Why is this simple THREE.js javascript particle system not working? - javascript

Are there any errors is this code? I am using a new version of Chrome to test on. I've written a similar program that displays a wireframe cube, with no issues. It ran well. I'm thinking I may have written or structured my code incorrectly.
var scene = new THREE.Scene();
var camera = new THREE.PerspectiveCamera(50,window.innerWidth/window.innerHeight, 1, 10000);
var renderer = new THREE.WebGLRenderer();
renderer.setSize(window.innerWidth, window.innerHeight);
document.body.appendChild(renderer.domElement);
// create the particle variables
var particleCount = 1000;
var particles = new THREE.Geometry();
var pMaterial = new THREE.ParticleBasicMaterial({
color: 'red',
size: 20
});
// create the individual particles
for (var p = 0; p < particleCount; p++) {
var pX = Math.random()*500 - 250;
var pY = Math.random()*500 - 250;
var pZ = Math.random()*500 - 250;
var particle = new THREE.Vertex(
new THREE.Vector3(pX, pY, pZ)
);
particles.vertices.push(particle);
}
// create the particle system
var particleSystem = new THREE.ParticleSystem(
particles,
pMaterial);
// add the particle system to the scene
scene.add(particleSystem);
function render() {
particleSystem.rotation.y += 0.01;
renderer.render(scene, camera);
requestAnimationFrame(render);
}
render();
I'm not seeing any results, so to speak - just a black canvas element on the page.

Your code looks outdated -- as if you copied something from the net, or from an outdated book.
Update to the current version of three.js, and learn from the current three.js examples.
Create your particles like so:
var particle = new THREE.Vector3( pX, pY, pZ );
Also, ParticleSystem is now PointCloud, and ParticleBasicMaterial is now PointCloudMaterial.
three.js r.69

Related

Why is my canvas element showing only a black screen?

I'm setting up a 3d asset viewer in Three.js. I'm running the code on a Plesk server provided by the university and have it linked via Dreamweaver. I'm a total newbie to JS and it was suggested in many threads and posts that I wrap my code within an 'init();' function. Up doing so, and clearing any errors that the code had, it is now showing a black screen, rather than the 3d model it would show before.
I've spent the whole day error checking removing problems that I was having which included the 'canvas' not being created inside the 'container' div, and the 'onWindowResize' function. All these problems have been resolved, and there are no errors in the code apparently. I've got ambient lights in the code and there was a working skybox, so I'm sure its not a problem with position of camera or lack of lighting.
I know that you need as little code as possible, but I have no idea where the problem is coming from, so a majority of the code on the page is here :
<div id="container" ></div>
<script>
let container;
let camera;
let controls;
let scene;
let renderer;
init();
animate;
function init(){
// Renderer - WebGL is primary Renderer for Three.JS
var renderer = new THREE.WebGLRenderer({antialias : true});
renderer.setClearColor(0xEEEEEE, 0.5);
// Selects and applies parameters to the 'Container' div
var container = document.querySelector("#container");
container.appendChild(renderer.domElement);
renderer.setSize(container.clientWidth, container.clientHeight);
// Perspective Camera (FOV, aspect ratio based on container, near, far)
var camera = new THREE.PerspectiveCamera( 75, container.clientWidth / container.clientHeight, 0.1, 1000);
camera.position.x = 750;
camera.position.y = 500;
camera.position.z = 1250;
// Scene will contain all objects in the world
var scene = new THREE.Scene();
//Lighting (Colour, intensity)
var light1Ambient = new THREE.AmbientLight(0xffffff , 0.3);
scene.add(light1Ambient);
var light1Point = new THREE.PointLight(0xfff2c1, 0.5, 0, 2);
scene.add(light1Point);
var light2Point = new THREE.PointLight(0xd6e3ff, 0.4, 0, 2);
scene.add(light2Point);
// All basic Geomety
var newPlane = new THREE.PlaneGeometry(250,250,100,100);
const mesh = new THREE.Mesh(
new THREE.BoxGeometry(1, 1, 1),
new THREE.MeshBasicMaterial( {color: 0x00ff00} )
);
scene.add(mesh);
// Water
water = new THREE.Water(newPlane,
{
textureWidth: 512,
textureHeight: 512,
waterNormals: new THREE.TextureLoader().load( 'http://up826703.ct.port.ac.uk/CTPRO/textures/waternormals.jpg', function ( texture ) {
texture.wrapS = texture.wrapT = THREE.RepeatWrapping;
} ),
alpha: 1.0,
sunDirection: light1Point.position.clone().normalize(),
sunColor: 0xffffff,
waterColor: 0x001e0f,
distortionScale: 0.5,
fog: scene.fog !== undefined
}
);
water.rotation.x = - Math.PI / 2;
scene.add( water );
// All Materials (Normal for Debugging) (Lambert: color)
var material = new THREE.MeshLambertMaterial({color: 0xF3FFE2});
var materialNew = new THREE.MeshBasicMaterial( {color: 0x00ff00} );
// Skybox
var skybox = new THREE.BoxGeometry(1000,1000, 1000);
var skyboxMaterials =
[
new THREE.MeshBasicMaterial({map: new THREE.TextureLoader().load("http://up826703.ct.port.ac.uk/CTPRO/skybox/blue/bluecloud_ft.jpg"), side: THREE.DoubleSide }),
new THREE.MeshBasicMaterial({map: new THREE.TextureLoader().load("http://up826703.ct.port.ac.uk/CTPRO/skybox/blue/bluecloud_bk.jpg"), side: THREE.DoubleSide }),
new THREE.MeshBasicMaterial({map: new THREE.TextureLoader().load("http://up826703.ct.port.ac.uk/CTPRO/skybox/blue/bluecloud_up.jpg"), side: THREE.DoubleSide }),
new THREE.MeshBasicMaterial({map: new THREE.TextureLoader().load("http://up826703.ct.port.ac.uk/CTPRO/skybox/blue/bluecloud_dn.jpg"), side: THREE.DoubleSide }),
new THREE.MeshBasicMaterial({map: new THREE.TextureLoader().load("http://up826703.ct.port.ac.uk/CTPRO/skybox/blue/bluecloud_rt.jpg"), side: THREE.DoubleSide }),
new THREE.MeshBasicMaterial({map: new THREE.TextureLoader().load("http://up826703.ct.port.ac.uk/CTPRO/skybox/blue/bluecloud_lf.jpg"), side: THREE.DoubleSide }),
];
var skyboxMaterial = new THREE.MeshFaceMaterial(skyboxMaterials);
var skyMesh = new THREE.Mesh (skybox, skyboxMaterial);
scene.add(skyMesh);
//Grid Helper Beneath Ship
scene.add(new THREE.GridHelper(250, 250));
//OBJ Model Loading
var objLoader = new THREE.OBJLoader();
objLoader.load('http://up826703.ct.port.ac.uk/CTPRO/models/ship1.obj', function(object){
scene.add(object);
});
// Object positioning
water.position.y = -2.5;
// Misc Positioning
light1Point.position.z =20;
light1Point.position.x = 25;
// z - front-back position
light2Point.position.z = -400;
// x - left-right
light2Point.position.x = -25;
// y - up- down
light2Point.position.y = 250;
window.addEventListener("resize", onWindowResize, false);
function onWindowResize() {
camera.aspect = window.innerWidth / window.innerHeight;
camera.updateProjectionMatrix();
renderer.setSize(container.clientWidth, container.clientHeight);
};
};
// Canvas adapts size based on changing windows size
//Render loop
var animate = function(){
water.material.uniforms[ "time" ].value += 1.0 / 120.0;
function drawFrame(ts){
var center = new THREE.Vector2(0,0);
window.requestAnimationFrame(drawFrame);
var vLength = newPlane.geometry.vertices.length;
for (var i = 0; i < vLength; i++) {
var v = newPlane.geometry.vertices[i];
var dist = new THREE.Vector2(v.x, v.y).sub(center);
var size = 2.0;
var magnitude = 8;
v.z = Math.sin(dist.length()/-size + (ts/900)) * magnitude;
}
newPlane.geometry.verticesNeedUpdate = true;
};
requestAnimationFrame(animate)
renderer.render(scene, camera);
controls.update();
}
</script>
I'm no professional, so I'm sorry if this is super rough for those of you with experience!
I need to point out, before wrapping all of this in the init(); function, it was working perfectly.
When working, I should see a crudely modeled ship sitting in some water, with a cloud skybox. The controls were working and it would auto rotate.
Right now it does none of this. The obj loader is working as seen in the chrome console log OBJLoader: 1661.970703125ms but again, nothing is actually displayed, it's just a black screen.
Thanks to anyone who's able to help me out with this!
this line
animate;
needs to a function call
animate();
Also you probably need to change the code below where you create the animate function from
var animate = function(){
To this
function animate(){
The reason is named functions are defined when the code is loaded but variables var are created when the code is executed. So with code like this
init();
animate();
var animate = function(){ ...
animate doesn't actually exist at the point the code tries to call it whereas with this
init();
animate();
function animate(){ ...
it does exist
You could also re-arrange the code so for example define animate before you use it should work.
var animate = function(){
...
};
init();
animate();
It also appear some are declared inside init which means that are not available to animate. So for example
var renderer = new THREE.WebGLRenderer({antialias : true});
declares a new variable renderer that only init can see. You wanted to set the renderer variable that is outside of init so change the code to
renderer = new THREE.WebGLRenderer({antialias : true});
controls is never defined so you probably need to define it or comment out
controls.update();
to
// controls.update();
note: you might find these tutorials helpful although if you're new to JavaScript you should probably spend time learning JavaScript

Three.js - Map multiple images to a sphere and control each one

I have a 3D sphere that I want to map an array of images onto, and I want to be able to control each individual image i.e. fading out/in each image independently. I'll provide an example image of what I'm trying to achieve as I feel like that's the best way to explain it.
So as you can see above, 8 images per column and 16(?) per row.
I have been able to recreate the above image by simply mapping that image to a SphereGeometry, however I would like to be able to dynamically swap out images, and fade them in at different times.
What I've tried so far / My ideas:
I tried pushing 8 test images to an array and using that as the material map, and then looping through each face of the SphereGeometry and assigning a material index of 1 through 8 and then resetting after every 8 using modulo, but that didn't work:
function createGlobe() {
var geomGlobe = new THREE.SphereGeometry(40, 32, 16);
var l = geomGlobe.faces.length;
imageArray.push(new THREE.MeshBasicMaterial({map: texture1}));
imageArray.push(new THREE.MeshBasicMaterial({map: texture2}));
imageArray.push(new THREE.MeshBasicMaterial({map: texture3}));
imageArray.push(new THREE.MeshBasicMaterial({map: texture4}));
imageArray.push(new THREE.MeshBasicMaterial({map: texture5}));
imageArray.push(new THREE.MeshBasicMaterial({map: texture6}));
imageArray.push(new THREE.MeshBasicMaterial({map: texture7}));
imageArray.push(new THREE.MeshBasicMaterial({map: texture8}));
for (var i = 0; i < l; i++) {
geomGlobe.faces[i].materialIndex = i % 8;
}
Globe = new THREE.Mesh(geomGlobe, imageArray);
scene.add(Globe);
}
I think I need to count every 4 or 8 faces and then set the material
index for each one of those faces to be the same so that they all use
the same image, but I'm not sure if the faces line up correctly in
that way.
So essentially what I need:
A way to dynamically add images to a sphere in an 8 per column, 16 per row fashion, and the ability to manipulate each one of those images individually.
Any help is very appreciated because I'm very stuck!
I recommend making a large canvas and using that as your texture, then animating your transitions into the canvas, followed by setting texture.needsUpdate = true to update it on the GPU.
You may find that the texture updating takes too much time.. in which case, you could try making 2 canvasses+spheres.. and crossfade between them by changing the frontmost ones opacity.
Below is a snippet showing one way to fade one sphere into another with some randomly filled canvasses..
var renderer = new THREE.WebGLRenderer();
var w = 300;
var h = 200;
renderer.setSize(w, h);
document.body.appendChild(renderer.domElement);
var scene = new THREE.Scene();
var camera = new THREE.PerspectiveCamera(
45, // Field of view
w / h, // Aspect ratio
0.1, // Near
10000 // Far
);
camera.position.set(15, 10, 15);
camera.lookAt(scene.position);
controls = new THREE.OrbitControls(camera, renderer.domElement);
var light = new THREE.PointLight(0xFFFF00);
light.position.set(20, 20, 20);
scene.add(light);
var light1 = new THREE.AmbientLight(0x808080);
light1.position.set(20, 20, 20);
scene.add(light1);
var light2 = new THREE.PointLight(0x00FFFF);
light2.position.set(-20, 20, -20);
scene.add(light2);
var light3 = new THREE.PointLight(0xFF00FF);
light3.position.set(-20, -20, -20);
scene.add(light3);
var sphereGeom = new THREE.SphereGeometry(5, 16, 16);
function rnd(rng) {
return (Math.random() * rng)
}
function irnd(rng) {
return rnd(rng) | 0
}
function randomCanvasTexture(sz) {
var canv = document.createElement('canvas');
canv.width = canv.height = sz;
var ctx = canv.getContext('2d')
for (var i = 0; i < 100; i++) {
ctx.fillStyle = `rgb(${irnd(256)},${irnd(256)},${irnd(256)})`
ctx.fillRect(irnd(sz), irnd(sz), 32, 32)
}
var tex = new THREE.Texture(canv);
tex.needsUpdate = true;
return tex;
}
var material = new THREE.MeshLambertMaterial({
color: 0x808080,
map: randomCanvasTexture(256)
});
var mesh = new THREE.Mesh(sphereGeom, material);
var mesh1 = mesh.clone()
mesh1.material = mesh.material.clone()
mesh1.material.transparent = true;
mesh1.material.opacity = 0.5;
mesh1.material.map = randomCanvasTexture(256)
scene.add(mesh);
scene.add(mesh1);
renderer.setClearColor(0xdddddd, 1);
(function animate() {
mesh1.material.opacity = (Math.sin(performance.now() * 0.001) + 1) * 0.5
requestAnimationFrame(animate);
controls.update();
renderer.render(scene, camera);
})();
<script src="https://threejs.org/build/three.min.js"></script>
<script src="https://cdn.rawgit.com/mrdoob/three.js/master/examples/js/controls/OrbitControls.js"></script>
Without gunning for any optimizations, one could try something like this:
textures.forEach( tex=>{
const s = mySphere.clone()
s.material = s.material.clone()
tex.offset.copy(someOffset)
tex.repeat.copy(someRepeat)
tex.wrapS = tex.wrapT = THREE.ClampToEdgeWrapping // or something like that
s.material.map = tex
s.material.transparent = true
scene.add(s)
})
The idea is to just draw the same sphere over and over, but masked with different offsets. It might not work with just the .map but it might work with alphaMap which is either all black or all white.

Incrementally display three.js TubeGeometry

I am able to display a THREE.TubeGeometry figure as follows
Code below, link to jsbin
<html>
<body>
<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/r75/three.js"></script>
<script>
// global variables
var renderer;
var scene;
var camera;
var geometry;
var control;
var count = 0;
var animationTracker;
init();
drawSpline();
function init()
{
// create a scene, that will hold all our elements such as objects, cameras and lights.
scene = new THREE.Scene();
// create a camera, which defines where we're looking at.
camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 0.1, 1000);
// create a render, sets the background color and the size
renderer = new THREE.WebGLRenderer();
renderer.setClearColor('lightgray', 1.0);
renderer.setSize(window.innerWidth, window.innerHeight);
// position and point the camera to the center of the scene
camera.position.x = 0;
camera.position.y = 40;
camera.position.z = 40;
camera.lookAt(scene.position);
// add the output of the renderer to the html element
document.body.appendChild(renderer.domElement);
}
function drawSpline(numPoints)
{
var numPoints = 100;
// var start = new THREE.Vector3(-5, 0, 20);
var start = new THREE.Vector3(-5, 0, 20);
var middle = new THREE.Vector3(0, 35, 0);
var end = new THREE.Vector3(5, 0, -20);
var curveQuad = new THREE.QuadraticBezierCurve3(start, middle, end);
var tube = new THREE.TubeGeometry(curveQuad, numPoints, 0.5, 20, false);
var mesh = new THREE.Mesh(tube, new THREE.MeshNormalMaterial({
opacity: 0.9,
transparent: true
}));
scene.add(mesh);
renderer.render(scene, camera);
}
</script>
</body>
</html>
However, I would like to display incrementally, as in, like an arc that is loading, such that it starts as the start point, draws incrementally and finally looks the below arc upon completion.
I have been putting in some effort, and was able to do this by storing all the points/coordinates covered by the arc, and drawing lines between the consecutive coordinates, such that I get the 'arc loading incrementally' feel. However, is there a better way to achieve this? This is the link to jsbin
Adding the code here as well
<!DOCTYPE html>
<html>
<head>
<title>Incremental Spline Curve</title>
<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/r75/three.js"></script>
<style>
body {
margin: 0;
overflow: hidden;
}
</style>
</head>
<script>
// global variables
var renderer;
var scene;
var camera;
var splineGeometry;
var control;
var count = 0;
var animationTracker;
// var sphereCamera;
var sphere;
var light;
function init() {
// create a scene, that will hold all our elements such as objects, cameras and lights.
scene = new THREE.Scene();
// create a camera, which defines where we're looking at.
camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 0.1, 1000);
// create a render, sets the background color and the size
renderer = new THREE.WebGLRenderer();
// renderer.setClearColor(0x000000, 1.0);
renderer.setClearColor( 0xffffff, 1 );
renderer.setSize(window.innerWidth, window.innerHeight);
// position and point the camera to the center of the scene
camera.position.x = 0;
camera.position.y = 40;
camera.position.z = 40;
camera.lookAt(scene.position);
// add the output of the renderer to the html element
document.body.appendChild(renderer.domElement);
// //init for sphere
// sphereCamera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 1, 1000);
// sphereCamera.position.y = -400;
// sphereCamera.position.z = 400;
// sphereCamera.rotation.x = .70;
sphere = new THREE.Mesh(new THREE.SphereGeometry(0.8,31,31), new THREE.MeshLambertMaterial({
color: 'yellow',
}));
light = new THREE.DirectionalLight('white', 1);
// light.position.set(0,-400,400).normalize();
light.position.set(0,10,10).normalize();
//get points covered by Spline
getSplineData();
}
//save points in geometry.vertices
function getSplineData() {
var curve = new THREE.CubicBezierCurve3(
new THREE.Vector3( -5, 0, 10 ),
new THREE.Vector3(0, 20, 0 ),
new THREE.Vector3(0, 20, 0 ),
new THREE.Vector3( 2, 0, -25 )
);
splineGeometry = new THREE.Geometry();
splineGeometry.vertices = curve.getPoints( 50 );
animate();
}
//scheduler loop
function animate() {
if(count == 50)
{
cancelAnimationFrame(animationTracker);
return;
}
//add line to the scene
drawLine();
renderer.render(scene, camera);
// renderer.render(scene, sphereCamera);
count += 1;
// camera.position.z -= 0.25;
// camera.position.y -= 0.25;
animationTracker = requestAnimationFrame(animate);
}
function drawLine() {
var lineGeometry = new THREE.Geometry();
var lineMaterial = new THREE.LineBasicMaterial({
color: 0x0000ff
});
console.log(splineGeometry.vertices[count]);
console.log(splineGeometry.vertices[count+1]);
lineGeometry.vertices.push(
splineGeometry.vertices[count],
splineGeometry.vertices[count+1]
);
var line = new THREE.Line( lineGeometry, lineMaterial );
scene.add( line );
}
// calls the init function when the window is done loading.
window.onload = init;
</script>
<body>
</body>
</html>
Drawback : The drawback of doing it the above way is that, end of the day, I'm drawing a line between consecutive points, and so I lose out on a lot of the effects possible in TubeGeometry such as, thickness, transparency etc.
Please suggest me an alternative way to get a smooth incremental load for the TubeGeometry.
THREE.TubeGeometry returns a THREE.BufferGeometry.
With THREE.BufferGeometry, you have access to a property drawRange that you can set to animate the drawing of the mesh:
let nEnd = 0, nMax, nStep = 90; // 30 faces * 3 vertices/face
...
const geometry = new THREE.TubeGeometry( path, pathSegments, tubeRadius, radiusSegments, closed );
nMax = geometry.attributes.position.count;
...
function animate() {
requestAnimationFrame( animate );
nEnd = ( nEnd + nStep ) % nMax;
mesh.geometry.setDrawRange( 0, nEnd );
renderer.render( scene, camera );
}
EDIT: For another approach, see this SO answer.
three.js r.144
Normally you would be able to use the method .getPointAt() to "get a vector for point at relative position in curve according to arc length" to get a point at a certain percentage of the length of the curve.
So normally if you want to draw 70% of the curve and a full curve is drawn in 100 segments. Then you could do:
var percentage = 70;
var curvePath = new THREE.CurvePath();
var end, start = curveQuad.getPointAt( 0 );
for(var i = 1; i < percentage; i++){
end = curveQuad.getPointAt( percentage / 100 );
lineCurve = new THREE.LineCurve( start, end );
curvePath.add( lineCurve );
start = end;
}
But I think this is not working for your curveQuad since the getPointAt method is not implemented for this type. A work around is to get a 100 points for your curve in an array like this:
points = curve.getPoints(100);
And then you can do almost the same:
var percentage = 70;
var curvePath = new THREE.CurvePath();
var end, start = points[ 0 ];
for(var i = 1; i < percentage; i++){
end = points[ percentage ]
lineCurve = new THREE.LineCurve( start, end );
curvePath.add( lineCurve );
start = end;
}
now your curvePath holds the line segments you want to use for drawing the tube:
// draw the geometry
var radius = 5, radiusSegments = 8, closed = false;
var geometry = new THREE.TubeGeometry(curvePath, percentage, radius, radiusSegments, closed);
Here a fiddle with a demonstration on how to use this dynamically
I'm not really that familiar with three.js. But I think I can be of assistance. I have two solutions for you. Both based on the same principle: build a new TubeGeometry or rebuild the current one, around a new curve.
Solution 1 (Simple):
var CurveSection = THREE.Curve.create(function(base, from, to) {
this.base = base;
this.from = from;
this.to = to;
}, function(t) {
return this.base.getPoint((1 - t) * this.from + t * this.to);
});
You define a new type of curve which just selects a segment out of a given curve. Usage:
var curve = new CurveSection(yourCurve, 0, .76); // Where .76 is your percentage
Now you can build a new tube.
Solution 2 (Mathematics!):
You are using for your arc a quadratic bezier curve, that's awesome! This curve is a parabola. You want just a segment of that parabola and that is again a parabola, just with other bounds.
What we need is a section of the bezier curve. Let's say the curve is defined by A (start), B (direction), C (end). If we want to change the start to a point D and the end to a point F we need the point E that is the direction of the curve in D and F. So the tangents to our parabola in D and F have to intersect in E. So the following code will give us the desired result:
// Calculates the instersection point of Line3 l1 and Line3 l2.
function intersection(l1, l2) {
var A = l1.start;
var P = l2.closestPointToPoint(A);
var Q = l1.closestPointToPoint(P);
var l = P.distanceToSquared(A) / Q.distanceTo(A);
var d = (new THREE.Vector3()).subVectors(Q, A);
return d.multiplyScalar(l / d.length()).add(A);
}
// Calculate the tangentVector of the bezier-curve
function tangentQuadraticBezier(bezier, t) {
var s = bezier.v0,
m = bezier.v1,
e = bezier.v2;
return new THREE.Vector3(
THREE.CurveUtils.tangentQuadraticBezier(t, s.x, m.x, e.x),
THREE.CurveUtils.tangentQuadraticBezier(t, s.y, m.y, e.y),
THREE.CurveUtils.tangentQuadraticBezier(t, s.z, m.z, e.z)
);
}
// Returns a new QuadraticBezierCurve3 with the new bounds.
function sectionInQuadraticBezier(bezier, from, to) {
var s = bezier.v0,
m = bezier.v1,
e = bezier.v2;
var ns = bezier.getPoint(from),
ne = bezier.getPoint(to);
var nm = intersection(
new THREE.Line3(ns, tangentQuadraticBezier(bezier, from).add(ns)),
new THREE.Line3(ne, tangentQuadraticBezier(bezier, to).add(ne))
);
return new THREE.QuadraticBezierCurve3(ns, nm, ne);
}
This is a very mathematical way, but if you should need the special properties of a Bezier curve, this is the way to go.
Note: The first solution is the simplest. I am not familiar with Three.js so I wouldn't know what the most efficient way to implement the animation is. Three.js doesn't seem to use the special properties of a bezier curve so maybe solution 2 isn't that useful.
I hope you have gotten something useful out of this.

three.js showing 3d objects in same perspective

I am new to three.js,
what I am trying to achieve is ti have multiple cubes with same perspective
var g = new THREE.CubeGeometry(200, 200, 200, 1, 1, 1);
cube1 = new THREE.Mesh(g, new THREE.MeshFaceMaterial(materials));
cube1.position.set(0,0,0);
cube2 = new THREE.Mesh(g, new THREE.MeshFaceMaterial(materials));
cube2.position.set(300,0,0);
This will give me x align cubes but cube2 is rotated slightly!
Advice on what to look for would be really helpful, Thanks!
Use orthographic camera instead of perspective camera. Your camera initializiation will look something like this:
var camera = new THREE.OrthographicCamera( width / - 2, width / 2, height / 2, height / - 2, near, far );
where width and length are dimensions of canvas. Near and far define maximum and minimum distance from the camera (objects not within this range will not be rendered)
with orthographic camera boxes of same size and rotation will appear exactly same no matter of their position.
Create a function that creates cubes and then call it in a loop. Not tested but something like this should give you the desired result:
// Function to create cubes
function create_cube(x,y,z,rx,ry,rz,color) {
var geometry, material;
geometry = new THREE.CubeGeometry(5,5,5);
material = new THREE.MeshLambertMaterial({color: color});
cube = new THREE.Mesh(geometry, material);
cube.position.x += x;
cube.position.y += y;
cube.position.z += z;
cube.rotation.x += rx;
cube.rotation.y += ry;
cube.rotation.z += rz;
cube.castShadow = true;
return cube;
}
// Create 10 cubes
var n=10;
for (var i = 0; i < n; i++) {
cube = create_cube(10*i,10*i,10*i,i,i,i,0xffffff);
scene.add(cube)
}
You can use the value of i to control how each successive cube differs from the last.

My WebGL animation is slow despite requestAnimationFrame()

I'm trying to create webgl animation for my website background, inspired by "threejs - Cloud exemple" (http://mrdoob.com/lab/javascript/webgl/clouds/). On my computer it seems rather well... But for some PC it's very slow.
Is there a way to further optimize my code, and detect if the graphics card does not support webgl ?
My animation (in background) : http://wabeo.fr/?theme=auriga-7
My code :
var container = document.getElementById('container');
var wi = window.innerWidth;
var he = window.innerHeight;
var renderer = new THREE.WebGLRenderer({
antialias: true
});
var scene = new THREE.Scene();
var camera = new THREE.PerspectiveCamera(75,wi/he,1,10000);
var distance = 500;
var geometry2 = new THREE.Geometry();
renderer.setSize(wi ,he);
container.appendChild(renderer.domElement);
scene.add(camera);
var texture = THREE.ImageUtils.loadTexture( '/wp-content/themes/auriga-7/i/cloud.png' );
texture.minFilter = THREE.LinearFilter;
texture.magFilter = THREE.LinearFilter;
var m = new THREE.MeshBasicMaterial( {color:0x000000} );
var material = new THREE.MeshBasicMaterial( { map: texture,transparent: true} );
var plane = new THREE.PlaneGeometry( 400,400,4,4 );
for ( ix = 0; ix <45; ix++ ) {
item = new THREE.Mesh( plane, m );
item.position.x = ((Math.random()-0.5)*(Math.random() * wi/2) /4)*Math.random()*10;
item.position.y = ((Math.random()-0.5)*(Math.random() * he/2) /4)*Math.random()*10;
item.position.z = ix*10-50;
item.rotation.z = Math.random() *250;
item.scale.x = item.scale.y = Math.random() * Math.random() * 2 + 0.5;
THREE.GeometryUtils.merge(geometry2,item);
}
mesh = new THREE.Mesh( geometry2, material );
scene.add(mesh);
camera.position.z = distance;
camera.lookAt(scene.position);
renderer.sortObjects = false;
// create a point light
var pointLight =
new THREE.PointLight(0xFFFFFF);
// set its position
pointLight.position.x = 10;
pointLight.position.y = 50;
pointLight.position.z = 130;
// add to the scene
scene.add(pointLight);
requestAnimationFrame(wanarender);
document.addEventListener('mousemove',onMouseMove, false);
window.addEventListener('resize',onResizeMyFuckinBrowser,false);
function onMouseMove(event){
var mouseX = event.clientX - wi/2;
var mouseY = event.clientY - he/2;
camera.position.x = (mouseX - camera.position.x) * 0.02;
camera.position.y = (-mouseY - camera.position.y) * 0.02;
camera.position.z = distance;
camera.lookAt(scene.position);
}
function onResizeMyFuckinBrowser(){
var wi = window.innerWidth;
var he = window.innerHeight;
renderer.setSize(wi ,he);
}
function wanarender(){
requestAnimationFrame(wanarender);
renderer.render(scene, camera);
}
Thanks for your help :-)
Just looking quickly at the Mr Doob code, I notice a couple of optimisations that might help you. If you inspect Mr Doob's example, you can see that his cloud texture is a 256 x 256 px image, while yours is 800 x 800. There are two things to consider here:
Firstly, try to use powers of 2 for your texture sizes, ie 256, 512, 1024... This is because the graphics card is optimised for textures with these dimensions.
Secondly, 800 x 800 is probably much bigger than you really need, as the Mr Doob demo demonstrates. Most of the time, your texture is being scaled down to half the size or less.
Another thing that stands out in the Mr Doob demo is that he is using mipmaps. Mipmaps are when the graphics card pre-caches multiple versions of the texture at different scales, and uses the closest one to the current level at any given time. This makes the texture scaling more efficient, so turning them on might speed things up for you a little.
Your Code:
texture.minFilter = THREE.LinearFilter;
texture.magFilter = THREE.LinearFilter;
Mr Doob's Code:
texture.magFilter = THREE.LinearMipMapLinearFilter;
texture.minFilter = THREE.LinearMipMapLinearFilter;
Regarding detection of WebGL, See this Stack Overflow answer for information:
Three.js detect webgl support and fallback to regular canvas
I'm new to Three.jS myself but it is quite problematic to optimise your code. Few things I learned. Render before you append element if you don't like the flash of black.
keep you geometry and textures simple. The more complicated the shape, and the more images used as textures, the slower it gets.
I'm sure there's a way to optimise the graphics, but I don't know it yet. Start by trying to solve that problem.

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