CMake: add a possibility to link static plugins to utility executables.

Funny/sad that this possibility took me so long to realize. Until now it
was "you can have command-line utilities or static plugins but never
both", and only with CMake 3.13+ it was possible to link static plugins
to these executables from outside. Now it's a builtin and supported
option.

CMakeLists.txt

@@ -157,6 +157,9 @@ endif()
 if(CORRADE_TARGET_UNIX OR CORRADE_TARGET_WINDOWS)
     option(MAGNUM_WITH_FONTCONVERTER "Build magnum-fontconverter utility" OFF)
     option(MAGNUM_WITH_DISTANCEFIELDCONVERTER "Build magnum-distancefieldconverter utility" OFF)
+
+    set(MAGNUM_FONTCONVERTER_STATIC_PLUGINS "" CACHE STRING "Static plugins to link to the magnum-fontconverter utility")
+    set(MAGNUM_DISTANCEFIELDCONVERTER_STATIC_PLUGINS "" CACHE STRING "Static plugins to link to the magnum-distancefieldconverter utility")
 endif()
 
 # API-independent utilities
@@ -164,6 +167,10 @@ option(MAGNUM_WITH_IMAGECONVERTER "Build magnum-imageconverter utility" OFF)
 option(MAGNUM_WITH_SCENECONVERTER "Build magnum-sceneconverter utility" OFF)
 option(MAGNUM_WITH_SHADERCONVERTER "Build magnum-shaderconverter utility" OFF)
 
+set(MAGNUM_IMAGECONVERTER_STATIC_PLUGINS "" CACHE STRING "Static plugins to link to the magnum-imageconverter utility")
+set(MAGNUM_SCENECONVERTER_STATIC_PLUGINS "" CACHE STRING "Static plugins to link to the magnum-sceneconverter utility")
+set(MAGNUM_SHADERCONVERTER_STATIC_PLUGINS "" CACHE STRING "Static plugins to link to the magnum-shaderconverter utility")
+
 # Magnum AL Info
 option(MAGNUM_WITH_AL_INFO "Build magnum-al-info utility" OFF)
 

doc/building.dox

@@ -674,6 +674,22 @@ Options controlling the build:
     update your code whenever there's a breaking API change. It's however
     recommended to have this option disabled when deploying a final application
     as it can result in smaller binaries.
+-   `MAGNUM_DISTANCEFIELDCONVERTER_STATIC_PLUGINS`,
+    `MAGNUM_FONTCONVERTER_STATIC_PLUGINS`,
+    `MAGNUM_IMAGECONVERTER_STATIC_PLUGINS`,
+    `MAGNUM_SCENECONVERTER_STATIC_PLUGINS` and
+    `MAGNUM_SHADERCONVERTER_STATIC_PLUGINS` --- Static plugins to link to the
+    @ref magnum-distancefieldconverter "magnum-distancefieldconverter",
+    @ref magnum-fontconverter "magnum-fontconverter",
+    @ref magnum-imageconverter "magnum-imageconverter",
+    @ref magnum-sceneconverter "magnum-sceneconverter" and
+    @ref magnum-shaderconverter "magnum-shaderconverter" utilities,
+    respectively. Intended for use in scenarios where both
+    `MAGNUM_BUILD_STATIC` and `MAGNUM_BUILD_PLUGINS_STATIC` is enabled, in
+    which case these executables don't have a possibility to load dynamic
+    plugins from a filesystem. Plugins from the Magnum Plugins repository
+    (and elsewhere) can be linked if it's added as a CMake subproject. Expects
+    a semicolon-separated list of existing CMake targets, for example `Magnum::AnyImageImporter;MagnumPlugins::StbImageImporter`.
 -   Additional options are inherited from the @ref CORRADE_BUILD_MULTITHREADED,
     @ref CORRADE_BUILD_CPU_RUNTIME_DISPATCH and @ref CORRADE_CPU_USE_IFUNC
     options specified when building Corrade.

doc/changelog.dox

@@ -672,6 +672,13 @@ See also:
     [mosra/magnum#570](https://github.com/mosra/magnum/pull/570).
 -   Fixed wrong `.gitattributes` option for LF line endings in MSYS PKGBUILDs
     (see [mosra/magnum#574](https://github.com/mosra/magnum/issues/574))
+-   Added `MAGNUM_DISTANCEFIELDCONVERTER_STATIC_PLUGINS`,
+    `MAGNUM_FONTCONVERTER_STATIC_PLUGINS`,
+    `MAGNUM_IMAGECONVERTER_STATIC_PLUGINS`,
+    `MAGNUM_SCENECONVERTER_STATIC_PLUGINS` and
+    `MAGNUM_SHADERCONVERTER_STATIC_PLUGINS` CMake options for linking static
+    plugins to the command-line utilities. See @ref building-features for more
+    information.
 
 @subsection changelog-latest-bugfixes Bug fixes
 

src/Magnum/SceneTools/CMakeLists.txt

@@ -27,6 +27,17 @@
 # property that would have to be set on each target separately.
 set(CMAKE_FOLDER "Magnum/SceneTools")
 
+# Somehow, due to MagnumTradeObjects having target_include_directories() with
+# $<TARGET_PROPERTY:Corrade::PluginManager,INTERFACE_INCLUDE_DIRECTORIES>,
+# if MAGNUM_SCENECONVERTER_STATIC_PLUGINS is non-empty then CMake fails with
+#
+#   Target "Corrade::PluginManager" not found.
+#
+# unless the find_package() is here. Not sure why, probably some bug in CMake
+# dependency handling? Changing target_include_directories() to PRIVATE doesn't
+# help, removing it altogether helps.
+find_package(Corrade REQUIRED PluginManager)
+
 # Files shared between main library and unit test library
 set(MagnumSceneTools_SRCS )
 
@@ -88,7 +99,8 @@ if(MAGNUM_WITH_SCENECONVERTER)
         Magnum
         MagnumMeshTools
         MagnumSceneTools
-        MagnumTrade)
+        MagnumTrade
+        ${MAGNUM_SCENECONVERTER_STATIC_PLUGINS})
 
     install(TARGETS magnum-sceneconverter DESTINATION ${MAGNUM_BINARY_INSTALL_DIR})
 

src/Magnum/ShaderTools/CMakeLists.txt

@@ -91,7 +91,8 @@ if(MAGNUM_WITH_SHADERCONVERTER)
     add_executable(magnum-shaderconverter shaderconverter.cpp)
     target_link_libraries(magnum-shaderconverter PRIVATE
         Magnum
-        MagnumShaderTools)
+        MagnumShaderTools
+        ${MAGNUM_SHADERCONVERTER_STATIC_PLUGINS})
 
     install(TARGETS magnum-shaderconverter DESTINATION ${MAGNUM_BINARY_INSTALL_DIR})
 

src/Magnum/Text/CMakeLists.txt

@@ -116,7 +116,8 @@ if(MAGNUM_WITH_FONTCONVERTER)
     target_link_libraries(magnum-fontconverter PRIVATE
         Magnum
         MagnumText
-        MagnumTrade)
+        MagnumTrade
+        ${MAGNUM_FONTCONVERTER_STATIC_PLUGINS})
     if(MAGNUM_TARGET_EGL)
         target_link_libraries(magnum-fontconverter PRIVATE MagnumWindowlessEglApplication)
     elseif(CORRADE_TARGET_IOS)

src/Magnum/TextureTools/CMakeLists.txt

@@ -27,6 +27,18 @@
 # property that would have to be set on each target separately.
 set(CMAKE_FOLDER "Magnum/TextureTools")
 
+# Somehow, due to MagnumTradeObjects having target_include_directories() with
+# $<TARGET_PROPERTY:Corrade::PluginManager,INTERFACE_INCLUDE_DIRECTORIES>,
+# if MAGNUM_DISTANCEFIELDCONVERTER_STATIC_PLUGINS is non-empty then CMake fails
+# with
+#
+#   Target "Corrade::PluginManager" not found.
+#
+# unless the find_package() is here. Not sure why, probably some bug in CMake
+# dependency handling? Changing target_include_directories() to PRIVATE doesn't
+# help, removing it altogether helps.
+find_package(Corrade REQUIRED PluginManager)
+
 set(MagnumTextureTools_GracefulAssert_SRCS
     Atlas.cpp)
 
@@ -84,7 +96,8 @@ if(MAGNUM_WITH_DISTANCEFIELDCONVERTER)
     target_link_libraries(magnum-distancefieldconverter PRIVATE
         Magnum
         MagnumTextureTools
-        MagnumTrade)
+        MagnumTrade
+        ${MAGNUM_DISTANCEFIELDCONVERTER_STATIC_PLUGINS})
     if(MAGNUM_TARGET_EGL)
         target_link_libraries(magnum-distancefieldconverter PRIVATE MagnumWindowlessEglApplication)
     elseif(CORRADE_TARGET_IOS)

src/Magnum/Trade/CMakeLists.txt

@@ -160,7 +160,8 @@ if(MAGNUM_WITH_IMAGECONVERTER)
         MagnumTrade
         # BasisImageConverter uses these, and linking pthread to just the
         # plugin doesn't work. See its documentation for details.
-        Threads::Threads)
+        Threads::Threads
+        ${MAGNUM_IMAGECONVERTER_STATIC_PLUGINS})
 
     install(TARGETS magnum-imageconverter DESTINATION ${MAGNUM_BINARY_INSTALL_DIR})