El nivel antialiasing para la RenderTexture.
El valor anti-aliasing debe ser uno de (1, 2, 4 o 8), indicando la cantidad de muestras por pixel.
When a RenderTexture is using anti-aliasing, then any rendering into it will happen into the multi-sampled
texture, which will be "resolved" into a regular texture when switching to another render target. To the rest
of the system only this "resolved" surface is visible.