Add GetFirstTextureParam() to get first declared texture from shader, used to fetch the convoluted RepresentativeTexture/LightSim_DiffuseAlbedoTexture attributes without explicit declaration Allow material representative texture for VRAD be infered by the first texture parameter on shader if DiffuseAlbedoTexture is not set, allows to clean up all this material api & lets shadergraph shaders be rendered properly on vrad https://files.facepunch.com/sampavlovic/1b0611b1/aocrkIAnQN.png