code: func (c *Context) BlendEquationSeparate(modeRGB, modeAlpha int) {
  	c.Call("blendEquationSeparate", modeRGB, modeAlpha)
  }
docs: // Controls the blending of an incoming source fragment's R, G, B, and A values
  // with a destination R, G, B, and A values as stored in the fragment's WebGLFramebuffer.