Adding the shader examples

java/examples/Topics/Shaders/ToonShading/ToonShading.pde

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+/**
+ * Toon Shading.
+ * 
+ * Example showing the use of a custom lighting shader in order  
+ * to apply a "toon" effect on the scene. Based on the glsl tutorial 
+ * from lighthouse 3D:
+ * http://www.lighthouse3d.com/tutorials/glsl-tutorial/toon-shader-version-ii/
+ */
+ 
+PShader toon;
+boolean shaderEnabled = true;  
+
+void setup() {
+  size(640, 360, P3D);
+  noStroke();
+  fill(204);
+  toon = loadShader("ToonFrag.glsl", "ToonVert.glsl");
+}
+
+void draw() {
+  if (shaderEnabled == true) {
+    shader(toon);
+  }
+
+  noStroke(); 
+  background(0); 
+  float dirY = (mouseY / float(height) - 0.5) * 2;
+  float dirX = (mouseX / float(width) - 0.5) * 2;
+  directionalLight(204, 204, 204, -dirX, -dirY, -1);
+  translate(width/2, height/2);
+  sphere(120);
+}  
+
+void mousePressed() {
+  if (shaderEnabled) {
+    shaderEnabled = false;
+    resetShader();
+  } 
+  else {
+    shaderEnabled = true;
+  }
+}
+

java/examples/Topics/Shaders/ToonShading/data/ToonFrag.glsl

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+varying vec3 vertNormal;
+varying vec3 vertLightDir;
+
+void main() {  
+  float intensity;
+  vec4 color;
+  intensity = max(0.0, dot(vertLightDir, vertNormal));
+
+  if (intensity > 0.95) {
+    color = vec4(1.0, 0.5, 0.5, 1.0);
+  } else if (intensity > 0.5) {
+    color = vec4(0.6, 0.3, 0.3, 1.0);
+  } else if (intensity > 0.25) {
+    color = vec4(0.4, 0.2, 0.2, 1.0);
+  } else {
+    color = vec4(0.2, 0.1, 0.1, 1.0);
+  }
+
+  gl_FragColor = color;  
+}

java/examples/Topics/Shaders/ToonShading/data/ToonVert.glsl

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+// Toon shader using per-pixel lighting. Based on the glsl 
+// tutorial from lighthouse 3D:
+// http://www.lighthouse3d.com/tutorials/glsl-tutorial/toon-shader-version-ii/
+
+uniform mat4 modelviewMatrix;
+uniform mat4 projmodelviewMatrix;
+uniform mat3 normalMatrix;
+
+uniform vec3 lightNormal[8];
+
+attribute vec4 inVertex;
+attribute vec3 inNormal;
+
+varying vec3 vertNormal;
+varying vec3 vertLightDir;
+
+void main() {
+  // Vertex in clip coordinates
+  gl_Position = projmodelviewMatrix * inVertex;
+  
+  // Normal vector in eye coordinates is passed
+  // to the fragment shader
+  vertNormal = normalize(normalMatrix * inNormal);
+  
+  // Assuming that there is only one directional light.
+  // Its normal vector is passed to the fragment shader
+  // in order to perform per-pixel lighting calculation.  
+  vertLightDir = -lightNormal[0]; 
+}