Added a local copy of GLEW

CMakeLists.txt

@@ -248,10 +248,6 @@ endif()
 
 if(RENDERER MATCHES "OpenGL3")
 	target_sources(CSE2 PRIVATE "src/Backends/Rendering/OpenGL3.cpp")
-	find_package(GLEW REQUIRED)
-	target_link_libraries(CSE2 GLEW::GLEW)
-	find_package(OpenGL REQUIRED)
-	target_link_libraries(CSE2 OpenGL::GL)
 elseif(RENDERER MATCHES "Texture")
 	target_sources(CSE2 PRIVATE "src/Backends/Rendering/SDLTexture.cpp")
 elseif(RENDERER MATCHES "Surface")
@@ -408,6 +404,24 @@ else()
 	target_link_libraries(CSE2 freetype)
 endif()
 
+if(RENDERER MATCHES "OpenGL3")
+	if(NOT FORCE_LOCAL_LIBS)
+		find_package(GLEW)
+	endif()
+
+	if(TARGET GLEW::GLEW)
+		message(STATUS "Using system GLEW")
+		target_link_libraries(CSE2 GLEW::GLEW)
+	else()
+		# Compile it ourselves
+		message(STATUS "Using local GLEW")
+		target_sources(CSE2 PRIVATE "external/glew/glew.c" "external/glew/GL/glew.h")
+		target_include_directories(CSE2 PRIVATE "external/glew")
+	endif()
+
+	find_package(OpenGL REQUIRED)
+	target_link_libraries(CSE2 OpenGL::GL)
+endif()
 
 ##
 # DoConfig

README.md

@@ -11,7 +11,7 @@ Cave Story Engine 2 is a decompilation of Cave Story, ported from DirectX to SDL
 * SDL2
 * FreeType
 * FLTK
-* GLEW (if the OpenGL backend is selected) (not currently built with CMake)
+* GLEW (if the OpenGL rendering backend is selected)
 
 ## Building