phaser/filters/BinarySerpents.js
2014-03-25 14:56:04 -07:00

96 lines
3.1 KiB
JavaScript

/**
* Original shader by Trisomie21 (https://www.shadertoy.com/view/MslGRH)
* Tweaked, uniforms added and converted to Phaser/PIXI by Richard Davey
*/
Phaser.Filter.BinarySerpents = function (game) {
Phaser.Filter.call(this, game);
this.uniforms.march = { type: '1i', value: 100 };
this.uniforms.maxDistance = { type: '1f', value: 5.0 };
this.uniforms.fog = { type: '1f', value: 5.0 };
this.fragmentSrc = [
"precision mediump float;",
"uniform vec3 resolution;",
"uniform float time;",
"uniform int march;",
"uniform float maxDistance;",
"uniform float fog;",
"// With tweaks by PauloFalcao and Richard Davey",
"float Texture3D(vec3 n, float res) {",
"n = floor(n*res+.5);",
"return fract(sin((n.x+n.y*1e5+n.z*1e7)*1e-4)*1e5);",
"}",
"float map( vec3 p ) {",
"p.x+=sin(p.z*4.0+time*4.0)*0.1*cos(time*0.1);",
"p = mod(p,vec3(1.0, 1.0, 1.0))-0.5;",
"return length(p.xy)-.1;",
"}",
"void main( void )",
"{",
"vec2 pos = (gl_FragCoord.xy*2.0 - resolution.xy) / resolution.y;",
"vec3 camPos = vec3(cos(time*0.3), sin(time*0.3), 1.5);",
"vec3 camTarget = vec3(0.0, 0.0, 0.0);",
"vec3 camDir = normalize(camTarget-camPos);",
"vec3 camUp = normalize(vec3(0.0, 1.0, 0.0));",
"vec3 camSide = cross(camDir, camUp);",
"float focus = 2.0;",
"vec3 rayDir = normalize(camSide*pos.x + camUp*pos.y + camDir*focus);",
"vec3 ray = camPos;",
"float d = 0.0, total_d = 0.0;",
"const int MAX_MARCH = 100;",
"float c = 1.0;",
"for (int i=0; i < MAX_MARCH; ++i) {",
"if (i < march) {",
"d = map(ray);",
"total_d += d;",
"ray += rayDir * d;",
"if(abs(d)<0.001) { break; }",
"if(total_d>maxDistance) { c = 0.; total_d=maxDistance; break; }",
"}",
"}",
"vec4 result = vec4( vec3(c*.4 , c*.6, c) * (fog - total_d) / fog, 1.0 );",
"ray.z -= 5.+time*.5;",
"float r = Texture3D(ray, 33.);",
"gl_FragColor = result * (step(r, .3) + r * .2 + .1);",
"}"
];
};
Phaser.Filter.BinarySerpents.prototype = Object.create(Phaser.Filter.prototype);
Phaser.Filter.BinarySerpents.prototype.constructor = Phaser.Filter.BinarySerpents;
Phaser.Filter.BinarySerpents.prototype.init = function (width, height, march, maxDistance) {
if (typeof march === 'undefined') { march = 100; }
if (typeof maxDistance === 'undefined') { maxDistance = 5.0; }
this.setResolution(width, height);
this.uniforms.march.value = march;
this.uniforms.maxDistance.value = maxDistance;
}
Object.defineProperty(Phaser.Filter.BinarySerpents.prototype, 'fog', {
get: function() {
return this.uniforms.fog.value;
},
set: function(value) {
this.uniforms.fog.value = value;
}
});