生成深度 + 法线纹理。
Will generate a screen-space depth and view space normals texture as seen from this camera.
Texture will be in RenderTextureFormat.ARGB32 format and will be set as _CameraDepthNormalsTexture
global shader property. Depth and normals will be specially encoded, see Camera Depth Texture page for details.
另请参阅：Using camera's depth textures、Camera.depthTextureMode。