| terrainSource | A function that returns the Texture data to collect from each Terrain. |
| defaultColor | The default color for sourceRenderTexture. |
| blitMaterial | The material used to copy the data. If null, the default blit material is used. |
| blitPass | The material pass used to copy the data. |
| beforeBlit | An optional action to call before copying from each Terrain. The default is null. |
| afterBlit | An optional action to call after copying from each Terrain. The default is null. |
Gathers user-specified Texture data into sourceRenderTexture.
This function collects Texture data from all Terrain tiles in the PaintContext, and merges that data into sourceRenderTexture.
The terrainSource function specifies what data to collect from each Terrain.
Gather assumes that the Texture data, which terrainSource returns, is mapped over the Terrain tile in a manner similar to the Heightmap and Alphamaps.
First, the function clears sourceRenderTexture to defaultColor.
Then, it uses the following steps to gather each Terrain in the PaintContext:
1) Calls terrainSource to retrieve the Texture.
2) Calls beforeBlit.
3) Uses blitMaterial and blitPass to copy The Texture into sourceRenderTexture.
4) Calls afterBlit.
Additional resources: PaintContext, PaintContext.Scatter.