refactor

app/src/physics.ts

@@ -0,0 +1,115 @@
+import * as THREE from 'three'
+import * as CANNON from 'cannon-es'
+
+export class PhysicsManager {
+  static setupPhysicsWorld(): CANNON.World {
+    const world = new CANNON.World()
+    
+    // Setup physics world
+    world.gravity.set(0, 0, 0)
+    
+    // Use SAPBroadphase for better collision detection with many objects
+    world.broadphase = new CANNON.SAPBroadphase(world)
+    
+    // Enable collision detection and response
+    world.allowSleep = false // Prevent objects from sleeping
+    
+    // Configure contact material for better collisions
+    const defaultMaterial = new CANNON.Material('default')
+    const defaultContactMaterial = new CANNON.ContactMaterial(defaultMaterial, defaultMaterial, {
+      friction: 0.4,
+      restitution: 0.3,
+      contactEquationStiffness: 1e8,
+      contactEquationRelaxation: 3,
+      frictionEquationStiffness: 1e8,
+      frictionEquationRelaxation: 3
+    })
+    world.addContactMaterial(defaultContactMaterial)
+    world.defaultMaterial = defaultMaterial
+
+    return world
+  }
+
+  static updatePhysics(
+    world: CANNON.World,
+    physicsObjects: Array<{ mesh: THREE.Object3D; body: CANNON.Body }>,
+    attractionPoint: THREE.Vector3,
+    mouseWorldPosition: THREE.Vector3,
+    deltaTime: number
+  ): void {
+    // Use a smaller, more stable timestep for better collision detection
+    const fixedTimeStep = 1/60 // 60 Hz - more stable than 120 Hz
+    const maxSubSteps = 5 // Increased substeps for better collision accuracy
+    
+    world.step(fixedTimeStep, deltaTime, maxSubSteps)
+
+    // Apply forces to objects
+    physicsObjects.forEach((obj) => {
+      // Attraction to center point
+      const attractionForce = new CANNON.Vec3()
+      attractionForce.x = attractionPoint.x - obj.body.position.x
+      attractionForce.y = attractionPoint.y - obj.body.position.y
+      attractionForce.z = attractionPoint.z - obj.body.position.z
+      
+      const distance = Math.sqrt(
+        attractionForce.x * attractionForce.x +
+        attractionForce.y * attractionForce.y +
+        attractionForce.z * attractionForce.z
+      )
+      
+      if (distance > 0) {
+        const strength = 16.0 / (distance * distance + 1) // Reduced from 8.0 to prevent objects moving too fast
+        attractionForce.scale(strength, attractionForce)
+        obj.body.force.set(
+          obj.body.force.x + attractionForce.x,
+          obj.body.force.y + attractionForce.y,
+          obj.body.force.z + attractionForce.z
+        )
+      }
+
+      // Mouse repulsion
+      const repulsionForce = new CANNON.Vec3()
+      repulsionForce.x = obj.body.position.x - mouseWorldPosition.x
+      repulsionForce.y = obj.body.position.y - mouseWorldPosition.y
+      repulsionForce.z = obj.body.position.z - mouseWorldPosition.z
+      
+      const mouseDistance = Math.sqrt(
+        repulsionForce.x * repulsionForce.x +
+        repulsionForce.y * repulsionForce.y +
+        repulsionForce.z * repulsionForce.z
+      )
+      
+      if (mouseDistance < 3 && mouseDistance > 0) {
+        const repulsionStrength = 5.0 / (mouseDistance * mouseDistance + 0.1)
+        repulsionForce.scale(repulsionStrength, repulsionForce)
+        obj.body.force.set(
+          obj.body.force.x + repulsionForce.x,
+          obj.body.force.y + repulsionForce.y,
+          obj.body.force.z + repulsionForce.z
+        )
+        
+        // Debug log to verify mouse repulsion is working
+        console.log('Mouse repulsion applied, distance:', mouseDistance.toFixed(2), 'strength:', repulsionStrength.toFixed(2))
+        
+        // Add rotational torque from mouse interaction
+        const torque = new CANNON.Vec3(
+          (Math.random() - 0.5) * repulsionStrength * 0.1,
+          (Math.random() - 0.5) * repulsionStrength * 0.1,
+          (Math.random() - 0.5) * repulsionStrength * 0.1
+        )
+        obj.body.torque.set(
+          obj.body.torque.x + torque.x,
+          obj.body.torque.y + torque.y,
+          obj.body.torque.z + torque.z
+        )
+      }
+
+      // Apply damping
+      obj.body.velocity.scale(0.99, obj.body.velocity)
+
+      // Update mesh position to match physics body
+      obj.mesh.position.copy(obj.body.position as any)
+      obj.mesh.quaternion.copy(obj.body.quaternion as any)
+    })
+  }
+}