basically working

assets/js/seriously/effects/seriously.colorcube.js

@@ -0,0 +1,71 @@
+/* global define, require */
+(function (root, factory) {
+	'use strict';
+
+	if (typeof define === 'function' && define.amd) {
+		// AMD. Register as an anonymous module.
+		define(['seriously'], factory);
+	} else if (typeof exports === 'object') {
+		// Node/CommonJS
+		factory(require('seriously'));
+	} else {
+		if (!root.Seriously) {
+			root.Seriously = { plugin: function (name, opt) { this[name] = opt; } };
+		}
+		factory(root.Seriously);
+	}
+}(window, function (Seriously) {
+	'use strict';
+
+	// based on tutorial by to Gregg Tavares
+	// http://www.youtube.com/watch?v=rfQ8rKGTVlg&t=24m30s
+	// todo: find a way to not invert every single texture
+
+	Seriously.plugin('colorcube', {
+		commonShader: true,
+		shader: function (inputs, shaderSource) {
+			shaderSource.fragment = [
+				'precision mediump float;',
+
+				'uniform sampler2D source;',
+				'uniform sampler2D colorCube;',
+				'varying vec2 vTexCoord;',
+
+				'vec3 sampleAs3DTexture(sampler2D tex, vec3 coord, float size) {',
+				'	float sliceSize = 1.0 / size;', // space of 1 slice
+				'	float slicePixelSize = sliceSize / size;', // space of 1 pixel
+				'	float sliceInnerSize = slicePixelSize * (size - 1.0);', // space of size pixels
+				'	float zSlice0 = min(floor(coord.z * size), size - 1.0);',
+				'	float zSlice1 = min(zSlice0 + 1.0, size - 1.0);',
+				'	float xOffset = slicePixelSize * 0.5 + coord.x * sliceInnerSize;',
+				'	float s0 = xOffset + (zSlice0 * sliceSize);',
+				'	float s1 = xOffset + (zSlice1 * sliceSize);',
+				'	vec3 slice0Color = texture2D(tex, vec2(s0, 1.0 - coord.y)).rgb;',
+				'	vec3 slice1Color = texture2D(tex, vec2(s1, 1.0 - coord.y)).rgb;',
+				'	float zOffset = mod(coord.z * size, 1.0);',
+				'	return mix(slice0Color, slice1Color, zOffset);',
+				'}',
+
+				'void main(void) {',
+				'	vec4 originalColor = texture2D(source, vTexCoord);',
+				'	vec3 color = sampleAs3DTexture(colorCube, originalColor.rgb, 8.0);',
+				'	gl_FragColor = vec4(color, originalColor.a);',
+				'}'
+			].join('\n');
+			return shaderSource;
+		},
+		inPlace: true,
+		inputs: {
+			source: {
+				type: 'image',
+				uniform: 'source'
+			},
+			cube: {
+				type: 'image',
+				uniform: 'colorCube'
+			}
+		},
+		title: 'Color Cube',
+		description: ''
+	});
+}));