From a79115599b7941cddb3f3b336cc1ad0e5bfc3efa Mon Sep 17 00:00:00 2001
From: Gyusun Yeom <omniavinco@gmail.com>
Date: Tue, 29 Dec 2020 22:56:02 +0900
Subject: [PATCH] Modernize cmake

---
 CMakeLists.txt | 72 +++++++++++++++++++++++++++++++++-----------------
 1 file changed, 48 insertions(+), 24 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index e5cd426..5bfdcb2 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -14,7 +14,7 @@ include("GeneratePkgConfig.cmake")
 option(glew-cmake_BUILD_SHARED "Build the shared glew library" ON)
 option(glew-cmake_BUILD_STATIC "Build the static glew library" ON)
 option(USE_GLU "Use GLU" OFF)
-option(PKG_CONFIG_REPRESENTATIVE_TARGET "Generate pc file for specified target as glew. libglew_static|libglewmx_static|libglew_shared|libglewmx_shared" OFF)
+option(PKG_CONFIG_REPRESENTATIVE_TARGET "Generate pc file for specified target as glew. libglew_static|libglew_shared" OFF)
 option(ONLY_LIBS "Do not build executables" OFF)
 
 file(STRINGS ${CMAKE_CURRENT_SOURCE_DIR}/config/version  _VERSION_MAJOR_STRING REGEX "GLEW_MAJOR[ ]*=[ ]*[0-9]+.*")
@@ -36,31 +36,56 @@ if(MSVC)
 	list(APPEND LIBGLEW_SRCS ${RC_DIR}/glew.rc)
 endif()
 
+# Use namespaced libraries when supported
+if(${CMAKE_VERSION} VERSION_GREATER 3.14)
+	set(USE_NAMESPACED_LIB YES)
+else()
+	set(USE_NAMESPACED_LIB NO)
+endif()
+
 if(POLICY CMP0072)
-	set(OpenGL_GL_PREFERENCE LEGACY)
+	set(OpenGL_GL_PREFERENCE GLVND)
 endif()
 
 find_package(OpenGL REQUIRED)
 
+set(pc_requires)
+
 if(NOT USE_GLU)
 	list(APPEND DEFINITIONS -DGLEW_NO_GLU)
-	set(pc_requires)
 else()
-	set(pc_requires REQUIRES glu)
-	list(APPEND LIBRARIES OpenGL::GLU)
 	if(NOT OPENGL_GLU_FOUND)
 		message(FATAL_ERROR "GLU is not found. but GLU option is enabled")
 	endif()
-endif( )
 
-if(WIN32)
-	list(APPEND LIBRARIES opengl32)
-elseif(APPLE)
-	find_library(GL_LIBRARY OpenGL)
-	find_library(AGL_LIBRARY AGL)
-	list(APPEND LIBRARIES ${GL_LIBRARY} ${AGL_LIBRARY})
+	list(APPEND pc_requires glu)
+
+	if(USE_NAMESPACED_LIB)
+		list(APPEND LIBRARIES OpenGL::GLU)
+	else()
+		list(APPEND LIBRARIES OPENGL_glu_LIBRARY)
+	endif()
+endif()
+
+list(APPEND pc_requires gl)
+if(USE_NAMESPACED_LIB)
+	list(APPEND LIBRARIES OpenGL::GL)
 else()
-	list(APPEND LIBRARIES GL X11 dl Xext)
+	list(APPEND LIBRARIES OPENGL_opengl_LIBRARY)
+endif()
+
+if(APPLE)
+	find_library(AGL_LIBRARY AGL)
+	list(APPEND LIBRARIES ${AGL_LIBRARY})
+elseif(NOT WIN32)
+	find_package(X11 REQUIRED)
+
+	list(APPEND pc_requires x11 xext)
+	if(USE_NAMESPACED_LIB)
+		list(APPEND LIBRARIES X11::X11 X11::Xext)
+	else()
+		list(APPEND LIBRARIES X11_X11_LIB X11_Xext_LIB)
+	endif()
 endif()
 
 set(GLEW_TARGETS)
@@ -72,10 +97,7 @@ if(glew-cmake_BUILD_STATIC)
 		OUTPUT_NAME "glew"
 		DEBUG_POSTFIX d)
 
-	target_include_directories(libglew_static PUBLIC ${INCLUDE_DIR})
-	target_compile_definitions(libglew_static PUBLIC GLEW_STATIC ${DEFINITIONS})
-	target_link_libraries(libglew_static ${LIBRARIES} )
-	set_target_properties(libglew_static PROPERTIES VERSION ${GLEW_VERSION})
+		target_compile_definitions(libglew_static PUBLIC GLEW_STATIC)
 	list(APPEND GLEW_TARGETS libglew_static)
 endif()
 
@@ -92,20 +114,22 @@ if(glew-cmake_BUILD_SHARED)
 			DEBUG_POSTFIX d)
 	endif()
 
-	target_compile_definitions(libglew_shared PRIVATE GLEW_BUILD ${DEFINITIONS})
-	target_include_directories(libglew_shared PUBLIC ${INCLUDE_DIR})
-	target_link_libraries(libglew_shared ${LIBRARIES})
-	set_target_properties(libglew_shared PROPERTIES VERSION ${GLEW_VERSION})
+	target_compile_definitions(libglew_shared PRIVATE GLEW_BUILD)
 	list(APPEND GLEW_TARGETS libglew_shared)
 endif()
 
+foreach(GLEW_TARGET ${GLEW_TARGETS})
+	target_compile_definitions(${GLEW_TARGET} PUBLIC ${DEFINITIONS})
+	target_include_directories(${GLEW_TARGET} PUBLIC ${INCLUDE_DIR})
+	target_link_libraries(${GLEW_TARGET} ${LIBRARIES})
+	set_target_properties(${GLEW_TARGET} PROPERTIES VERSION ${GLEW_VERSION})
+endforeach()
+
 if(PKG_CONFIG_REPRESENTATIVE_TARGET)
 	GeneratePkgConfigFile(${PKG_CONFIG_REPRESENTATIVE_TARGET} "The OpenGL Extension Wrangler library"
 		NAME "glew"
 		LIBRARY_DIR lib
-		${pc_requires})
-	add_library(glew ALIAS ${PKG_CONFIG_REPRESENTATIVE_TARGET})
-	list(APPEND GLEW_TARGETS glew)
+		REQUIRES ${pc_requires})
 endif()
 
 install(TARGETS ${GLEW_TARGETS}