MeshBuilder.CreateSphere('spawnMarker', { diameter: cellSize*0.4 }, scene);
+            const markerMat = new BABYLON.StandardMaterial('spawnMarkerMat', scene);
+            markerMat.diffuseColor = new BABYLON.Color3(0.2, 0.6, 0.95);
+            markerMat.emissiveColor = new BABYLON.Color3(0.1, 0.3, 0.5);
+            marker.material = markerMat;
+            marker.position = new BABYLON.Vector3(px, cellSize*0.2, pz);
+            spawnMarker = marker;
+            levelMeshes.push(marker);
+            
             return;
         }
     }