Doodle3D-Slicer/three.js-master/examples/js/shaders/KaleidoShader.js
2017-06-22 13:21:07 +02:00

61 lines
1.1 KiB
JavaScript
Executable File

/**
* @author felixturner / http://airtight.cc/
*
* Kaleidoscope Shader
* Radial reflection around center point
* Ported from: http://pixelshaders.com/editor/
* by Toby Schachman / http://tobyschachman.com/
*
* sides: number of reflections
* angle: initial angle in radians
*/
THREE.KaleidoShader = {
uniforms: {
"tDiffuse": { type: "t", value: null },
"sides": { type: "f", value: 6.0 },
"angle": { type: "f", value: 0.0 }
},
vertexShader: [
"varying vec2 vUv;",
"void main() {",
"vUv = uv;",
"gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );",
"}"
].join("\n"),
fragmentShader: [
"uniform sampler2D tDiffuse;",
"uniform float sides;",
"uniform float angle;",
"varying vec2 vUv;",
"void main() {",
"vec2 p = vUv - 0.5;",
"float r = length(p);",
"float a = atan(p.y, p.x) + angle;",
"float tau = 2. * 3.1416 ;",
"a = mod(a, tau/sides);",
"a = abs(a - tau/sides/2.) ;",
"p = r * vec2(cos(a), sin(a));",
"vec4 color = texture2D(tDiffuse, p + 0.5);",
"gl_FragColor = color;",
"}"
].join("\n")
};