ライトマップのデータを格納しています。
A Scene can have several lightmaps stored in it, and Renderer components can use those
lightmaps. This makes it possible to use the same material on multiple objects, while
each object can refer to a different lightmap or different portion of the same lightmap.
関連項目: LightmapSettings クラス、Renderer.lightmapIndex
| lightmapColor | Lightmap storing color of incoming light. |
| lightmapDir | Lightmap storing dominant direction of incoming light. |
| shadowMask | Texture storing occlusion mask per light (ShadowMask, up to four lights). |