PixAnvil/Three.js demo
JavaScript doesn't seem to be running, so nothing below is going to work.
Setup
Animate
Save
// Make a bunch of spheres var g=new THREE.SphereGeometry(1, 8, 6); var m=new THREE.MeshLambertMaterial( {color: 0xffffff}) sim.nspheres=5; sim.spheres=[]; for (var i=0;i<sim.nspheres;i++) { var s=new THREE.Mesh(g,m); s.position.set(0,0,0); s.V=new vec3(+20.0*Math.random(),Math.random(),+15.0*Math.random()); s.P=new vec3(-3.0,0,0); s.castShadow=true; s.receiveShadow=true; scene.add(s); // so it gets rendered sim.spheres[i]=s; // so we can animate it } // Ground sim.ground = new THREE.Mesh( new THREE.CubeGeometry(20,20,2), new THREE.MeshLambertMaterial( {color: 0xff6622, opacity: 1}) ); sim.ground.position.z=-2; /* puts top edge at z=-1 */ sim.ground.receiveShadow=true; scene.add(sim.ground); // Sun-like spotlight var l=new THREE.SpotLight(); sim.light = l; l.position.set( -10, -20, 20 ); l.castShadow=true; l.shadowCameraNear = 1; l.shadowCameraFar = 100; l.shadowCameraFov = 45; scene.add(l); camera.lookAt(scene.position);
/** s: sphere object, with s.P position and s.V velocity. N: surface normal, facing out of region. P: point on surface of boundary region. */ function boundaryBounce(s,N,P) { N.normalize(); var rP=s.P.clone().subSelf(P); // sphere position, relative to boundary var d=rP.dot(N); if (d>0.0) { // we hit the boundary s.P.addSelf(N.clone().multiplyScalar(-d)); // move inside var dV=s.V.dot(N); if (dV>0.0) { // flip velocity s.V.addSelf(N.clone().multiplyScalar(-2.0*dV )); } s.V.multiplyScalar(0.6); // bounce friction (inelastic) if (dV>0.3) { // CLANG! the camera camera.position.addSelf(N.clone().multiplyScalar(-dV*0.005)); } } } camera.position.set(0,-10,1.7); // default: assume no "clang!". for (var i=0;i<sim.nspheres;i++) { var s=sim.spheres[i]; var A=new vec3(0,0,-9.8); s.V.addSelf(A.clone().multiplyScalar(lib.dt)); s.P.addSelf(s.V.clone().multiplyScalar(lib.dt)); boundaryBounce(s,new vec3(0,0,-1), new vec3()); // floor boundaryBounce(s,new vec3(+1,0,0), new vec3(5,0,0)); boundaryBounce(s,new vec3(-1,0,0), new vec3(-4,0,0)); boundaryBounce(s,new vec3(0,0,+1), new vec3(0,0,5)); // lid s.position=s.P; // copy to 3D display }
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/* Content here coming soon! */ For now, just copy out your Setup and Animate code.