Spawn primitives with physics from scripts

apps/syncd-primitive-ball.js

@@ -0,0 +1,178 @@
+// Networked primitive with ownership model
+// Similar to the tumbleweed example - any player can grab control
+
+const SEND_RATE = 1 / 8
+const v1 = new Vector3()
+
+// Create a physics-enabled primitive
+const ball = world.sphere({
+  radius: 0.5,
+  rigidbody: {
+    type: 'dynamic',
+    mass: 0.5,
+    linearDamping: 0.1,
+    angularDamping: 0.5,
+    onContactStart: (e) => {
+      // When a player touches the ball, they take ownership
+      if (e.playerId && e.playerId === world.networkId) {
+        ownerId = world.networkId
+        app.send('take', ownerId)
+      }
+    }
+  }
+})
+
+// Position it somewhere visible
+ball.position.set(0, 2, -5)
+ball.material.color = '#ff00ff'
+ball.material.emissiveIntensity = 0.3
+
+let ownerId = null
+let lastSent = 0
+
+if (world.isClient) {
+  // Wait for initial state from server
+  if (app.state.ready) {
+    init(app.state)
+  } else {
+    app.on('state', init)
+  }
+
+  function init(state) {
+    // Apply initial state
+    ball.position.fromArray(state.p)
+    ball.quaternion.fromArray(state.q)
+    ball.setLinearVelocity(v1.fromArray(state.v))
+
+    // Set up interpolation for smooth movement
+    const npos = new LerpVector3(ball.position, SEND_RATE)
+    const nqua = new LerpQuaternion(ball.quaternion, SEND_RATE)
+
+    // Handle ownership changes
+    app.on('take', (newOwnerId) => {
+      if (ownerId === newOwnerId) return
+      ownerId = newOwnerId
+      npos.snap()
+      nqua.snap()
+
+      // Visual feedback for ownership
+      if (ownerId === world.networkId) {
+        ball.material.color = '#00ff00' // Green when you own it
+      } else if (ownerId) {
+        ball.material.color = '#ff0000' // Red when someone else owns it
+      } else {
+        ball.material.color = '#ff00ff' // Purple when no owner
+      }
+    })
+
+    // Receive position updates
+    app.on('move', (e) => {
+      if (ownerId === world.networkId) return // Ignore if we own it
+      npos.pushArray(e.p)
+      nqua.pushArray(e.q)
+      ball.setLinearVelocity(v1.fromArray(e.v))
+    })
+
+    // Update loop
+    app.on('update', (delta) => {
+      if (ball.sleeping) return
+
+      if (ownerId === world.networkId) {
+        // We own it - send updates
+        lastSent += delta
+        if (lastSent > SEND_RATE) {
+          lastSent = 0
+          app.send('move', {
+            p: ball.position.toArray(),
+            q: ball.quaternion.toArray(),
+            v: ball.getLinearVelocity(v1).toArray(),
+          })
+        }
+      } else {
+        // Someone else owns it - interpolate
+        npos.update(delta)
+        nqua.update(delta)
+      }
+    })
+  }
+
+  // Allow kicking the ball when you own it
+  world.on('keydown', (event) => {
+    if (event.key === ' ' && ownerId === world.networkId) {
+      const force = new Vector3(
+        (Math.random() - 0.5) * 10,
+        10,
+        (Math.random() - 0.5) * 10
+      )
+      ball.addForce(force, 'impulse')
+    }
+  })
+}
+
+if (world.isServer) {
+  // Initialize state
+  app.state.ready = true
+  app.state.p = ball.position.toArray()
+  app.state.q = ball.quaternion.toArray()
+  app.state.v = [0, 0, 0]
+  app.send('state', app.state)
+
+  // Handle ownership changes
+  app.on('take', (newOwnerId, networkId) => {
+    ownerId = newOwnerId
+    app.send('take', newOwnerId) // Broadcast to all clients
+  })
+
+  // Relay position updates
+  app.on('move', (e, networkId) => {
+    // Only accept moves from the current owner
+    if (networkId !== ownerId) return
+
+    app.state.p = e.p
+    app.state.q = e.q
+    app.state.v = e.v
+    ball.position.fromArray(e.p)
+    ball.quaternion.fromArray(e.q)
+    ball.setLinearVelocity(v1.fromArray(e.v))
+    app.send('move', e, networkId) // Send to all except sender
+  })
+
+  // Handle player disconnection
+  world.on('leave', (e) => {
+    if (e.player.networkId === ownerId) {
+      ownerId = null
+      app.send('take', null)
+    }
+  })
+
+  // Server takes control when no one owns it
+  app.on('update', (delta) => {
+    if (ball.sleeping) return
+
+    if (!ownerId) {
+      lastSent += delta
+      if (lastSent > SEND_RATE) {
+        app.state.p = ball.position.toArray()
+        app.state.q = ball.quaternion.toArray()
+        app.state.v = ball.getLinearVelocity(v1).toArray()
+        app.send('move', {
+          p: app.state.p,
+          q: app.state.q,
+          v: app.state.v,
+        })
+        lastSent = 0
+      }
+    }
+  })
+}
+
+// Cleanup
+app.on('destroy', () => {
+  app.off('state')
+  app.off('take')
+  app.off('move')
+  app.off('update')
+  world.off('keydown')
+  world.off('leave')
+  world.remove(ball)
+})

docs/README.md

@@ -4,4 +4,7 @@ These docs are for 3D artists and developers looking to build assets and/or full
 
 - [Commands](/docs/commands.md)
 - [Models](/docs/models.md)
-- [Scripts](/docs/scripts.md)
+- [Scripts](/docs/scripts.md)
+- [Primitives](/docs/primitives.md)
+- [HYP Format](/docs/hyp-format.md)
+- [Blender Exporter](/docs/blender-exporter.md)