python: expose basics of trade.AbstractSceneConverter.

doc/python/magnum.trade.rst

@@ -194,3 +194,31 @@
 
 .. py:function:: magnum.trade.AbstractImageConverter.convert_to_file
     :raise RuntimeError: If image conversion fails
+
+.. py:class:: magnum.trade.SceneConverterManager
+    :summary: Manager for :ref:`AbstractSceneConverter` plugin instances
+
+    Each plugin returned by :ref:`instantiate()` or :ref:`load_and_instantiate()`
+    references its owning :ref:`SceneConverterManager` through
+    :ref:`AbstractSceneConverter.manager`, ensuring the manager is not deleted
+    before the plugin instances are.
+
+.. py:class:: magnum.trade.AbstractSceneConverter
+
+    Similarly to C++, image converter plugins are loaded through
+    :ref:`SceneConverterManager`:
+
+    ..
+        >>> from magnum import trade
+
+    .. code:: py
+
+        >>> manager = trade.SceneConverterManager()
+        >>> converter = manager.load_and_instantiate('StanfordSceneConverter')
+
+    Unlike C++, errors in both API usage and file parsing are reported by
+    raising an exception. See particular function documentation for detailed
+    behavior.
+
+.. py:function:: magnum.trade.AbstractSceneConverter.convert_to_file
+    :raise RuntimeError: If scene conversion fails

doc/python/pages/changelog.rst

@@ -90,7 +90,8 @@ Changelog
     :ref:`platform.glfw.Application.exit_event`
 -   Exposed :ref:`platform.glfw.Application.swap_interval` and
     :ref:`platform.glfw.Application.main_loop_iteration`
--   Exposed a basic interface of :ref:`trade.AbstractImageConverter`
+-   Exposed a basic interface of :ref:`trade.AbstractImageConverter` and
+    :ref:`trade.AbstractSceneConverter`
 -   Exposed :ref:`Color3.red()` and other convenience constructors (see
     :gh:`mosra/magnum-bindings#12`)
 -   Fixed issues with an in-source build (see :gh:`mosra/magnum-bindings#13`)

package/ci/appveyor-desktop-gles.bat

@@ -61,6 +61,7 @@ cmake .. ^
     -DWITH_GLFWAPPLICATION=OFF ^
     -DWITH_WINDOWLESSWGLAPPLICATION=ON ^
     -DWITH_ANYIMAGEIMPORTER=ON ^
+    -DWITH_ANYSCENECONVERTER=ON ^
     -G Ninja || exit /b
 cmake --build . || exit /b
 cmake --build . --target install || exit /b
@@ -75,6 +76,7 @@ cmake .. ^
     -DCMAKE_INSTALL_PREFIX=%APPVEYOR_BUILD_FOLDER%/deps ^
     -DBUILD_STATIC=%BUILD_STATIC% ^
     -DWITH_DDSIMPORTER=ON ^
+    -DWITH_STANFORDSCENECONVERTER=ON ^
     -DWITH_STBIMAGECONVERTER=ON ^
     -DWITH_STBIMAGEIMPORTER=ON ^
     -DWITH_CGLTFIMPORTER=ON ^

package/ci/appveyor-desktop.bat

@@ -68,6 +68,7 @@ cmake .. ^
     -DWITH_GLFWAPPLICATION=ON ^
     -DWITH_WINDOWLESSWGLAPPLICATION=ON ^
     -DWITH_ANYIMAGEIMPORTER=ON ^
+    -DWITH_ANYSCENECONVERTER=ON ^
     %COMPILER_EXTRA% -G Ninja || exit /b
 cmake --build . || exit /b
 cmake --build . --target install || exit /b
@@ -82,6 +83,7 @@ cmake .. ^
     -DCMAKE_INSTALL_PREFIX=%APPVEYOR_BUILD_FOLDER%/deps ^
     -DBUILD_STATIC=%BUILD_STATIC% ^
     -DWITH_DDSIMPORTER=ON ^
+    -DWITH_STANFORDSCENECONVERTER=ON ^
     -DWITH_STBIMAGECONVERTER=ON ^
     -DWITH_STBIMAGEIMPORTER=ON ^
     -DWITH_CGLTFIMPORTER=ON ^

package/ci/unix-desktop-gles.sh

@@ -44,6 +44,7 @@ cmake .. \
     -DWITH_VK=OFF \
     -DWITH_WINDOWLESSEGLAPPLICATION=ON \
     -DWITH_ANYIMAGEIMPORTER=ON \
+    -DWITH_ANYSCENECONVERTER=ON \
     -G Ninja
 ninja install
 cd ../..
@@ -54,10 +55,15 @@ cd magnum-plugins
 mkdir build && cd build
 cmake .. \
     -DCMAKE_INSTALL_PREFIX=$HOME/deps \
-    -DCMAKE_INSTALL_RPATH=$HOME/deps/lib \
     -DCMAKE_BUILD_TYPE=Release \
+    `# StanfordSceneConverter uses MeshTools which rely on GL which looks` \
+    `# for OpenGLES. And the RPATH entry needs to be there as well,` \
+    `# otherwise it won't load.` \
+    -DCMAKE_PREFIX_PATH=$HOME/swiftshader \
+    -DCMAKE_INSTALL_RPATH="$HOME/deps/lib;$HOME/swiftshader/lib" \
     -DBUILD_STATIC=$BUILD_STATIC \
     -DWITH_DDSIMPORTER=ON \
+    -DWITH_STANFORDSCENECONVERTER=ON \
     -DWITH_STBIMAGECONVERTER=ON \
     -DWITH_STBIMAGEIMPORTER=ON \
     -DWITH_CGLTFIMPORTER=ON \

package/ci/unix-desktop.sh

@@ -45,6 +45,7 @@ cmake .. \
     -DWITH_SDL2APPLICATION=ON \
     -DWITH_WINDOWLESS${PLATFORM_GL_API}APPLICATION=ON \
     -DWITH_ANYIMAGEIMPORTER=ON \
+    -DWITH_ANYSCENECONVERTER=ON \
     -G Ninja
 
 # In case of a static build there's no way for the test to know the plugin
@@ -66,6 +67,7 @@ cmake .. \
     -DCMAKE_BUILD_TYPE=Release \
     -DBUILD_STATIC=$BUILD_STATIC \
     -DWITH_DDSIMPORTER=ON \
+    -DWITH_STANFORDSCENECONVERTER=ON \
     -DWITH_STBIMAGECONVERTER=ON \
     -DWITH_STBIMAGEIMPORTER=ON \
     -DWITH_CGLTFIMPORTER=ON \

src/python/magnum/test/test_trade.py

@@ -289,3 +289,26 @@ class ImageConverter(unittest.TestCase):
         with tempfile.TemporaryDirectory() as tmp:
             with self.assertRaisesRegex(RuntimeError, "conversion failed"):
                 converter.convert_to_file(image, os.path.join(tmp, "image.hdr"))
+
+class SceneConverter(unittest.TestCase):
+    def test_mesh(self):
+        importer = trade.ImporterManager().load_and_instantiate('CgltfImporter')
+        importer.open_file(os.path.join(os.path.dirname(__file__), 'mesh.glb'))
+        mesh = importer.mesh(0)
+
+        converter = trade.SceneConverterManager().load_and_instantiate('StanfordSceneConverter')
+
+        with tempfile.TemporaryDirectory() as tmp:
+            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):
+        importer = trade.ImporterManager().load_and_instantiate('CgltfImporter')
+        importer.open_file(os.path.join(os.path.dirname(__file__), 'mesh.glb'))
+        mesh = importer.mesh(0)
+
+        converter = trade.SceneConverterManager().load_and_instantiate('AnySceneConverter')
+
+        with tempfile.TemporaryDirectory() as tmp:
+            with self.assertRaisesRegex(RuntimeError, "conversion failed"):
+                converter.convert_to_file(mesh, os.path.join(tmp, "mesh.obj"))

src/python/magnum/trade.cpp

@@ -30,6 +30,7 @@
 #include <Magnum/ImageView.h>
 #include <Magnum/Trade/AbstractImporter.h>
 #include <Magnum/Trade/AbstractImageConverter.h>
+#include <Magnum/Trade/AbstractSceneConverter.h>
 #include <Magnum/Trade/ImageData.h>
 #include <Magnum/Trade/MeshData.h>
 
@@ -253,6 +254,17 @@ template<class T, bool(Trade::AbstractImageConverter::*f)(const T&, Containers::
     }
 }
 
+/** @todo drop std::string in favor of our own string caster */
+template<class T, bool(Trade::AbstractSceneConverter::*f)(const T&, Containers::StringView)> void checkResult(Trade::AbstractSceneConverter& self, const T& mesh, const std::string& filename) {
+    /** @todo log redirection -- but we'd need assertions to not be part of
+        that so when it dies, the user can still see why */
+    bool out = (self.*f)(mesh, filename);
+    if(!out) {
+        PyErr_SetString(PyExc_RuntimeError, "conversion failed");
+        throw py::error_already_set{};
+    }
+}
+
 }
 
 void trade(py::module_& m) {
@@ -341,6 +353,15 @@ void trade(py::module_& m) {
 
     py::class_<PluginManager::Manager<Trade::AbstractImageConverter>, PluginManager::AbstractManager> imageConverterManager{m, "ImageConverterManager", "Manager for image converter plugins"};
     corrade::manager(imageConverterManager);
+
+    /* Scene converter */
+    py::class_<Trade::AbstractSceneConverter, PluginManager::PyPluginHolder<Trade::AbstractSceneConverter>> abstractSceneConverter{m, "AbstractSceneConverter", "Interface for scene converter plugins"};
+    abstractSceneConverter
+        .def("convert_to_file", checkResult<Trade::MeshData, &Trade::AbstractSceneConverter::convertToFile>, "Convert a mesh to a file", py::arg("mesh"), py::arg("filename"));
+    corrade::plugin(abstractSceneConverter);
+
+    py::class_<PluginManager::Manager<Trade::AbstractSceneConverter>, PluginManager::AbstractManager> sceneConverterManager{m, "SceneConverterManager", "Manager for scene converter plugins"};
+    corrade::manager(sceneConverterManager);
 }
 
 }