Add support for df_vulkan as MDL test renderer (#2743)

Wrapper code based on that for the OSL test renderer and intermediate code from #2254.

The new CMake variable MATERIALX_MDL_BINARY_TESTRENDER contains the path of the df_vulkan binary, and is derived from MATERIALX_MDL_SDK_DIR.

Use x64-windows-release triplet for the MDL SDK to save disk space on the runners (and build time).

Author: jreichel-nvidia

.github/workflows/main.yml

@@ -174,8 +174,8 @@ jobs:
     - name: Install MDL SDK
       if: env.IS_EXTENDED_BUILD == 'true' && matrix.extended_build_mdl_sdk == 'ON' && runner.os == 'Windows'
       run: |
-        C:/vcpkg/vcpkg install mdl-sdk --triplet=x64-windows
-        Add-Content $env:GITHUB_PATH "C:/vcpkg/installed/x64-windows/bin"
+        C:/vcpkg/vcpkg install mdl-sdk[dds,df-vulkan,openimageio] --triplet=x64-windows-release
+        Add-Content $env:GITHUB_PATH "C:/vcpkg/installed/x64-windows-release/bin"
 
     - name: Install Python ${{ matrix.python }}
       if: matrix.python != 'None'
@@ -198,13 +198,13 @@ jobs:
         EXTENDED_BUILD_CONFIG=""
         if [ "${{ env.IS_EXTENDED_BUILD }}" == "true" ]; then
           if [ "${{ runner.os }}" == "Windows" ]; then
-            EXTENDED_BUILD_CONFIG="-DCMAKE_TOOLCHAIN_FILE=C:/vcpkg/scripts/buildsystems/vcpkg.cmake -DVCPKG_TARGET_TRIPLET=x64-windows"
+            EXTENDED_BUILD_CONFIG="-DCMAKE_TOOLCHAIN_FILE=C:/vcpkg/scripts/buildsystems/vcpkg.cmake"
           fi
           if [ "${{ matrix.extended_build_oiio }}" == "ON" ]; then
-            EXTENDED_BUILD_CONFIG="$EXTENDED_BUILD_CONFIG -DMATERIALX_BUILD_OIIO=ON"
+            EXTENDED_BUILD_CONFIG="$EXTENDED_BUILD_CONFIG -DVCPKG_TARGET_TRIPLET=x64-windows -DMATERIALX_BUILD_OIIO=ON"
           fi
           if [ "${{ matrix.extended_build_mdl_sdk }}" == "ON" -a "${{ runner.os }}" == "Windows" ]; then
-            EXTENDED_BUILD_CONFIG="$EXTENDED_BUILD_CONFIG -DMATERIALX_MDL_SDK_DIR=C:/vcpkg/installed/x64-windows"
+            EXTENDED_BUILD_CONFIG="$EXTENDED_BUILD_CONFIG -DVCPKG_TARGET_TRIPLET=x64-windows-release -DMATERIALX_MDL_SDK_DIR=C:/vcpkg/installed/x64-windows-release"
           fi
         fi
         TEST_RENDER_CONFIG="-DMATERIALX_TEST_RENDER=OFF"

CMakeLists.txt

@@ -224,6 +224,7 @@ mark_as_advanced(MATERIALX_EMSDK_PATH)
 mark_as_advanced(MATERIALX_BUILD_IOS)
 mark_as_advanced(MATERIALX_BUILD_APPLE_FRAMEWORK)
 mark_as_advanced(MATERIALX_MDL_BINARY_MDLC)
+mark_as_advanced(MATERIALX_MDL_BINARY_TESTRENDER)
 mark_as_advanced(MATERIALX_MDL_MODULE_PATHS)
 mark_as_advanced(MATERIALX_MDL_SDK_DIR)
 mark_as_advanced(MATERIALX_SLANG_RHI_SOURCE_DIR)
@@ -264,11 +265,23 @@ if (MATERIALX_BUILD_BENCHMARK_TESTS)
     add_definitions(-DMATERIALX_BUILD_BENCHMARK_TESTS)
 endif()
 
-# GEN MDL does not have any additional dependencies. For loading and compiling MDL, e.g., in the test renderer, the MDL SDK is needed.
+# MaterialXGenMdl does not have any additional dependencies.
+# MaterialXTest/MaterialXGenMdl performs a syntax check if the mdlc binary is available.
+# MaterialXTest/MaterialXRenderMdl needs the df_vulkan example, SDK library, and image plugins.
 if(MATERIALX_MDL_SDK_DIR)
     find_package(mdl QUIET CONFIG REQUIRED PATHS ${MATERIALX_MDL_SDK_DIR})
     get_target_property(MATERIALX_MDL_BINARY_MDLC mdl::mdlc LOCATION)
     set(MATERIALX_MDL_BINARY_MDLC ${MATERIALX_MDL_BINARY_MDLC} CACHE FILEPATH "Full path to the mdlc binary." FORCE)
+    if((${mdl_VERSION} VERSION_GREATER_EQUAL "2025.0.3") OR (${mdl_VERSION} STREQUAL "trunk"))
+        find_program(MATERIALX_MDL_BINARY_TESTRENDER
+            NAMES df_vulkan
+            HINTS
+                ${MATERIALX_MDL_SDK_DIR}/examples/mdl_sdk/df_vulkan   # regular install layout
+                ${MATERIALX_MDL_SDK_DIR}/tools/mdl-sdk)               # vcpkg layout
+    else()
+        message(WARNING "The MDL df_vulkan test renderer requires an MDL SDK >= 2025.0.3 (found ${mdl_VERSION}).")
+        set(MATERIALX_MDL_BINARY_TESTRENDER "" CACHE FILEPATH "Full path to the MDL df_vulkan test renderer.")
+    endif()
 endif()
 
 # Adjust the default installation path

python/MaterialXTest/tests_to_html.py

@@ -106,7 +106,7 @@ def main(args=None):
     langFiles1 = []
     langPaths1 = []
     for subdir, _, files in os.walk(args.inputdir1):
-        for curFile in files:
+        for curFile in sorted(files):
             if curFile.endswith(args.lang1 + ".png"):
                 langFiles1.append(curFile)
                 langPaths1.append(subdir)

source/MaterialXGenMdl/MdlShaderGenerator.cpp

@@ -220,8 +220,8 @@ ShaderPtr MdlShaderGenerator::generate(const string& name, ElementPtr element, G
              inputSocket->getType().getSemantic() == TypeDesc::SEMANTIC_CLOSURE ||
              inputSocket->getType().getSemantic() == TypeDesc::SEMANTIC_MATERIAL))
         {
-            const string& qualifier = inputSocket->isUniform() || inputSocket->getType() == Type::FILENAME 
-                ? uniformPrefix 
+            const string& qualifier = inputSocket->isUniform() || inputSocket->getType() == Type::FILENAME
+                ? uniformPrefix
                 : EMPTY_STRING;
             const string& type = _syntax->getTypeName(inputSocket->getType());
 

source/MaterialXTest/CMakeLists.txt

@@ -81,6 +81,9 @@ if(MATERIALX_BUILD_RENDER)
     add_subdirectory(MaterialXRenderOsl)
     target_link_libraries(MaterialXTest MaterialXRenderOsl)
   endif()
+  if(MATERIALX_BUILD_GEN_MDL)
+    add_subdirectory(MaterialXRenderMdl)
+  endif()
   if(APPLE AND MATERIALX_BUILD_GEN_MSL)
     add_subdirectory(MaterialXRenderMsl)
     target_link_libraries(MaterialXTest MaterialXRenderMsl)

source/MaterialXTest/MaterialXGenMdl/GenMdl.cpp

@@ -58,13 +58,20 @@ void MdlStringResolver::initialize(
         paths.append(addSp);
     }
 
+    // use a set to remove duplicates while keeping the order
+    auto less = [](const mx::FilePath& lhs, const mx::FilePath& rhs)
+        { return lhs.asString() < rhs.asString(); };
+    std::set<mx::FilePath, decltype(less)> unique_paths(less);
+
     _mdl_searchPaths.clear();
     for (const auto& path : paths)
     {
         // normalize all search paths, as we need this later in `resolve`
         auto normalizedPath = path.getNormalized();
-        if (normalizedPath.exists())
+        if (normalizedPath.exists() && unique_paths.insert(normalizedPath).second)
+        {
             _mdl_searchPaths.append(normalizedPath);
+        }
     }
 
     _logFile = logFile;
@@ -105,7 +112,7 @@ std::string MdlStringResolver::resolve(const std::string& str, const std::string
     }
     if (_logFile)
     {
-        *_logFile << "MaterialX resource can not be accessed through an MDL search path. "
+        *_logFile << "Failed to resolve a MaterialX resource via the given search paths. "
                   << "Dropping the resource from the Material. Resource Path: "
                   << normalizedPath.asString().c_str() << std::endl;
     }
@@ -244,7 +251,7 @@ void MdlShaderGeneratorTester::compileSource(const std::vector<mx::FilePath>& so
     mdlcCommand += " ::" + moduleToTest;
 
     // redirect output
-    mx::FilePath errorFile = moduleToTestPath / (moduleToTest + ".mdl_compile_errors.txt");
+    mx::FilePath errorFile = moduleToTestPath / (moduleToTest + "_log.txt");
     mdlcCommand += " > " + errorFile.asString() + " 2>&1";
 
     // execute the compiler and evaluate return code and the output stream

source/MaterialXTest/MaterialXRenderMdl/CMakeLists.txt

@@ -0,0 +1,23 @@
+file(GLOB_RECURSE source "${CMAKE_CURRENT_SOURCE_DIR}/*.cpp")
+file(GLOB_RECURSE headers "${CMAKE_CURRENT_SOURCE_DIR}/*.h")
+
+target_sources(MaterialXTest PUBLIC ${source} ${headers})
+
+if (NOT MATERIALX_BUILD_MONOLITHIC)
+    get_target_property(MaterialXGenMdl_SOURCE_DIR MaterialXGenMdl SOURCE_DIR)
+else()
+    get_target_property(PROJECT_SOURCE_DIR ${MATERIALX_MONOLITHIC_TARGET} SOURCE_DIR)
+    set(MaterialXGenMdl_SOURCE_DIR "{PROJECT_SOURCE_DIR}/MaterialXGenMdl")
+endif()
+
+target_compile_definitions(MaterialXTest PRIVATE
+    MATERIALX_MDL_BINARY_TESTRENDER=\"${MATERIALX_MDL_BINARY_TESTRENDER}\"
+    MATERIALX_MDL_IMPL_MODULE_PATH=\"${MaterialXGenMdl_SOURCE_DIR}/mdl\"
+    MATERIALX_INSTALL_MDL_MODULE_PATH=\"${MATERIALX_INSTALL_STDLIB_PATH}\"
+    MATERIALX_MDL_MODULE_PATHS=\"${MATERIALX_MDL_MODULE_PATHS}\"
+)
+
+add_tests("${source}")
+
+assign_source_group("Source Files" ${source})
+assign_source_group("Header Files" ${headers})