These changes are needed for when we turn on REAL ...

samples/o3d-webgl/effect.js

 /*
  * Copyright 2010, Google Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 186 matching lines @@
  * @return {bool} Success.
  */
 o3d.Effect.prototype.loadShaderFromString = function(shaderString, type) {
   if (!this.program_) {
     this.program_ = this.gl.createProgram();
   }
 
   var success = true;
 
   var shader = this.gl.createShader(type);
-  this.gl.shaderSource(shader, shaderString);
+  this.gl.shaderSource(
+      shader, "#ifdef GL_ES\nprecision highp float;\n#endif\n" + shaderString);
   this.gl.compileShader(shader);
-
   if (!this.gl.getShaderParameter(shader, this.gl.COMPILE_STATUS)) {
     success = false;
     var log = this.gl.getShaderInfoLog(shader);
     this.gl.client.error_callback(
         'Shader compile failed with error log:\n' + log);
   }
 
   this.gl.attachShader(this.program_, shader);
 
   return success;
@@ skipping 399 matching lines @@
  * @type {o3d.Effect.MatrixLoadOrder}
  */
 o3d.Effect.prototype.matrix_load_order_ = o3d.Effect.ROW_MAJOR;
 
 
 /**
  * The source for the shaders on this Effect.
  * @type {string}
  */
 o3d.Effect.prototype.source_ = '';