phaser/filters/Plasma.js
2014-03-25 14:56:06 -07:00

123 lines
3.2 KiB
JavaScript

/**
* Original shader by TriggerHLM (https://www.shadertoy.com/view/MdXGDH)
* Tweaked, uniforms added and converted to Phaser/PIXI by Richard Davey
*/
Phaser.Filter.Plasma = function (game) {
Phaser.Filter.call(this, game);
this.uniforms.alpha = { type: '1f', value: 1.0 };
this.uniforms.size = { type: '1f', value: 0.03 };
this.uniforms.redShift = { type: '1f', value: 0.5 };
this.uniforms.greenShift = { type: '1f', value: 0.5 };
this.uniforms.blueShift = { type: '1f', value: 0.9 };
this.fragmentSrc = [
"precision mediump float;",
"uniform float time;",
"uniform float alpha;",
"uniform float size;",
"uniform float redShift;",
"uniform float greenShift;",
"uniform float blueShift;",
"const float PI = 3.14159265;",
"float ptime = time * 0.1;",
"void main(void) {",
"float color1, color2, color;",
"color1 = (sin(dot(gl_FragCoord.xy, vec2(sin(ptime * 3.0), cos(ptime * 3.0))) * 0.02 + ptime * 3.0) + 1.0) / 2.0;",
"vec2 center = vec2(640.0 / 2.0, 360.0 / 2.0) + vec2(640.0 / 2.0 * sin(-ptime * 3.0), 360.0 / 2.0 * cos(-ptime * 3.0));",
"color2 = (cos(length(gl_FragCoord.xy - center) * size) + 1.0) / 2.0;",
"color = (color1 + color2) / 2.0;",
"float red = (cos(PI * color / redShift + ptime * 3.0) + 1.0) / 2.0;",
"float green = (sin(PI * color / greenShift + ptime * 3.0) + 1.0) / 2.0;",
"float blue = (sin(PI * color / blueShift + ptime * 3.0) + 1.0) / 2.0;",
"gl_FragColor = vec4(red, green, blue, alpha);",
"}"
];
};
Phaser.Filter.Plasma.prototype = Object.create(Phaser.Filter.prototype);
Phaser.Filter.Plasma.prototype.constructor = Phaser.Filter.Plasma;
Phaser.Filter.Plasma.prototype.init = function (width, height, alpha, size) {
this.setResolution(width, height);
if (typeof alpha !== 'undefined') {
this.uniforms.alpha.value = alpha;
}
if (typeof size !== 'undefined') {
this.uniforms.size.value = size;
}
};
Object.defineProperty(Phaser.Filter.Plasma.prototype, 'alpha', {
get: function() {
return this.uniforms.alpha.value;
},
set: function(value) {
this.uniforms.alpha.value = value;
}
});
Object.defineProperty(Phaser.Filter.Plasma.prototype, 'size', {
get: function() {
return this.uniforms.size.value;
},
set: function(value) {
this.uniforms.size.value = value;
}
});
Object.defineProperty(Phaser.Filter.Plasma.prototype, 'redShift', {
get: function() {
return this.uniforms.redShift.value;
},
set: function(value) {
this.uniforms.redShift.value = value;
}
});
Object.defineProperty(Phaser.Filter.Plasma.prototype, 'greenShift', {
get: function() {
return this.uniforms.greenShift.value;
},
set: function(value) {
this.uniforms.greenShift.value = value;
}
});
Object.defineProperty(Phaser.Filter.Plasma.prototype, 'blueShift', {
get: function() {
return this.uniforms.blueShift.value;
},
set: function(value) {
this.uniforms.blueShift.value = value;
}
});