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davidedc/webgl_lines_colors.html

Created April 8, 2012 15:40
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Example for issue of blend losing the background transparency
Raw
webgl_lines_colors.html
<!doctype html>
<html lang="en">
<head>
<title>three.js webgl - lines - cubes - colors</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
<style>
body {
background-color: #FF0000;
margin: 0px;
overflow: hidden;
}
a {
color:#0078ff;
}
#info {
position: absolute;
top: 10px; width: 100%;
color: #ffffff;
padding: 5px;
font-family: Monospace;
font-size: 13px;
text-align: center;
z-index:100;
}
a {
color: orange;
text-decoration: none;
}
a:hover {
color: #0080ff;
}
</style>
</head>
<body>
<div id="info">
<a href="http://github.com/mrdoob/three.js" target="_blank">three.js</a> - color lines WebGL demo
[<a href="http://en.wikipedia.org/wiki/Hilbert_curve">Hilbert curve</a> thanks to <a href="http://www.openprocessing.org/visuals/?visualID=15599">Thomas Diewald</a>]
</div>
<script src="../build/Three.js"></script>
<script src="js/ShaderExtras.js"></script>
<script src="js/postprocessing/EffectComposer.js"></script>
<script src="js/postprocessing/MaskPass.js"></script>
<script src="js/postprocessing/RenderPass.js"></script>
<script src="js/postprocessing/ShaderPass.js"></script>
<script src="js/postprocessing/BloomPass.js"></script>
<script src="js/postprocessing/SavePass.js"></script>
<script src="js/Detector.js"></script>
<script src="js/Stats.js"></script>
<script>
if ( ! Detector.webgl ) Detector.addGetWebGLMessage();
var mouseX = 0, mouseY = 0,
windowHalfX = window.innerWidth / 2,
windowHalfY = window.innerHeight / 2,
camera, scene, renderer, material, composer;
init();
animate();
function init() {
var i, container;
container = document.createElement( 'div' );
document.body.appendChild( container );
scene = new THREE.Scene();
camera = new THREE.PerspectiveCamera( 33, window.innerWidth / window.innerHeight, 1, 10000 );
camera.position.z = 700;
scene.add( camera );
renderer = new THREE.WebGLRenderer( { clearColor: 0x000000, clearAlpha: 0, antialias: true } );
renderer.setSize( window.innerWidth, window.innerHeight );
renderer.autoClear = false;
container.appendChild( renderer.domElement );
var geometry = new THREE.Geometry(),
geometry2 = new THREE.Geometry(),
geometry3 = new THREE.Geometry(),
points = hilbert3D( new THREE.Vector3( 0,0,0 ), 200.0, 2, 0, 1, 2, 3, 4, 5, 6, 7 ),
colors = [], colors2 = [], colors3 = [];
for ( i = 0; i < points.length; i ++ ) {
geometry.vertices.push( new THREE.Vertex( points[ i ] ) );
colors[ i ] = new THREE.Color( 0xffffff );
colors[ i ].setHSV( 0.6, ( 200 + points[ i ].x ) / 400, 1.0 );
colors2[ i ] = new THREE.Color( 0xffffff );
colors2[ i ].setHSV( 0.3, 1.0, ( 200 + points[ i ].x ) / 400 );
colors3[ i ] = new THREE.Color( 0xffffff );
colors3[ i ].setHSV( i / points.length, 1.0, 1.0 );
}
geometry2.vertices = geometry3.vertices = geometry.vertices;
geometry.colors = colors;
geometry2.colors = colors2;
geometry3.colors = colors3;
// lines
material = new THREE.LineBasicMaterial( { color: 0xffffff, opacity: 1, linewidth: 3 } );
var line, p, scale = 0.3, d = 225,
parameters = [ [ material, scale*1.5, [-d,0,0], geometry ],
[ material, scale*1.5, [0,0,0], geometry2 ],
[ material, scale*1.5, [d,0,0], geometry3 ] ];
material.vertexColors = true;
for ( i = 0; i < parameters.length; ++i ) {
p = parameters[ i ];
line = new THREE.Line( p[ 3 ], p[ 0 ] );
line.scale.x = line.scale.y = line.scale.z = p[ 1 ];
line.position.x = p[ 2 ][ 0 ];
line.position.y = p[ 2 ][ 1 ];
line.position.z = p[ 2 ][ 2 ];
scene.add( line );
}
//
stats = new Stats();
stats.domElement.style.position = 'absolute';
stats.domElement.style.top = '0px';
//container.appendChild( stats.domElement );
//
renderTargetParameters = { format: THREE.RGBAFormat, stencilBuffer: true };
renderTarget = new THREE.WebGLRenderTarget( window.innerWidth, window.innerHeight, renderTargetParameters );
effectSaveTarget = new THREE.SavePass( new THREE.WebGLRenderTarget( window.innerWidth, window.innerHeight, renderTargetParameters ) );
effectSaveTarget.clear = false;
effectBlend = new THREE.ShaderPass( THREE.ShaderExtras[ "blend" ], "tDiffuse1" );
screenPass = new THREE.ShaderPass( THREE.ShaderExtras[ "screen" ] );
// motion blur
effectBlend.uniforms[ 'tDiffuse2' ].texture = effectSaveTarget.renderTarget;
effectBlend.uniforms[ 'mixRatio' ].value = 0.25;
var renderModel = new THREE.RenderPass( scene, camera );
composer = new THREE.EffectComposer( renderer, renderTarget );
composer.addPass( renderModel );
// if I uncomment these two, the motion blur kicks-in but I lose the
// transparent background.
composer.addPass( effectBlend ); //***
composer.addPass( effectSaveTarget ); //***
composer.addPass( screenPass );
screenPass.renderToScreen = true;
}
// port of Processing Java code by Thomas Diewald
// http://www.openprocessing.org/visuals/?visualID=15599
function hilbert3D( center, side, iterations, v0, v1, v2, v3, v4, v5, v6, v7 ) {
var half = side / 2,
vec_s = [
new THREE.Vector3( center.x - half, center.y + half, center.z - half ),
new THREE.Vector3( center.x - half, center.y + half, center.z + half ),
new THREE.Vector3( center.x - half, center.y - half, center.z + half ),
new THREE.Vector3( center.x - half, center.y - half, center.z - half ),
new THREE.Vector3( center.x + half, center.y - half, center.z - half ),
new THREE.Vector3( center.x + half, center.y - half, center.z + half ),
new THREE.Vector3( center.x + half, center.y + half, center.z + half ),
new THREE.Vector3( center.x + half, center.y + half, center.z - half )
],
vec = [ vec_s[ v0 ], vec_s[ v1 ], vec_s[ v2 ], vec_s[ v3 ], vec_s[ v4 ], vec_s[ v5 ], vec_s[ v6 ], vec_s[ v7 ] ];
if( --iterations >= 0 ) {
var tmp = [];
Array.prototype.push.apply( tmp, hilbert3D ( vec[ 0 ], half, iterations, v0, v3, v4, v7, v6, v5, v2, v1 ) );
Array.prototype.push.apply( tmp, hilbert3D ( vec[ 1 ], half, iterations, v0, v7, v6, v1, v2, v5, v4, v3 ) );
Array.prototype.push.apply( tmp, hilbert3D ( vec[ 2 ], half, iterations, v0, v7, v6, v1, v2, v5, v4, v3 ) );
Array.prototype.push.apply( tmp, hilbert3D ( vec[ 3 ], half, iterations, v2, v3, v0, v1, v6, v7, v4, v5 ) );
Array.prototype.push.apply( tmp, hilbert3D ( vec[ 4 ], half, iterations, v2, v3, v0, v1, v6, v7, v4, v5 ) );
Array.prototype.push.apply( tmp, hilbert3D ( vec[ 5 ], half, iterations, v4, v3, v2, v5, v6, v1, v0, v7 ) );
Array.prototype.push.apply( tmp, hilbert3D ( vec[ 6 ], half, iterations, v4, v3, v2, v5, v6, v1, v0, v7 ) );
Array.prototype.push.apply( tmp, hilbert3D ( vec[ 7 ], half, iterations, v6, v5, v2, v1, v0, v3, v4, v7 ) );
return tmp;
}
return vec;
}
//
function onDocumentMouseMove( event ) {
}
function onDocumentTouchStart( event ) {
}
function onDocumentTouchMove( event ) {
}
//
function animate() {
requestAnimationFrame( animate );
render();
stats.update();
}
function render() {
camera.position.x += ( mouseX - camera.position.x ) * .05;
camera.position.y += ( - mouseY + 200 - camera.position.y ) * .05;
camera.lookAt( scene.position );
var time = Date.now() * 0.005;
for( var i = 0; i < scene.objects.length; i ++ ) {
scene.objects[ i ].rotation.y = time * ( i % 2 ? 1 : -1 );
}
renderer.clear();
//renderer.render(scene, camera);
composer.render();
}
</script>
</body>
</html>
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