Write the icons with qiconmaker at build time

cmake/AddIcon.cmake

@@ -0,0 +1,50 @@
+# SPDX-FileCopyrightText: Team OpenVPI
+# SPDX-License-Identifier: Apache-2.0
+
+# Icons written at build time by qiconmaker (https://github.com/stdware/qiconmaker) from images,
+# so that the repository keeps the images rather than the icon files. The package qiconmaker is
+# found before this file is included.
+
+# Qt Core for the directory of its DLLs, which qiconmaker loads on Windows
+qm_find_qt(Core)
+
+# add_icon(<output> <directory>)
+#
+# Writes the icon <output>, an .ico of Windows or an .icns of macOS by its suffix, from the images
+# <directory>/<size>x<size>.png in a custom command. The image of 1024 px is the master image. A
+# size of the format that has an image of its own takes that image, and qiconmaker reduces the
+# master image to every other size. A target of the same directory that lists <output> as a source
+# builds the icon first, and qm_add_win_rc_enhanced() and qm_add_mac_bundle() of qmsetup accept it.
+function(add_icon _output _directory)
+    set(_master "${_directory}/1024x1024.png")
+    set(_arguments "${_output}" "${_master}")
+    set(_depends "${_master}")
+
+    # The sizes that qiconmaker writes for each format by default
+    if(_output MATCHES "\\.icns$")
+        set(_sizes 16 32 64 128 256 512)
+    else()
+        set(_sizes 16 20 24 30 32 36 40 48 60 64 72 80 96 256)
+    endif()
+
+    foreach(_size IN LISTS _sizes)
+        set(_file "${_directory}/${_size}x${_size}.png")
+        if(EXISTS "${_file}")
+            list(APPEND _arguments "${_size}=${_file}")
+            list(APPEND _depends "${_file}")
+        endif()
+    endforeach()
+
+    # The program loads the DLLs of Qt, which Windows finds through PATH. On the other systems the
+    # program holds the run path to the libraries of Qt.
+    set(_command $<TARGET_FILE:qiconmaker::qiconmaker>)
+    if(WIN32)
+        set(_command ${CMAKE_COMMAND} -E env "PATH=$<TARGET_FILE_DIR:Qt6::Core>" ${_command})
+    endif()
+    add_custom_command(OUTPUT "${_output}"
+        COMMAND ${_command} ${_arguments}
+        DEPENDS ${_depends}
+        COMMENT "Writing ${_output}"
+        VERBATIM
+    )
+endfunction()

scripts/vcpkg-manifest/vcpkg.json

@@ -43,7 +43,11 @@
         },
         "xxhash",
         "signalsmith-dsp",
-        "rubberband"
+        "rubberband",
+        {
+            "name": "qiconmaker",
+            "platform": "windows | osx"
+        }
     ],
     "vcpkg-configuration": {
         "overlay-ports": [

src/app/CMakeLists.txt

@@ -1,40 +1,52 @@
 # SPDX-FileCopyrightText: Team OpenVPI
 # SPDX-License-Identifier: Apache-2.0
 
-add_subdirectory(icons)
-
+# The icons of the application and of the project files, written at build time from the images in
+# icons/<name>. The installer of Windows takes the icon of the project files from the resources of
+# the executable, and the bundle of macOS from its resources. Linux uses the images directly.
 set(_ico_args)
 set(_icns_args)
+set(_icons)
 
-if(WIN32)
-    list(APPEND _ico_path
-        ${CMAKE_CURRENT_BINARY_DIR}/icons/app.ico
-        ${CMAKE_CURRENT_BINARY_DIR}/icons/dspx.ico
-    )
-    set(_filtered_ico_path "")
-    foreach(_file IN LISTS _ico_path)
-        if(EXISTS ${_file})
-            list(APPEND _filtered_ico_path ${_file})
-        endif()
-    endforeach()
-    set(_ico_args ICO ${_filtered_ico_path})
-endif()
+if(WIN32 OR APPLE)
+    find_package(qiconmaker CONFIG REQUIRED)
+    include(${CMAKE_CURRENT_SOURCE_DIR}/../../cmake/AddIcon.cmake)
 
-if(APPLE)
-    set(_icns_path ${CMAKE_CURRENT_BINARY_DIR}/icons/app.icns)
-    if(EXISTS ${_icns_path})
-        set(_icns_args ICNS ${_icns_path})
+    if(WIN32)
+        set(_suffix .ico)
+    else()
+        set(_suffix .icns)
     endif()
-endif()
 
+    foreach(_name IN ITEMS app dspx)
+        set(_icon ${CMAKE_CURRENT_BINARY_DIR}/icons/${_name}${_suffix})
+        add_icon(${_icon} ${CMAKE_CURRENT_SOURCE_DIR}/icons/${_name})
+        list(APPEND _icons ${_icon})
+    endforeach()
 
+    if(WIN32)
+        set(_ico_args ICO ${_icons})
+    else()
+        set(_icns_args ICNS ${CMAKE_CURRENT_BINARY_DIR}/icons/app.icns)
+    endif()
+endif()
 
 ck_configure_application(
     ${_ico_args}
     ${_icns_args}
     INFO_PLIST ${CMAKE_CURRENT_SOURCE_DIR}/info.plist.in
 )
 
+if(_icons)
+    target_sources(${PROJECT_NAME} PRIVATE ${_icons})
+endif()
+
+if(APPLE)
+    set_source_files_properties(${CMAKE_CURRENT_BINARY_DIR}/icons/dspx.icns PROPERTIES
+        MACOSX_PACKAGE_LOCATION Resources
+    )
+endif()
+
 qm_configure_target(${PROJECT_NAME}
     SOURCES main.cpp
     QT_LINKS_PRIVATE
@@ -75,19 +87,12 @@ ck_add_shared_files(
     # SRC conf/${CK_PLATFORM_LOWER}/qtmediate.json DEST ${CK_BUILD_QT_CONF_DIR}   # qtmediate.json
 )
 
-if(EXISTS ${CMAKE_CURRENT_BINARY_DIR}/icons/dspx.icns)
-    ck_add_shared_files(
-        SRC ${CMAKE_CURRENT_BINARY_DIR}/icons/dspx.icns DEST ${CK_BUILD_DATA_DIR}
-    )
-endif()
-
-file(GLOB _icons icons/*)
-list(FILTER _icons EXCLUDE REGEX CMakeLists.txt)
+file(GLOB _icon_images icons/*)
 
 qt_add_resources(${PROJECT_NAME} icons
     PREFIX /diffscope/icons
     BASE icons
-    FILES ${_icons}
+    FILES ${_icon_images}
 )
 
 if(LINUX)