Method update

Source/Falcor/Scene/Material/MaterialSystem.cpp:448–611

    }

    Material::UpdateFlags MaterialSystem::update(bool forceUpdate)
    {
        // Some materials only determine the required number of textures during their update.
        // If the number of required textures is greated than getMaxTextureCount() reported,
        // we could run out of texture slots. This is why metadata is reupdated again,
        // after the material's update() has been called. (A typical example is UDIM, the number
        // of actually used texture slots depends on the number of files on drive)
        bool reupdateMetadata = false;

        // If materials were added/removed since last update, we update all metadata
        // and trigger re-creation of the parameter block and update of all materials.
        if (forceUpdate || mMaterialsChanged)
        {
            updateMetadata();
            updateUI();

            mpMaterialsBlock = nullptr;
            mMaterialsChanged = false;
            forceUpdate = true;
            reupdateMetadata = true;
        }

        // Update all materials.
        // Do either a full update of all materials with deferred texture loading, or an update of just the dynamic materials.
        // We track per-material update flags along with the combined update flags across all materials.
        // Note that materials can record updates in between calls to update() and/or return flags from their update() calls.
        Material::UpdateFlags updateFlags = Material::UpdateFlags::None;
        mMaterialsUpdateFlags.resize(mMaterials.size());
        std::fill(mMaterialsUpdateFlags.begin(), mMaterialsUpdateFlags.end(), Material::UpdateFlags::None);

        auto updateMaterial = [&](const MaterialID materialID) {
            auto& pMaterial = getMaterial(materialID);
            if (pMaterial->mpDevice != mpDevice)
                FALCOR_THROW("Material '{}' was created with a different device than the MaterialSystem.", pMaterial->getName());
            Material::UpdateFlags flags = pMaterial->update(this);
            // Record update flags.
            mMaterialsUpdateFlags[materialID.get()] = flags;
            updateFlags |= flags;
        };

        if (forceUpdate || mMaterialUpdates != Material::UpdateFlags::None)
        {
            mpTextureManager->beginDeferredLoading();

            for (size_t materialIdx = 0; materialIdx < mMaterials.size(); ++materialIdx)
                updateMaterial(MaterialID{ materialIdx });

            mpTextureManager->endDeferredLoading();
        }
        else
        {
            for (const auto& materialID : mDynamicMaterialIDs)
                updateMaterial(materialID);
        }

        if (reupdateMetadata)
        {
            updateMetadata();