| discardColor | Should the colour buffer be discarded? |
| discardDepth | Should the depth buffer be discarded? |
Discards the contents of the RenderTexture.
On some platforms, it can be good for performance if you indicate when the
current contents of a RenderTexture aren't needed any more. This can save
copying it from one kind of memory to another when the texture is reused.
Xbox 360 and many mobile GPUs benefit from this.
Both the colour buffer and depth buffer are discarded by default but either can be selected individually using the optional boolean parameters.