Method InitTextureAttribs

Hydrogent/src/HnMaterial.cpp:242–304

}

void HnMaterial::InitTextureAttribs(HnTextureRegistry& TexRegistry, const USD_Renderer& UsdRenderer, const TexNameToCoordSetMapType& TexNameToCoordSetMap)
{
    GLTF::MaterialBuilder MatBuilder{m_MaterialData};

    auto SetTextureParams = [&](const pxr::TfToken& Name, Uint32 Idx) {
        GLTF::Material::TextureShaderAttribs& TexAttribs = MatBuilder.GetTextureAttrib(Idx);

        auto coord_it         = TexNameToCoordSetMap.find(Name);
        TexAttribs.UVSelector = coord_it != TexNameToCoordSetMap.end() ?
            static_cast<float>(coord_it->second) :
            0;

        TexAttribs.UBias              = 0;
        TexAttribs.VBias              = 0;
        TexAttribs.UVScaleAndRotation = float2x2::Identity();

        auto tex_it = m_Textures.find(Name);
        if (tex_it != m_Textures.end())
        {
            if (const HnMaterialParameter* Param = m_Network.GetParameter(HnMaterialParameter::ParamType::Transform2d, Name))
            {
                float2x2 UVScaleAndRotation = float2x2::Scale(Param->Transform2d.Scale[0], Param->Transform2d.Scale[1]);
                float    Rotation           = Param->Transform2d.Rotation;
                if (Rotation != 0)
                {
                    UVScaleAndRotation *= float2x2::Rotation(DegToRad(Rotation));
                }

                TexAttribs.UBias = Param->Transform2d.Translation[0];
                TexAttribs.VBias = Param->Transform2d.Translation[1];

                TexAttribs.UVScaleAndRotation = UVScaleAndRotation;
            }
        }
        else
        {
            tex_it = m_Textures.emplace(Name, GetDefaultTexture(TexRegistry, Name)).first;
        }

        if (ITextureAtlasSuballocation* pAtlasSuballocation = tex_it->second->pAtlasSuballocation)
        {
            TexAttribs.TextureSlice        = static_cast<float>(pAtlasSuballocation->GetSlice());
            TexAttribs.AtlasUVScaleAndBias = pAtlasSuballocation->GetUVScaleBias();
        }
        else
        {
            TexAttribs.TextureSlice        = static_cast<float>(tex_it->second->TextureId);
            TexAttribs.AtlasUVScaleAndBias = float4{1, 1, 0, 0};
        }
    };

    const auto& TexAttribIndices = UsdRenderer.GetSettings().TextureAttribIndices;
    // clang-format off
    SetTextureParams(HnTokens->diffuseColor,  TexAttribIndices[PBR_Renderer::TEXTURE_ATTRIB_ID_BASE_COLOR]);
    SetTextureParams(HnTokens->normal,        TexAttribIndices[PBR_Renderer::TEXTURE_ATTRIB_ID_NORMAL]);
    SetTextureParams(HnTokens->metallic,      TexAttribIndices[PBR_Renderer::TEXTURE_ATTRIB_ID_METALLIC]);
    SetTextureParams(HnTokens->roughness,     TexAttribIndices[PBR_Renderer::TEXTURE_ATTRIB_ID_ROUGHNESS]);
    SetTextureParams(HnTokens->occlusion,     TexAttribIndices[PBR_Renderer::TEXTURE_ATTRIB_ID_OCCLUSION]);