python: expose mesh-to-mesh and in-place mesh conversion.

Needs to fetch MeshOptimizer on the CIs for testing this as there's no
other plugin with these features right now.

doc/python/magnum.trade.rst

@@ -500,8 +500,14 @@
     raising an exception. See particular function documentation for detailed
     behavior.
 
+.. py:function:: magnum.trade.AbstractSceneConverter.convert
+    :raise RuntimeError: If conversion fails
+
+.. py:function:: magnum.trade.AbstractSceneConverter.convert_in_place
+    :raise RuntimeError: If conversion fails
+
 .. py:function:: magnum.trade.AbstractSceneConverter.convert_to_file
-    :raise RuntimeError: If scene conversion fails
+    :raise RuntimeError: If conversion fails
 
     For compatibility with :ref:`os.path`, on Windows this function converts
     all backslashes in :p:`filename` to forward slashes before passing it to

package/ci/appveyor-desktop-gles.bat

@@ -78,6 +78,7 @@ cmake .. ^
     -DMAGNUM_BUILD_STATIC=%BUILD_STATIC% ^
     -DMAGNUM_WITH_DDSIMPORTER=ON ^
     -DMAGNUM_WITH_GLTFIMPORTER=ON ^
+    -DMAGNUM_WITH_MESHOPTIMIZERSCENECONVERTER=ON ^
     -DMAGNUM_WITH_STANFORDSCENECONVERTER=ON ^
     -DMAGNUM_WITH_STBIMAGECONVERTER=ON ^
     -DMAGNUM_WITH_STBIMAGEIMPORTER=ON ^

package/ci/appveyor-desktop.bat

@@ -12,6 +12,9 @@ rem currently disabled -- https://github.com/catchorg/Catch2/issues/1113
 if "%COMPILER%" == "msvc-clang" if "%APPVEYOR_BUILD_WORKER_IMAGE%" == "Visual Studio 2022" set COMPILER_EXTRA=-DCMAKE_CXX_COMPILER="C:/Program Files/Microsoft Visual Studio/2022/Community/VC/Tools/Llvm/bin/clang-cl.exe" -DCMAKE_LINKER="C:/Program Files/Microsoft Visual Studio/2022/Community/VC/Tools/Llvm/bin/lld-link.exe" -DCMAKE_CXX_FLAGS="-m64 /EHsc"
 if "%COMPILER%" == "msvc-clang" if "%APPVEYOR_BUILD_WORKER_IMAGE%" == "Visual Studio 2019" set COMPILER_EXTRA=-DCMAKE_CXX_COMPILER="C:/Program Files (x86)/Microsoft Visual Studio/2019/Community/VC/Tools/Llvm/bin/clang-cl.exe" -DCMAKE_LINKER="C:/Program Files (x86)/Microsoft Visual Studio/2019/Community/VC/Tools/Llvm/bin/lld-link.exe" -DCMAKE_CXX_FLAGS="-m64 /EHsc"
 
+set EXCEPT_MSVC2017=ON
+IF "%APPVEYOR_BUILD_WORKER_IMAGE%" == "Visual Studio 2017" set EXCEPT_MSVC2017=OFF
+
 rem Build pybind11. Downloaded in the appveyor.yml script.
 cd pybind11-%PYBIND% || exit /b
 mkdir -p build && cd build || exit /b
@@ -85,6 +88,7 @@ cmake .. ^
     -DMAGNUM_BUILD_STATIC=%BUILD_STATIC% ^
     -DMAGNUM_WITH_DDSIMPORTER=ON ^
     -DMAGNUM_WITH_GLTFIMPORTER=ON ^
+    -DMAGNUM_WITH_MESHOPTIMIZERSCENECONVERTER=%EXCEPT_MSVC2017% ^
     -DMAGNUM_WITH_STANFORDSCENECONVERTER=ON ^
     -DMAGNUM_WITH_STBIMAGECONVERTER=ON ^
     -DMAGNUM_WITH_STBIMAGEIMPORTER=ON ^

package/ci/appveyor.yml

@@ -123,6 +123,12 @@ install:
 - IF "%TARGET%" == "desktop" 7z x glfw-3.2.1.bin.WIN64.zip && ren glfw-3.2.1.bin.WIN64 glfw && mkdir deps && mkdir deps\lib && mkdir deps\bin && mkdir deps\include && xcopy /e glfw\include\* deps\include\
 - IF "%TARGET%" == "desktop" IF "%COMPILER:~0,4%" == "msvc" copy glfw\lib-vc2015\glfw3.dll deps\bin\ && copy glfw\lib-vc2015\glfw3dll.lib deps\lib\glfw3.lib
 
+# meshoptimizer for MSVC 2022, 2019 and clang-cl; MinGW. MSVC 2017 doesn't work
+# with the 2019 build unfortunately, and can't build it because of
+# https://github.com/actions/runner-images/issues/3294
+- IF "%COMPILER:~0,4%" == "msvc" appveyor DownloadFile https://ci.magnum.graphics/meshoptimizer-0.18-windows-2019-debug.zip && 7z x meshoptimizer-0.18-windows-2019-debug.zip -o%APPVEYOR_BUILD_FOLDER%\deps
+- IF "%COMPILER%" == "mingw" appveyor DownloadFile https://ci.magnum.graphics/meshoptimizer-0.18-windows-mingw.zip && 7z x meshoptimizer-0.18-windows-mingw.zip -o%APPVEYOR_BUILD_FOLDER%\deps
+
 build_script:
 - IF "%TARGET%" == "desktop" IF "%COMPILER:~0,4%" == "msvc" call package\ci\appveyor-desktop.bat
 - IF "%TARGET%" == "desktop-gles" call package\ci\appveyor-desktop-gles.bat

package/ci/circleci.yml

@@ -128,6 +128,23 @@ commands:
           wget https://ci.magnum.graphics/swiftshader-gles-r5464.a6940c8e6e-<< parameters.build >>.zip
           unzip swiftshader-gles-r5464.a6940c8e6e-<< parameters.build >>.zip
 
+  install-meshoptimizer:
+    steps:
+    - run:
+        name: Install meshoptimizer
+        # few commits after 0.14 with a fix for old Apple Clang
+        command: |
+          export MESHOPTIMIZER_VERSION=97c52415c6d29f297a76482ddde22f739292446d
+          mkdir -p $HOME/meshoptimizer && cd $HOME/meshoptimizer
+          wget -nc --no-check-certificate https://github.com/zeux/meshoptimizer/archive/$MESHOPTIMIZER_VERSION.tar.gz
+          tar --strip-components=1 -xzf $MESHOPTIMIZER_VERSION.tar.gz
+          mkdir build && cd build
+          cmake .. -DCMAKE_BUILD_TYPE=Debug \
+            -DCMAKE_POSITION_INDEPENDENT_CODE=ON \
+            -DCMAKE_INSTALL_PREFIX=$HOME/deps \
+            -G Ninja
+          ninja install
+
   build:
     parameters:
       script:
@@ -172,6 +189,7 @@ jobs:
     - install-cmake-3_4
     - install-python-3_6
     - install-pybind11
+    - install-meshoptimizer
     - build:
         script: unix-desktop.sh
     - lcov
@@ -193,6 +211,7 @@ jobs:
     - install-cmake-3_4
     - install-python-3_6
     - install-pybind11
+    - install-meshoptimizer
     - install-swiftshader-gles:
         build: ubuntu-16.04
     - build:
@@ -216,6 +235,7 @@ jobs:
     - install-cmake-3_4
     - install-python-3_6
     - install-pybind11
+    - install-meshoptimizer
     - install-swiftshader-gles:
         build: ubuntu-16.04
     - build:
@@ -240,6 +260,7 @@ jobs:
     - install-cmake-3_4
     - install-python-3_6
     - install-pybind11
+    - install-meshoptimizer
     - build:
         script: unix-desktop.sh
     - lcov
@@ -251,7 +272,8 @@ jobs:
       PLATFORM_GL_API: CGL
     steps:
     - install-base-macos:
-        extra: sdl2 glfw numpy pybind11
+        extra: sdl2 glfw wget numpy pybind11
+    - install-meshoptimizer
     - build:
         script: unix-desktop.sh
     - lcov
@@ -268,6 +290,7 @@ jobs:
         extra: sdl2 glfw wget numpy pybind11
     - install-swiftshader-gles:
         build: macos-10.15
+    - install-meshoptimizer
     - build:
         script: unix-desktop-gles.sh
     - lcov
@@ -281,7 +304,8 @@ jobs:
       PLATFORM_GL_API: CGL
     steps:
     - install-base-macos:
-        extra: sdl2 glfw numpy pybind11
+        extra: sdl2 glfw wget numpy pybind11
+    - install-meshoptimizer
     - build:
         script: unix-desktop.sh
     - lcov

package/ci/unix-desktop-gles.sh

@@ -65,6 +65,7 @@ cmake .. \
     -DMAGNUM_BUILD_STATIC=$BUILD_STATIC \
     -DMAGNUM_WITH_DDSIMPORTER=ON \
     -DMAGNUM_WITH_GLTFIMPORTER=ON \
+    -DMAGNUM_WITH_MESHOPTIMIZERSCENECONVERTER=ON \
     -DMAGNUM_WITH_STANFORDSCENECONVERTER=ON \
     -DMAGNUM_WITH_STBIMAGECONVERTER=ON \
     -DMAGNUM_WITH_STBIMAGEIMPORTER=ON \

package/ci/unix-desktop.sh

@@ -69,6 +69,7 @@ cmake .. \
     -DMAGNUM_BUILD_STATIC=$BUILD_STATIC \
     -DMAGNUM_WITH_DDSIMPORTER=ON \
     -DMAGNUM_WITH_GLTFIMPORTER=ON \
+    -DMAGNUM_WITH_MESHOPTIMIZERSCENECONVERTER=ON \
     -DMAGNUM_WITH_STANFORDSCENECONVERTER=ON \
     -DMAGNUM_WITH_STBIMAGECONVERTER=ON \
     -DMAGNUM_WITH_STBIMAGEIMPORTER=ON \

src/python/magnum/test/test_trade.py

@@ -1466,6 +1466,62 @@ class SceneConverter(unittest.TestCase):
         self.assertEqual(converter.flags, trade.SceneConverterFlags.VERBOSE)
 
     def test_mesh(self):
+        importer = trade.ImporterManager().load_and_instantiate('GltfImporter')
+        importer.open_file(os.path.join(os.path.dirname(__file__), 'mesh.gltf'))
+        mesh = importer.mesh('Indexed mesh')
+
+        converter_manager = converter = trade.SceneConverterManager()
+        if 'MeshOptimizerSceneConverter' not in converter_manager.plugin_list:
+            self.skipTest("MeshOptimizerSceneConverter plugin not available")
+
+        converter = trade.SceneConverterManager().load_and_instantiate('MeshOptimizerSceneConverter')
+
+        converted_mesh = converter.convert(mesh)
+        self.assertEqual(converted_mesh.index_count, mesh.index_count)
+
+    def test_mesh_failed(self):
+        importer = trade.ImporterManager().load_and_instantiate('GltfImporter')
+        importer.open_file(os.path.join(os.path.dirname(__file__), 'mesh.gltf'))
+        mesh = importer.mesh('Non-indexed mesh')
+
+        converter_manager = converter = trade.SceneConverterManager()
+        if 'MeshOptimizerSceneConverter' not in converter_manager.plugin_list:
+            self.skipTest("MeshOptimizerSceneConverter plugin not available")
+
+        converter = trade.SceneConverterManager().load_and_instantiate('MeshOptimizerSceneConverter')
+
+        with self.assertRaisesRegex(RuntimeError, "conversion failed"):
+            converted_mesh = converter.convert(mesh)
+
+    def test_mesh_in_place(self):
+        importer = trade.ImporterManager().load_and_instantiate('GltfImporter')
+        importer.open_file(os.path.join(os.path.dirname(__file__), 'mesh.gltf'))
+        mesh = importer.mesh('Indexed mesh')
+
+        converter_manager = converter = trade.SceneConverterManager()
+        if 'MeshOptimizerSceneConverter' not in converter_manager.plugin_list:
+            self.skipTest("MeshOptimizerSceneConverter plugin not available")
+
+        converter = trade.SceneConverterManager().load_and_instantiate('MeshOptimizerSceneConverter')
+
+        converter.convert_in_place(mesh)
+        self.assertEqual(mesh.index_count, 3)
+
+    def test_mesh_in_place_failed(self):
+        importer = trade.ImporterManager().load_and_instantiate('GltfImporter')
+        importer.open_file(os.path.join(os.path.dirname(__file__), 'mesh.gltf'))
+        mesh = importer.mesh('Non-indexed mesh')
+
+        converter_manager = converter = trade.SceneConverterManager()
+        if 'MeshOptimizerSceneConverter' not in converter_manager.plugin_list:
+            self.skipTest("MeshOptimizerSceneConverter plugin not available")
+
+        converter = trade.SceneConverterManager().load_and_instantiate('MeshOptimizerSceneConverter')
+
+        with self.assertRaisesRegex(RuntimeError, "conversion failed"):
+            converter.convert_in_place(mesh)
+
+    def test_mesh_to_file(self):
         importer = trade.ImporterManager().load_and_instantiate('GltfImporter')
         importer.open_file(os.path.join(os.path.dirname(__file__), 'mesh.gltf'))
         mesh = importer.mesh(1)
@@ -1476,7 +1532,7 @@ class SceneConverter(unittest.TestCase):
             converter.convert_to_file(mesh, os.path.join(tmp, "mesh.ply"))
             self.assertTrue(os.path.exists(os.path.join(tmp, "mesh.ply")))
 
-    def test_mesh_failed(self):
+    def test_mesh_to_file_failed(self):
         importer = trade.ImporterManager().load_and_instantiate('GltfImporter')
         importer.open_file(os.path.join(os.path.dirname(__file__), 'mesh.gltf'))
         mesh = importer.mesh(1)

src/python/magnum/trade.cpp

@@ -1640,6 +1640,24 @@ void trade(py::module_& m) {
         }, [](Trade::AbstractSceneConverter& self, Trade::SceneConverterFlag flags) {
             self.setFlags(flags);
         }, "Converter flags")
+        .def("convert", [](Trade::AbstractSceneConverter& self, const Trade::MeshData& mesh) {
+            /** @todo log redirection -- but we'd need assertions to not be
+                part of that so when it dies, the user can still see why */
+            Containers::Optional<Trade::MeshData> out = self.convert(mesh);
+            if(!out) {
+                PyErr_SetString(PyExc_RuntimeError, "conversion failed");
+                throw py::error_already_set{};
+            }
+            return out;
+        }, "Convert a mesh", py::arg("mesh"))
+        .def("convert_in_place", [](Trade::AbstractSceneConverter& self, Trade::MeshData& mesh) {
+            /** @todo log redirection -- but we'd need assertions to not be
+                part of that so when it dies, the user can still see why */
+            if(!self.convertInPlace(mesh)) {
+                PyErr_SetString(PyExc_RuntimeError, "conversion failed");
+                throw py::error_already_set{};
+            }
+        }, "Convert a mesh", py::arg("mesh"))
         /** @todo drop std::string in favor of our own string caster */
         .def("convert_to_file", [](Trade::AbstractSceneConverter& self, const Trade::MeshData& mesh, const std::string& filename) {
             /** @todo log redirection -- but we'd need assertions to not be