C++ UsdPrim::GetReferences方法代码示例

TfToken usdWriteJob::writeVariants(const UsdPrim &usdRootPrim)
{
    // Init parameters for filtering and setting the active variant
    std::string defaultModelingVariant;

    // Get the usdVariantRootPrimPath (optionally filter by renderLayer prefix)
    MayaPrimWriterPtr firstPrimWriterPtr = *mMayaPrimWriterList.begin();
    std::string firstPrimWriterPathStr( firstPrimWriterPtr->getDagPath().fullPathName().asChar() );
    std::replace( firstPrimWriterPathStr.begin(), firstPrimWriterPathStr.end(), '|', '/');
    std::replace( firstPrimWriterPathStr.begin(), firstPrimWriterPathStr.end(), ':', '_'); // replace namespace ":" with "_"
    SdfPath usdVariantRootPrimPath(firstPrimWriterPathStr);
    usdVariantRootPrimPath = usdVariantRootPrimPath.GetPrefixes()[0];

    // Create a new usdVariantRootPrim and reference the Base Model UsdRootPrim
    //   This is done for reasons as described above under mArgs.usdModelRootOverridePath
    UsdPrim usdVariantRootPrim = mStage->DefinePrim(usdVariantRootPrimPath);
    TfToken defaultPrim = usdVariantRootPrim.GetName();
    usdVariantRootPrim.GetReferences().AppendInternalReference(usdRootPrim.GetPath());
    usdVariantRootPrim.SetActive(true);
    usdRootPrim.SetActive(false);

    // Loop over all the renderLayers
    for (unsigned int ir=0; ir < mRenderLayerObjs.length(); ++ir) {
        SdfPathTable<bool> tableOfActivePaths;
        MFnRenderLayer renderLayerFn( mRenderLayerObjs[ir] );
        MString renderLayerName = renderLayerFn.name();
        std::string variantName(renderLayerName.asChar());
        // Determine default variant. Currently unsupported
        //MPlug renderLayerDisplayOrderPlug = renderLayerFn.findPlug("displayOrder", true);
        //int renderLayerDisplayOrder = renderLayerDisplayOrderPlug.asShort();
                    
        // The Maya default RenderLayer is also the default modeling variant
        if (mRenderLayerObjs[ir] == MFnRenderLayer::defaultRenderLayer()) {
            defaultModelingVariant=variantName;
        }
        
        // Make the renderlayer being looped the current one
        MGlobal::executeCommand(MString("editRenderLayerGlobals -currentRenderLayer ")+
                                        renderLayerName, false, false);

        // == ModelingVariants ==
        // Identify prims to activate
        // Put prims and parent prims in a SdfPathTable
        // Then use that membership to determine if a prim should be Active.
        // It has to be done this way since SetActive(false) disables access to all child prims.
        MObjectArray renderLayerMemberObjs;
        renderLayerFn.listMembers(renderLayerMemberObjs);
        std::vector< SdfPath > activePaths;
        for (unsigned int im=0; im < renderLayerMemberObjs.length(); ++im) {
            MFnDagNode dagFn(renderLayerMemberObjs[im]);
            MDagPath dagPath;
            dagFn.getPath(dagPath);
            dagPath.extendToShape();
            SdfPath usdPrimPath; 
            if (!TfMapLookup(mDagPathToUsdPathMap, dagPath, &usdPrimPath)) {
                continue;
            }
            usdPrimPath = usdPrimPath.ReplacePrefix(usdPrimPath.GetPrefixes()[0], usdVariantRootPrimPath); // Convert base to variant usdPrimPath
            tableOfActivePaths[usdPrimPath] = true;
            activePaths.push_back(usdPrimPath);
            //UsdPrim usdPrim = mStage->GetPrimAtPath(usdPrimPath);
            //usdPrim.SetActive(true);
        }
        if (!tableOfActivePaths.empty()) {
            { // == BEG: Scope for Variant EditContext
                // Create the variantSet and variant
                UsdVariantSet modelingVariantSet = usdVariantRootPrim.GetVariantSets().AppendVariantSet("modelingVariant");
                modelingVariantSet.AppendVariant(variantName);
                modelingVariantSet.SetVariantSelection(variantName);
                // Set the Edit Context
                UsdEditTarget editTarget = modelingVariantSet.GetVariantEditTarget();
                UsdEditContext editContext(mStage, editTarget);

                // == Activate/Deactivate UsdPrims
                UsdPrimRange it = UsdPrimRange::AllPrims(mStage->GetPseudoRoot());
                std::vector<UsdPrim> primsToDeactivate;
                for ( ; it; ++it) {
                    UsdPrim usdPrim = *it;
                    // For all xformable usdPrims...
                    if (usdPrim && usdPrim.IsA<UsdGeomXformable>()) {
                        bool isActive=false;
                        for (size_t j=0;j<activePaths.size();j++) {
                            //primPathD.HasPrefix(primPathA);
                            SdfPath activePath=activePaths[j];
                            if (usdPrim.GetPath().HasPrefix(activePath) || activePath.HasPrefix(usdPrim.GetPath())) {
                                isActive=true; break;
                            }
                        }
                        if (isActive==false) {
                            primsToDeactivate.push_back(usdPrim);
                            it.PruneChildren();
                        }
                    }
                }
                // Now deactivate the prims (done outside of the UsdPrimRange 
                // so not to modify the iterator while in the loop)
                for ( UsdPrim const& prim : primsToDeactivate ) {
                    prim.SetActive(false);
                }
            } // == END: Scope for Variant EditContext
//.........这里部分代码省略.........