gnu: openboardview: Unbundle imgui.

* gnu/packages/patches/openboardview-use-system-imgui.patch: New file.
* gnu/local.mk (dist_patch_DATA): Register it.
* gnu/packages/electronics.scm (openboardview)[source]: Delete "imgui"
subdirectory from snippet and apply patch.
[inputs]{imgui}: New input.

1 files changed, 170 insertions, 0 deletions

diff --git a/gnu/packages/patches/openboardview-use-system-imgui.patch b/gnu/packages/patches/openboardview-use-system-imgui.patch
new file mode 100644
index 0000000000..7345f1fe99
--- /dev/null
+++ b/gnu/packages/patches/openboardview-use-system-imgui.patch
@@ -0,0 +1,170 @@
+Patch submitted upstream: https://github.com/OpenBoardView/OpenBoardView/pull/233
+
+diff --git a/CMakeModules/FindImGui.cmake b/CMakeModules/FindImGui.cmake
+new file mode 100644
+index 0000000..4d1fa42
+--- /dev/null
++++ b/CMakeModules/FindImGui.cmake
+@@ -0,0 +1,36 @@
++# Copyright (C) 2018, 2022 Maxim Cournoyer
++# Redistribution and use of this file is allowed according to the terms of the MIT license.
++# For details see the LICENSE file distributed with OpenBoardView.
++#	Note:
++#		Searching headers and libraries is very simple and is NOT as powerful as scripts
++#		distributed with CMake, because LuaDist defines directories to search for.
++#		Everyone is encouraged to contact the author with improvements. Maybe this file
++#		becomes part of CMake distribution sometimes.
++
++# - Find ImGui
++# Find the native imgui headers and libraries.
++#
++# IMGUI_INCLUDE_DIRS	- where to find imgui/imgui.h, etc.
++# IMGUI_LIBRARIES	- List of libraries when using imgui.
++# IMGUI_FOUND	        - True if imgui is found.
++
++# Look for the header file.
++FIND_PATH(IMGUI_INCLUDE_DIR NAMES imgui.h PATH_SUFFIXES imgui)
++
++# Look for the library.
++FIND_LIBRARY(IMGUI_LIBRARY NAMES ImGui imgui)
++
++# Handle the QUIETLY and REQUIRED arguments and set IMGUI_FOUND to TRUE if all listed variables are TRUE.
++INCLUDE(FindPackageHandleStandardArgs)
++FIND_PACKAGE_HANDLE_STANDARD_ARGS(ImGui DEFAULT_MSG IMGUI_LIBRARY IMGUI_INCLUDE_DIR)
++
++# Copy the results to the output variables.
++IF(IMGUI_FOUND)
++	SET(IMGUI_LIBRARIES ${IMGUI_LIBRARY})
++	SET(IMGUI_INCLUDE_DIRS ${IMGUI_INCLUDE_DIR})
++ELSE()
++	SET(IMGUI_LIBRARIES)
++	SET(IMGUI_INCLUDE_DIRS)
++ENDIF()
++
++MARK_AS_ADVANCED(IMGUI_INCLUDE_DIRS IMGUI_LIBRARIES)
+diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
+index 301f933..24bf263 100644
+--- a/src/CMakeLists.txt
++++ b/src/CMakeLists.txt
+@@ -76,28 +76,30 @@ endif()
+ # note: in the future there may be integrated CMake support into imgui
+ # see: https://github.com/ocornut/imgui/pull/1713
+ # for now do it manually, after glad and SDL2 because we use the includes for the sdl_opengl examples
+-execute_process(
++find_package(ImGui)             # search ImGui from system
++if(NOT IMGUI_FOUND)             # else fallback to bundled copy
++    execute_process(
+ 	COMMAND git submodule update --init src/imgui
+-	WORKING_DIRECTORY ${PROJECT_SOURCE_DIR}
+-)
+-add_definitions("-DImDrawIdx=unsigned int") # short is not enough for us
+-add_definitions("-DIMGUI_IMPL_OPENGL_LOADER_GLAD") # We use glad
+-# Configure GL3 renderer to be GLES2 compatible if GLES2 is enabled
+-if(ENABLE_GLES2)
+-    add_definitions("-DIMGUI_IMPL_OPENGL_ES2")
+-endif()
+-
+-# workaround for OpenGL include for OpenGL2, need to be glad rather than gl itself
+-file(READ "${CMAKE_CURRENT_SOURCE_DIR}/imgui/backends/imgui_impl_opengl2.cpp" input)
+-string(REPLACE "OpenGL/gl.h" "glad/glad.h" input "${input}")
+-string(REPLACE "GL/gl.h" "glad/glad.h" input "${input}")
+-file(WRITE "${CMAKE_CURRENT_SOURCE_DIR}/imgui/backends/imgui_impl_opengl2.cpp" "${input}")
+-
+-include_directories(${CMAKE_CURRENT_SOURCE_DIR}/imgui
+-	${GLAD_INCLUDE_DIRS}
+-)
+-
+-set(SOURCES
++	WORKING_DIRECTORY ${PROJECT_SOURCE_DIR})
++    add_definitions("-DImDrawIdx=unsigned int") # short is not enough for us
++    add_definitions("-DIMGUI_IMPL_OPENGL_LOADER_GLAD") # We use glad
++    # Configure GL3 renderer to be GLES2 compatible if GLES2 is enabled
++    if(ENABLE_GLES2)
++        add_definitions("-DIMGUI_IMPL_OPENGL_ES2")
++    endif()
++
++    # workaround for OpenGL include for OpenGL2, need to be glad rather than gl itself
++    file(READ "${CMAKE_CURRENT_SOURCE_DIR}/imgui/backends/imgui_impl_opengl2.cpp" input)
++    string(REPLACE "OpenGL/gl.h" "glad/glad.h" input "${input}")
++    string(REPLACE "GL/gl.h" "glad/glad.h" input "${input}")
++    file(WRITE "${CMAKE_CURRENT_SOURCE_DIR}/imgui/backends/imgui_impl_opengl2.cpp" "${input}")
++
++    set(IMGUI_INCLUDE_DIRS ${CMAKE_CURRENT_SOURCE_DIR}/imgui
++        ${CMAKE_CURRENT_SOURCE_DIR}/imgui/examples)
++
++    set(IMGUI_LIBRARIES imgui)
++
++    set(SOURCES
+ 	imgui/imgui.cpp
+ 	imgui/imgui_draw.cpp
+ 	imgui/imgui_tables.cpp
+@@ -106,33 +108,35 @@ set(SOURCES
+ 	imgui/backends/imgui_impl_sdl.cpp)
+ 
+ 
+-if(ENABLE_GL1)
++    if(ENABLE_GL1)
+ 	LIST(APPEND SOURCES
+-		imgui/backends/imgui_impl_opengl2.cpp
+-	)
+-endif()
+-if(ENABLE_GL3)
++	    imgui/backends/imgui_impl_opengl2.cpp
++	    )
++    endif()
++    if(ENABLE_GL3)
+ 	LIST(APPEND SOURCES
+-		imgui/backends/imgui_impl_opengl3.cpp
+-	)
+-endif()
++	    imgui/backends/imgui_impl_opengl3.cpp
++	    )
++    endif()
+ 
+-add_library(imgui STATIC ${SOURCES})
+-target_link_libraries(imgui
++    add_library(imgui STATIC ${SOURCES})
++    target_link_libraries(imgui
+ 	${GLAD_LIBRARIES}
+-)
+-if(MINGW)
+-target_link_libraries(imgui
+-	SDL2::SDL2-static
+-)
+-else()
+-target_link_libraries(imgui
+-	SDL2::SDL2
+-)
++        )
++    if(MINGW)
++        target_link_libraries(imgui
++	    SDL2::SDL2-static
++            )
++    else()
++        target_link_libraries(imgui
++	    SDL2::SDL2
++            )
++    endif()
+ endif()
+ 
+-set(IMGUI_INCLUDE_DIRS ${CMAKE_CURRENT_SOURCE_DIR}/imgui ${CMAKE_CURRENT_SOURCE_DIR}/imgui/examples)
+-
++include_directories(
++    ${IMGUI_INCLUDE_DIRS}
++    ${GLAD_INCLUDE_DIRS})
+ 
+ #install(TARGETS imgui DESTINATION ${INSTALL_ARCHIVE_DIR}) # No need to install a static lib
+ 
+diff --git a/src/openboardview/CMakeLists.txt b/src/openboardview/CMakeLists.txt
+index d049ef9..bb56f70 100644
+--- a/src/openboardview/CMakeLists.txt
++++ b/src/openboardview/CMakeLists.txt
+@@ -129,7 +129,7 @@ elseif(APPLE)
+ endif()
+ 
+ target_link_libraries(${PROJECT_NAME_LOWER}
+-	imgui
++	${IMGUI_LIBRARIES}
+ 	SQLite::SQLite3
+ 	${GLAD_LIBRARIES}
+ 	${COCOA_LIBRARY}