(Read Only) RenderTexture that an edit operation writes to modify the data.
This RenderTexture stores the modified data represented by a PaintContext.
A terrain tool will typically read from sourceRenderTexture, modify the data, and write to destinationRenderTexture.
The Scatter functions (PaintContext.ScatterHeightmap or PaintContext.ScatterAlphamap) read from destinationRenderTexture to distribute the modified data back to the source Terrain tiles.
destinationRenderTexture is created by PaintContext.CreateRenderTargets, with size and format matching sourceRenderTexture.
Additional resources: PaintContext, PaintContext.sourceRenderTexture.