GroupRenderToTexture { children [....] outputTexture [ CompositeTexture3D {...} # renderTarget[0] CompositeTexture3D {...} # renderTarget[1] CompositeTexture3D {...} # renderTarget[2] CompositeTexture3D {...} # renderTarget[3] ] renderTarget [ "COLOR0" # renderTarget[0] "COLOR1" # renderTarget[1] "COLOR2" # renderTarget[2] "DEPTH0" # renderTarget[3] ] outputChildren [...] }