anchor.diff:        "antialias": antialiasing,
         "premultipliedAlpha": true,
         "preserveDrawingBuffer": preserveDrawingBuffer,
  +      "failIfMajorPerformanceCaveat": false,
       };
   
       _gl = _canvas.getContext("webgl2", attributes);
  
positive.code:     _gl.uniform1i(location, value);
    }
  
    void uniform1fv(WEBGL.UniformLocation location, Float32List value) {
      _gl.uniform1fv(location, value);
    }
  
negative.code:   bool result = gl.getShaderParameter(shader, GL_COMPILE_STATUS);
    if (result != null && result == false) {
      String error = gl.getShaderInfoLog(shader);
      LogError("Compilation failed:");
      LogError(_AddLineNumbers(text));
      LogError("Failure:");
      LogError(error);
      throw error;
    }
    return shader;
  