Merge pull request #10 from Dutch77/feature/edge-webgl-frag

edge webgl frag

src/nodes/WebGL/Edge.ts

@@ -0,0 +1,71 @@
+import WebGL from './WebGl';
+import {
+    NumberVar
+} from '../io/AbstractIOSet';
+
+const inputs = {
+    dx: {
+        type: 'Number',
+        default: 0,
+    }  as NumberVar,
+    dy: {
+        type: 'Number',
+        default: 0,
+    }  as NumberVar,
+}
+
+export default class Edge extends WebGL<typeof inputs> {
+
+    constructor() {
+        super('Edge', inputs)
+    }
+
+    get frag() {
+        return `
+        precision mediump float;
+
+        // our texture
+        uniform sampler2D u_image;
+
+        uniform vec2 u_resolution;
+        uniform vec2 u_textureSize;
+
+        // the texCoords passed in from the vertex shader.
+        varying vec2 v_texCoord;
+
+        
+        uniform vec2 delta;
+
+        void main() {
+            vec2 onePixel = vec2(1.0, 1.0) / u_textureSize;
+
+            gl_FragColor = vec4(
+                (
+                  (
+                    texture2D(u_image, v_texCoord + onePixel * vec2(0, 0)) - 
+                    texture2D(u_image, v_texCoord + onePixel * delta)
+                  ) / 2.0 + 0.5
+                ).xyz,
+                1
+            );
+        }
+        `
+    }
+
+    get dx() {
+        return this.in.dx.value;
+    }
+
+    get dy() {
+        return this.in.dy.value;
+    }
+
+    /**
+     *
+     * @param {WebGLRenderingContext} gl
+     * @param {*} program
+     */
+    _setParams(gl, program) {
+        gl.uniform2f(gl.getUniformLocation(program, "delta"), this.dx, this.dy);
+    }
+}

src/nodes/index.ts

@@ -17,6 +17,7 @@ export {default as GradientMap} from './WebGL/GradientMap';
 export {default as ColorLookupTable} from './WebGL/ColorLookupTable';
 export {default as Vignette} from './WebGL/Vignette';
 // export {default as Blur} from './WebGL/Blur';
+export {default as Edge} from './WebGL/Edge';
 // Math
 export {default as Numbers} from './Math/Numbers';
 export {default as NumberBinaryOperation} from './Math/NumberBinaryOperation';