webvr js meetup initial commit

node_modules/three/examples/js/shaders/EdgeShader2.js

@@ -0,0 +1,73 @@
+/**
+ * @author zz85 / https://github.com/zz85 | https://www.lab4games.net/zz85/blog
+ *
+ * Edge Detection Shader using Sobel filter
+ * Based on http://rastergrid.com/blog/2011/01/frei-chen-edge-detector
+ *
+ * aspect: vec2 of (1/width, 1/height)
+ */
+
+THREE.EdgeShader2 = {
+
+	uniforms: {
+
+		"tDiffuse": { value: null },
+		"aspect":    { value: new THREE.Vector2( 512, 512 ) }
+	},
+
+	vertexShader: [
+
+		"varying vec2 vUv;",
+
+		"void main() {",
+
+			"vUv = uv;",
+			"gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );",
+
+		"}"
+
+	].join( "\n" ),
+
+	fragmentShader: [
+
+		"uniform sampler2D tDiffuse;",
+		"varying vec2 vUv;",
+		"uniform vec2 aspect;",
+
+
+		"vec2 texel = vec2(1.0 / aspect.x, 1.0 / aspect.y);",
+
+		"mat3 G[2];",
+
+		"const mat3 g0 = mat3( 1.0, 2.0, 1.0, 0.0, 0.0, 0.0, -1.0, -2.0, -1.0 );",
+		"const mat3 g1 = mat3( 1.0, 0.0, -1.0, 2.0, 0.0, -2.0, 1.0, 0.0, -1.0 );",
+
+
+		"void main(void)",
+		"{",
+			"mat3 I;",
+			"float cnv[2];",
+			"vec3 sample;",
+
+			"G[0] = g0;",
+			"G[1] = g1;",
+
+			/* fetch the 3x3 neighbourhood and use the RGB vector's length as intensity value */
+			"for (float i=0.0; i<3.0; i++)",
+			"for (float j=0.0; j<3.0; j++) {",
+				"sample = texture2D( tDiffuse, vUv + texel * vec2(i-1.0,j-1.0) ).rgb;",
+				"I[int(i)][int(j)] = length(sample);",
+			"}",
+
+			/* calculate the convolution values for all the masks */
+			"for (int i=0; i<2; i++) {",
+				"float dp3 = dot(G[i][0], I[0]) + dot(G[i][1], I[1]) + dot(G[i][2], I[2]);",
+				"cnv[i] = dp3 * dp3; ",
+			"}",
+
+			"gl_FragColor = vec4(0.5 * sqrt(cnv[0]*cnv[0]+cnv[1]*cnv[1]));",
+		"} "
+
+	].join( "\n" )
+
+};