anchor.diff:    bool result = gl.getShaderParameter(shader, GL_COMPILE_STATUS);
     if (result != null && result == false) {
       String error = gl.getShaderInfoLog(shader);
  -    LogInfo("Compilation failed:");
  -    LogInfo(_AddLineNumbers(text));
  -    LogInfo("Failure:");
  -    LogInfo(error);
  +    LogError("Compilation failed:");
  +    LogError(_AddLineNumbers(text));
  +    LogError("Failure:");
  +    LogError(error);
       throw error;
     }
     return shader;
  
positive.code:       "antialias": antialiasing,
        "premultipliedAlpha": true,
        "preserveDrawingBuffer": preserveDrawingBuffer,
      };
  
      _gl = _canvas.getContext("webgl2", attributes);
  
negative.code:       throw new Exception(NO_WEBGL_MESSAGE);
      }
  
  
      dynamic actual = _gl.getContextAttributes();
  /*
      LogInfo("alpha: ${actual.alpha}");
      LogInfo("antialias: ${actual.antialias}");
      LogInfo("depth: ${actual.depth}");
      LogInfo("stencil: ${actual.stencil}");
      LogInfo("premultipliedAlpha: ${actual.premultipliedAlpha}");
      LogInfo("preserveDrawingBuffer: ${actual.preserveDrawingBuffer}");
      LogInfo("failIfMajorPerformanceCaveat: ${actual.failIfMajorPerformanceCaveat}");
  */
      _gl.clearColor(0.0, 0.0, 0.0, 1.0);
      _gl.enable(GL_DEPTH_TEST);
      if (faceCulling) {
  