Add rope bridge example

examples/src/examples/physics/rope-bridge.example.mjs

@@ -0,0 +1,267 @@
+import { deviceType, rootPath, fileImport } from 'examples/utils';
+import * as pc from 'playcanvas';
+
+const { CameraControls } = await fileImport(`${rootPath}/static/scripts/camera-controls.mjs`);
+
+const canvas = /** @type {HTMLCanvasElement} */ (document.getElementById('application-canvas'));
+window.focus();
+
+pc.WasmModule.setConfig('Ammo', {
+    glueUrl: `${rootPath}/static/lib/ammo/ammo.wasm.js`,
+    wasmUrl: `${rootPath}/static/lib/ammo/ammo.wasm.wasm`,
+    fallbackUrl: `${rootPath}/static/lib/ammo/ammo.js`
+});
+await new Promise((resolve) => {
+    pc.WasmModule.getInstance('Ammo', () => resolve());
+});
+
+const gfxOptions = {
+    deviceTypes: [deviceType],
+    glslangUrl: `${rootPath}/static/lib/glslang/glslang.js`,
+    twgslUrl: `${rootPath}/static/lib/twgsl/twgsl.js`
+};
+
+const device = await pc.createGraphicsDevice(canvas, gfxOptions);
+device.maxPixelRatio = Math.min(window.devicePixelRatio, 2);
+
+const createOptions = new pc.AppOptions();
+createOptions.graphicsDevice = device;
+createOptions.keyboard = new pc.Keyboard(document.body);
+
+createOptions.componentSystems = [
+    pc.CameraComponentSystem,
+    pc.CollisionComponentSystem,
+    pc.JointComponentSystem,
+    pc.LightComponentSystem,
+    pc.RenderComponentSystem,
+    pc.RigidBodyComponentSystem,
+    pc.ScriptComponentSystem
+];
+createOptions.resourceHandlers = [
+    pc.ScriptHandler
+];
+
+const app = new pc.AppBase(canvas);
+app.init(createOptions);
+
+// Set the canvas to fill the window and automatically change resolution to be the same as the canvas size
+app.setCanvasFillMode(pc.FILLMODE_FILL_WINDOW);
+app.setCanvasResolution(pc.RESOLUTION_AUTO);
+
+// Ensure canvas is resized when window changes size
+const resize = () => app.resizeCanvas();
+window.addEventListener('resize', resize);
+app.on('destroy', () => {
+    window.removeEventListener('resize', resize);
+});
+
+// Start the app and create the scene
+app.start();
+
+// Create materials
+const woodMaterial = new pc.StandardMaterial();
+woodMaterial.diffuse = new pc.Color(0.7, 0.5, 0.3);
+woodMaterial.update();
+
+const anchorMaterial = new pc.StandardMaterial();
+anchorMaterial.diffuse = new pc.Color(0.3, 0.3, 0.3);
+anchorMaterial.update();
+
+// Create the camera
+const camera = new pc.Entity('Camera');
+camera.addComponent('camera', {
+    clearColor: new pc.Color(0.5, 0.5, 0.8)
+});
+camera.addComponent('script');
+camera.setLocalPosition(0, 7, 10);
+app.root.addChild(camera);
+
+camera.script.create(CameraControls, {
+    attributes: {
+        focusPoint: new pc.Vec3(0, 3, 0),
+        sceneSize: 10
+    }
+});
+
+// Create the light
+const light = new pc.Entity('Light');
+light.addComponent('light', {
+    type: 'directional',
+    castShadows: true,
+    shadowBias: 0.2,
+    shadowDistance: 40,
+    normalOffsetBias: 0.05,
+    shadowResolution: 2048
+});
+light.setEulerAngles(45, 30, 0);
+app.root.addChild(light);
+
+function createGround() {
+    const ground = new pc.Entity();
+    ground.addComponent('render', { type: 'plane' });
+    ground.addComponent('rigidbody', {
+        type: 'static',
+        restitution: 0.5
+    });
+    ground.addComponent('collision', {
+        type: 'box',
+        halfExtents: new pc.Vec3(20, 0.5, 10),
+        linearOffset: new pc.Vec3(0, -0.5, 0)
+    });
+    ground.setLocalScale(40, 1, 20);
+    app.root.addChild(ground);
+}
+
+// Create a bridge with physics joints
+function createBridge(startPos, endPos, segments) {
+    const plankWidth = 0.5;    // Width along X axis (spacing between planks)
+    const plankHeight = 0.1;   // Height along Y axis
+    const plankLength = 2;     // Length along Z axis (across the bridge)
+
+    const plankPos = startPos.clone();
+    plankPos.x += plankWidth / 2;
+
+    // Create bridge planks with minimal spacing
+    const planks = [];
+    for (let i = 0; i < segments; i++) {
+        // Create the physics plank with no scaling
+        const plank = new pc.Entity();
+        plank.addComponent('rigidbody', {
+            type: 'dynamic',
+            mass: 0.5,
+            friction: 0.6,
+            restitution: 0.1
+        });
+        plank.addComponent('collision', {
+            type: 'box',
+            halfExtents: new pc.Vec3(plankWidth/2, plankHeight/2, plankLength/2)
+        });
+
+        // Position the plank
+        plank.setLocalPosition(plankPos);
+        plankPos.x += plankWidth;
+
+        // Create a child entity for the visual representation
+        const visualPlank = new pc.Entity('visual');
+        visualPlank.addComponent('render', {
+            type: 'box',
+            material: woodMaterial
+        });
+        visualPlank.setLocalScale(plankWidth, plankHeight, plankLength);
+        plank.addChild(visualPlank);
+
+        app.root.addChild(plank);
+        planks.push(plank);
+    }
+
+    // Connect planks with joints
+    const jointPos = startPos.clone();
+    jointPos.x += plankWidth;
+
+    for (let i = 0; i < segments - 1; i++) {
+        const joint = new pc.Entity();
+
+        // Position the joint at the center of plankA
+        joint.setLocalPosition(jointPos);
+        jointPos.x += plankWidth;
+
+        joint.addComponent('joint', {
+            entityA: planks[i],
+            entityB: planks[i + 1],
+            enableCollision: false
+        });
+        app.root.addChild(joint);
+    }
+
+    // Create fixed anchor points in space
+    function createFixedPoint(pos, plank) {
+        const joint = new pc.Entity();
+        joint.setLocalPosition(pos);
+
+        joint.addComponent('joint', {
+            entityA: plank,          // Only connect to the plank
+            entityB: null,           // No second entity needed for fixed point
+            enableCollision: false,
+            angularMotionZ: pc.MOTION_FREE
+        });
+        app.root.addChild(joint);
+    }
+
+    // Create fixed points at start and end
+    createFixedPoint(startPos, planks[0]);
+    createFixedPoint(endPos, planks[planks.length - 1]);
+}
+
+// Create towers at the ends of the bridge
+function createTower(position) {
+    const towerWidth = 2;
+    const towerHeight = 6;
+    const towerDepth = 2;
+
+    const tower = new pc.Entity('Tower');
+    tower.addComponent('rigidbody', {
+        type: 'static'
+    });
+    tower.addComponent('collision', {
+        type: 'box',
+        halfExtents: new pc.Vec3(towerWidth/2, towerHeight/2, towerDepth/2)
+    });
+
+    const visualTower = new pc.Entity('visual');
+    visualTower.addComponent('render', {
+        type: 'box',
+        material: anchorMaterial
+    });
+    visualTower.setLocalScale(towerWidth, towerHeight, towerDepth);
+    tower.addChild(visualTower);
+
+    const towerPos = new pc.Vec3(position.x, position.y - 3, position.z);
+    tower.setLocalPosition(towerPos);
+    app.root.addChild(tower);
+}
+
+// Create bridge and towers
+const towerWidth = 2;
+
+// Calculate bridge connection points at tower sides and plank edges
+const bridgeStart = new pc.Vec3(-5, 5, 0);  // Right side of left tower + half plank
+const bridgeEnd = new pc.Vec3(5, 5, 0);     // Left side of right tower - half plank
+
+createGround();
+createTower(new pc.Vec3(-5 - towerWidth/2, 5, 0));
+createTower(new pc.Vec3(5 + towerWidth/2, 5, 0));
+createBridge(bridgeStart, bridgeEnd, 20);
+
+// Create a test sphere to drop on the bridge
+function createTestSphere(position) {
+    const sphere = new pc.Entity();
+    sphere.addComponent('render', {
+        type: 'sphere'
+    });
+    sphere.addComponent('rigidbody', {
+        type: 'dynamic',
+        mass: 5,
+        friction: 0.5,
+        restitution: 0.3
+    });
+    sphere.addComponent('collision', {
+        type: 'sphere',
+        radius: 0.5
+    });
+    sphere.setLocalPosition(position);
+    app.root.addChild(sphere);
+    return sphere;
+}
+
+// Add a sphere that can be dropped with spacebar
+let testSphere = null;
+app.keyboard.on('keydown', (event) => {
+    if (event.key === pc.KEY_SPACE) {
+        if (testSphere) {
+            testSphere.destroy();
+        }
+        testSphere = createTestSphere(new pc.Vec3(0, 10, 0));
+    }
+});
+
+export { app };