Autodesk · pierrebai-adsk · Aug 3, 2023
diff --git a/lib/mayaUsd/commands/Readme.md b/lib/mayaUsd/commands/Readme.md
@@ -48,7 +48,8 @@ Each base command class is documented in the following sections.
 | `-verbose`                    | `-v`       | noarg          | false                             | Make the command output more verbose. |
 | `-variant`                    | `-var`     | string[2]      | none                              | Set variant key value pairs |
 | `-importUSDZTextures`         | `-itx`     | bool           | false                             | Imports textures from USDZ archives during import to disk. Can be used in conjuction with `-importUSDZTexturesFilePath` to specify an explicit directory to write imported textures to. If not specified, requires a Maya project to be set in the current context.  |
-| `-importUSDZTexturesFilePath` | `-itf`     | string         | none                              | Specifies an explicit directory to write imported textures to from a USDZ archive. Has no effect if `-importUSDZTextures` is not specified.
+| `-importUSDZTexturesFilePath` | `-itf`     | string         | none                              | Specifies an explicit directory to write imported textures to from a USDZ archive. Has no effect if `-importUSDZTextures` is not specified. |
+| `-importRelativeTextures`     | `-rtx`     | string         | none                              | Selects how textures filenames are generated: absolute, relative, automatic or none. When automatic, the filename is relative if the source filename of the texture being imported is relative. When none, the file path is left alone, for backward compatible behavior. |
 
 ### Return Value
 

diff --git a/lib/mayaUsd/commands/baseImportCommand.cpp b/lib/mayaUsd/commands/baseImportCommand.cpp
@@ -64,6 +64,10 @@ MSyntax MayaUSDImportCommand::createSyntax()
         kImportUSDZTexturesFilePathFlag,
         UsdMayaJobImportArgsTokens->importUSDZTexturesFilePath.GetText(),
         MSyntax::kString);
+    syntax.addFlag(
+        kImportRelativeTexturesFlag,
+        UsdMayaJobImportArgsTokens->importRelativeTextures.GetText(),
+        MSyntax::kString);
     syntax.addFlag(kMetadataFlag, UsdMayaJobImportArgsTokens->metadata.GetText(), MSyntax::kString);
     syntax.makeFlagMultiUse(kMetadataFlag);
     syntax.addFlag(

diff --git a/lib/mayaUsd/commands/baseImportCommand.h b/lib/mayaUsd/commands/baseImportCommand.h
@@ -45,6 +45,7 @@ class MAYAUSD_CORE_PUBLIC MayaUSDImportCommand : public MPxCommand
     static constexpr auto kImportInstancesFlag = "ii";
     static constexpr auto kImportUSDZTexturesFlag = "itx";
     static constexpr auto kImportUSDZTexturesFilePathFlag = "itf";
+    static constexpr auto kImportRelativeTexturesFlag = "rtx";
     static constexpr auto kMetadataFlag = "md";
     static constexpr auto kApiSchemaFlag = "api";
     static constexpr auto kJobContextFlag = "jc";

diff --git a/lib/mayaUsd/fileio/jobs/jobArgs.cpp b/lib/mayaUsd/fileio/jobs/jobArgs.cpp
@@ -1151,6 +1151,14 @@ UsdMayaJobImportArgs::UsdMayaJobImportArgs(
           UsdMayaPreferredMaterialTokens->allTokens))
     , importUSDZTexturesFilePath(UsdMayaJobImportArgs::GetImportUSDZTexturesFilePath(userArgs))
     , importUSDZTextures(extractBoolean(userArgs, UsdMayaJobImportArgsTokens->importUSDZTextures))
+    , importRelativeTextures(extractToken(
+          userArgs,
+          UsdMayaJobImportArgsTokens->importRelativeTextures,
+          UsdMayaJobImportArgsTokens->none,
+          { UsdMayaJobImportArgsTokens->automatic,
+            UsdMayaJobImportArgsTokens->absolute,
+            UsdMayaJobImportArgsTokens->relative,
+            UsdMayaJobImportArgsTokens->none }))
     , importInstances(extractBoolean(userArgs, UsdMayaJobImportArgsTokens->importInstances))
     , useAsAnimationCache(extractBoolean(userArgs, UsdMayaJobImportArgsTokens->useAsAnimationCache))
     , importWithProxyShapes(importWithProxyShapes)
@@ -1209,6 +1217,8 @@ const VtDictionary& UsdMayaJobImportArgs::GetDefaultDictionary()
         d[UsdMayaJobImportArgsTokens->importInstances] = true;
         d[UsdMayaJobImportArgsTokens->importUSDZTextures] = false;
         d[UsdMayaJobImportArgsTokens->importUSDZTexturesFilePath] = "";
+        d[UsdMayaJobImportArgsTokens->importRelativeTextures]
+            = UsdMayaJobImportArgsTokens->none.GetString();
         d[UsdMayaJobImportArgsTokens->pullImportStage] = UsdStageRefPtr();
         d[UsdMayaJobImportArgsTokens->useAsAnimationCache] = false;
         d[UsdMayaJobImportArgsTokens->preserveTimeline] = false;
@@ -1289,6 +1299,7 @@ const VtDictionary& UsdMayaJobImportArgs::GetGuideDictionary()
         d[UsdMayaJobImportArgsTokens->importInstances] = _boolean;
         d[UsdMayaJobImportArgsTokens->importUSDZTextures] = _boolean;
         d[UsdMayaJobImportArgsTokens->importUSDZTexturesFilePath] = _string;
+        d[UsdMayaJobImportArgsTokens->importRelativeTextures] = _string;
         d[UsdMayaJobImportArgsTokens->pullImportStage] = _usdStageRefPtr;
         d[UsdMayaJobImportArgsTokens->useAsAnimationCache] = _boolean;
         d[UsdMayaJobImportArgsTokens->preserveTimeline] = _boolean;
@@ -1377,6 +1388,7 @@ std::ostream& operator<<(std::ostream& out, const UsdMayaJobImportArgs& importAr
         << "importInstances: " << TfStringify(importArgs.importInstances) << std::endl
         << "importUSDZTextures: " << TfStringify(importArgs.importUSDZTextures) << std::endl
         << "importUSDZTexturesFilePath: " << TfStringify(importArgs.importUSDZTexturesFilePath)
+        << "importRelativeTextures: " << TfStringify(importArgs.importRelativeTextures) << std::endl
         << "pullImportStage: " << TfStringify(importArgs.pullImportStage) << std::endl
         << std::endl
         << "timeInterval: " << importArgs.timeInterval << std::endl

diff --git a/lib/mayaUsd/fileio/jobs/jobArgs.h b/lib/mayaUsd/fileio/jobs/jobArgs.h
@@ -155,8 +155,14 @@ TF_DECLARE_PUBLIC_TOKENS(
     (importInstances) \
     (importUSDZTextures) \
     (importUSDZTexturesFilePath) \
+    (importRelativeTextures) \
     (pullImportStage) \
     (preserveTimeline) \
+    /* values for import relative textures */ \
+    (automatic) \
+    (absolute) \
+    (relative) \
+    (none) \
     /* assemblyRep values */ \
     (Collapsed) \
     (Full) \
@@ -348,6 +354,7 @@ struct UsdMayaJobImportArgs
     const TfToken        preferredMaterial;
     const std::string    importUSDZTexturesFilePath;
     const bool           importUSDZTextures;
+    const std::string    importRelativeTextures;
     const bool           importInstances;
     const bool           useAsAnimationCache;
     const bool           importWithProxyShapes;

diff --git a/lib/mayaUsd/python/wrapPrimReader.cpp b/lib/mayaUsd/python/wrapPrimReader.cpp
@@ -462,6 +462,7 @@ void wrapJobImportArgs()
         .def_readonly("importUSDZTextures", &UsdMayaJobImportArgs::importUSDZTextures)
         .def_readonly(
             "importUSDZTexturesFilePath", &UsdMayaJobImportArgs::importUSDZTexturesFilePath)
+        .def_readonly("importRelativeTextures", &UsdMayaJobImportArgs::importRelativeTextures)
         .def_readonly("importWithProxyShapes", &UsdMayaJobImportArgs::importWithProxyShapes)
         .add_property(
             "includeAPINames",

diff --git a/lib/mayaUsd/utils/utilFileSystem.cpp b/lib/mayaUsd/utils/utilFileSystem.cpp
@@ -174,14 +174,20 @@ std::pair<std::string, bool> UsdMayaUtilFileSystem::makePathRelativeTo(
     return std::make_pair(relativePath.generic_string(), true);
 }
 
+std::string UsdMayaUtilFileSystem::getProjectPath()
+{
+    MString projectPath = MGlobal::executeCommandStringResult("workspace -q -rd");
+    return projectPath.asChar();
+}
+
 std::string UsdMayaUtilFileSystem::getPathRelativeToProject(const std::string& fileName)
 {
     if (fileName.empty())
         return {};
 
-    MString projectPath = MGlobal::executeCommandStringResult("workspace -q -rd");
     // Note: don't use isEmpty() because it is not available in Maya 2022 and earlier.
-    if (projectPath.length() == 0)
+    const std::string projectPath = getProjectPath();
+    if (projectPath.empty())
         return {};
 
     // Note: we do *not* use filesystem function to attempt to make the
@@ -191,18 +197,35 @@ std::string UsdMayaUtilFileSystem::getPathRelativeToProject(const std::string& f
     //       preserve paths entered manually with relative folder ("..")
     //       by keping an absolute path with ".." embedded in them,
     //       so this works even in this situation.
-    const auto pos = fileName.find(projectPath.asChar());
+    const auto pos = fileName.find(projectPath);
     if (pos != 0)
         return {};
 
-    auto relativePathAndSuccess = makePathRelativeTo(fileName, projectPath.asChar());
+    auto relativePathAndSuccess = makePathRelativeTo(fileName, projectPath);
 
     if (!relativePathAndSuccess.second)
         return {};
 
     return relativePathAndSuccess.first;
 }
 
+std::string UsdMayaUtilFileSystem::makeProjectRelatedPath(const std::string& fileName)
+{
+    const std::string projectPath = UsdMayaUtilFileSystem::getProjectPath();
+    if (projectPath.empty())
+        return {};
+
+    // Attempt to create a relative path relative to the project folder.
+    // If that fails, we cannot create the project-relative path.
+    const auto pathAndSuccess = UsdMayaUtilFileSystem::makePathRelativeTo(fileName, projectPath);
+    if (!pathAndSuccess.second)
+        return {};
+
+    // Make the path absolute but relative to the project folder. That is an absolute
+    // path that starts with the project path.
+    return UsdMayaUtilFileSystem::appendPaths(projectPath, pathAndSuccess.first);
+}
+
 std::string UsdMayaUtilFileSystem::getPathRelativeToDirectory(
     const std::string& fileName,
     const std::string& relativeToDir)

diff --git a/lib/mayaUsd/utils/utilFileSystem.h b/lib/mayaUsd/utils/utilFileSystem.h
@@ -89,6 +89,17 @@ getPathRelativeToDirectory(const std::string& fileName, const std::string& relat
 MAYAUSD_CORE_PUBLIC
 std::string getPathRelativeToProject(const std::string& fileName);
 
+/*! \brief returns the path to the Maya scene project folder.
+ */
+MAYAUSD_CORE_PUBLIC
+std::string getProjectPath();
+
+/*! \brief returns the absolute path of a file but relative to the Maya scene project folder.
+           Returns an empty string if the path cannot be made relative to the project.
+ */
+MAYAUSD_CORE_PUBLIC
+std::string makeProjectRelatedPath(const std::string& fileName);
+
 /*! \brief returns parent directory of a maya scene file opened by reference
  */
 MAYAUSD_CORE_PUBLIC

diff --git a/lib/usd/translators/shading/CMakeLists.txt b/lib/usd/translators/shading/CMakeLists.txt
@@ -3,6 +3,7 @@
 # -----------------------------------------------------------------------------
 target_sources(${TARGET_NAME}
     PRIVATE
+        shadingAsset.cpp
         shadingTokens.cpp
         usdBlinnReader.cpp
         usdBlinnWriter.cpp

diff --git a/lib/usd/translators/shading/mtlxImageReader.cpp b/lib/usd/translators/shading/mtlxImageReader.cpp
@@ -14,6 +14,7 @@
 // limitations under the License.
 //
 #include "mtlxBaseReader.h"
+#include "shadingAsset.h"
 #include "shadingTokens.h"
 
 #include <mayaUsd/fileio/shaderReader.h>
@@ -118,34 +119,8 @@ bool MtlxUsd_ImageReader::Read(UsdMayaPrimReaderContext& context)
     }
 
     // File
-    VtValue val;
-    MPlug   mayaAttr = depFn.findPlug(TrMayaTokens->fileTextureName.GetText(), true, &status);
-
-    UsdShadeInput usdInput = shaderSchema.GetInput(TrMtlxTokens->file);
-    if (status == MS::kSuccess && usdInput && usdInput.Get(&val) && val.IsHolding<SdfAssetPath>()) {
-        std::string filePath = val.UncheckedGet<SdfAssetPath>().GetResolvedPath();
-        if (!filePath.empty() && !ArIsPackageRelativePath(filePath)) {
-            // Maya has issues with relative paths, especially if deep inside a
-            // nesting of referenced assets. Use absolute path instead if USD was
-            // able to resolve. A better fix will require providing an asset
-            // resolver to Maya that can resolve the file correctly using the
-            // MPxFileResolver API. We also make sure the path is not expressed
-            // as a relationship like texture paths inside USDZ assets.
-            val = SdfAssetPath(filePath);
-        }
-
-        // NOTE: Will need UDIM support and potentially USDZ support. When that happens, consider
-        // refactoring existing code from usdUVTextureReader.cpp as shared utilities.
-        UsdMayaReadUtil::SetMayaAttr(mayaAttr, val);
-
-        // colorSpace:
-        if (usdInput.GetAttr().HasColorSpace()) {
-            MString colorSpace = usdInput.GetAttr().GetColorSpace().GetText();
-            mayaAttr = depFn.findPlug(TrMayaTokens->colorSpace.GetText(), true, &status);
-            if (status == MS::kSuccess) {
-                mayaAttr.setString(colorSpace);
-            }
-        }
+    if (!ResolveTextureAssetPath(prim, shaderSchema, depFn, _GetArgs().GetJobArguments())) {
+        return false;
     }
 
     // Default color
@@ -158,8 +133,9 @@ bool MtlxUsd_ImageReader::Read(UsdMayaPrimReaderContext& context)
     }
 
     // Filter type:
-    mayaAttr = depFn.findPlug(TrMayaTokens->filterType.GetText(), true, &status);
-    usdInput = shaderSchema.GetInput(TrMtlxTokens->filtertype);
+    MPlug         mayaAttr = depFn.findPlug(TrMayaTokens->filterType.GetText(), true, &status);
+    UsdShadeInput usdInput = shaderSchema.GetInput(TrMtlxTokens->filtertype);
+    VtValue       val;
     if (status == MS::kSuccess && usdInput && usdInput.Get(&val) && val.IsHolding<std::string>()) {
         std::string filterType = val.UncheckedGet<std::string>();
         if (filterType == TrMtlxTokens->closest.GetString()) {