o3d-webgl: Adjusting Sampler to throw an error if client attempts to use BORD...

samples/o3d-webgl-samples/texturesamplers.html

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@@ skipping 167 matching lines @@
   //  borderColor = Float4(0, 0, 0, 0)
   //  maxAnisotropy = 1
 
   // Rotates quad and uses anisotropic filtering.
   transforms[1].rotateZ(-Math.PI / 2.5);
   samplers[1].addressModeU = g_o3d.Sampler.WRAP;
   samplers[1].addressModeV = g_o3d.Sampler.WRAP;
   samplers[1].minFilter = g_o3d.Sampler.ANISOTROPIC;
   samplers[1].maxAnisotropy = 4;
 
-  // Uses BORDER addressing mode with a red border.
-  samplers[2].addressModeU = g_o3d.Sampler.BORDER;
-  samplers[2].addressModeV = g_o3d.Sampler.BORDER;
-  samplers[2].borderColor = [1, 0, 0, 1];
+  // Note: BORDER addressing is not supported in WebGL.
+  //samplers[2].addressModeU = g_o3d.Sampler.BORDER;
+  //samplers[2].addressModeV = g_o3d.Sampler.BORDER;
+  //samplers[2].borderColor = [1, 0, 0, 1];
 
   // Uses POINT sampling for minification.
   samplers[3].addressModeU = g_o3d.Sampler.WRAP;
   samplers[3].addressModeV = g_o3d.Sampler.WRAP;
   samplers[3].minFilter = g_o3d.Sampler.POINT;
 
   // Rotates quad and uses default (linear) filtering.
   // Compare results to quad #1.
   transforms[4].rotateZ(-Math.PI / 2.5);
   samplers[4].addressModeU = g_o3d.Sampler.WRAP;
@@ skipping 61 matching lines @@
 
 /* Given the texture coordinates, our pixel shader grabs the corresponding
  * color from the texture.
  */
 void main() {
   gl_FragColor = texture2D(texSampler, texCoord);
 }
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