add another filter effect to squares.html

Author: peteroupc

glutil.js

@@ -497,8 +497,8 @@ function LightSource(position, ambient, diffuse, specular) {
 * number is the W component.<ul>
 * <li>If W is 0, then X, Y, and Z specify a 3-element vector giving the direction
 * of the light; the light will shine everywhere in the given direction.
-* <li>If W is 0, then X, Y, and Z specify the position of the light in world
-* space; the light will shine brightest at the given position.</p>
+* <li>If W is 1, then X, Y, and Z specify the position of the light in world
+* space; the light will shine brightest, and in every direction, at the given position.</ul>
 * <li><code>ambient</code> - Not used in the default shader program.
 * <li><code>diffuse</code> - Diffuse color.
 * <li><code>specular</code> - Specular highlight color.

squares.html

@@ -10,6 +10,7 @@ <h1>Shader Filters</h1>
 <a href="javascript:link4()">Blur</a>,
 <a href="javascript:link5()">Pixelate</a>,
 <a href="javascript:link6()">Waterpaint</a>,
+<a href="javascript:link7()">Mirror</a>,
 <a href="javascript:linknone()">No filters</a><br>
 <a href="javascript:link1a()">Blinds</a>,
 <a href="javascript:link2a()">Platonic solids</a>
@@ -137,6 +138,14 @@ <h1>Shader Filters</h1>
 "}"].join("\n"));
 }
 
+function makeMirror(context){
+return ShaderProgram.makeEffect(context,[
+"vec4 textureEffect(sampler2D sampler, vec2 uvCoord, vec2 textureSize){",
+" vec4 color=texture2D(sampler,vec2(1.0-uvCoord.x,uvCoord.y));",
+" return color;",
+"}"].join("\n"));
+}
+
 function link1(){
  if(scene){
   if(currentFilter)currentFilter.dispose();
@@ -198,6 +207,13 @@ <h1>Shader Filters</h1>
   scene.useFilter(currentFilter);
  }
 }
+function link7(){
+ if(scene){
+  if(currentFilter)currentFilter.dispose();
+  currentFilter=makeMirror(scene);
+  scene.useFilter(currentFilter);
+ }
+}
 function linknone(){
  if(scene){
   if(currentFilter)currentFilter.dispose();