Examples: Added Makefile for SDL+OpenGL2 example. (#1668)

examples/sdl_opengl2_example/Makefile

@@ -0,0 +1,66 @@
+#
+# Cross Platform Makefile
+# Compatible with MSYS2/MINGW, Ubuntu 14.04.1 and Mac OS X
+#
+# You will need SDL2 (http://www.libsdl.org):
+# Linux:
+#   apt-get install libsdl2-dev
+# Mac OS X:
+#   brew install sdl2
+# MSYS2:
+#   pacman -S mingw-w64-i686-SDL
+#
+
+#CXX = g++
+#CXX = clang++
+
+EXE = sdl_opengl2_example
+SOURCES = main.cpp imgui_impl_sdl_gl2.cpp
+SOURCES += ../../imgui.cpp ../../imgui_demo.cpp ../../imgui_draw.cpp
+OBJS = $(addsuffix .o, $(basename $(notdir $(SOURCES))))
+
+UNAME_S := $(shell uname -s)
+
+
+ifeq ($(UNAME_S), Linux) #LINUX
+	ECHO_MESSAGE = "Linux"
+	LIBS = -lGL -ldl `sdl2-config --libs`
+
+	CXXFLAGS = -I../../  `sdl2-config --cflags`
+	CXXFLAGS += -Wall -Wformat
+	CFLAGS = $(CXXFLAGS)
+endif
+
+ifeq ($(UNAME_S), Darwin) #APPLE
+	ECHO_MESSAGE = "Mac OS X"
+	LIBS = -framework OpenGL -framework Cocoa -framework IOKit -framework CoreVideo `sdl2-config --libs`
+
+	CXXFLAGS = -I../../ -I/usr/local/include `sdl2-config --cflags`
+	CXXFLAGS += -Wall -Wformat
+	CFLAGS = $(CXXFLAGS)
+endif
+
+ifeq ($(findstring MINGW,$(UNAME_S)),MINGW)
+   ECHO_MESSAGE = "Windows"
+   LIBS = -lgdi32 -lopengl32 -limm32 `pkg-config --static --libs sdl2`
+
+   CXXFLAGS = -I../../ `pkg-config --cflags sdl2`
+   CXXFLAGS += -Wall -Wformat
+   CFLAGS = $(CXXFLAGS)
+endif
+
+
+%.o:%.cpp
+	$(CXX) $(CXXFLAGS) -c -o $@ $<
+
+%.o:../../%.cpp
+	$(CXX) $(CXXFLAGS) -c -o $@ $<
+
+all: $(EXE)
+	@echo Build complete for $(ECHO_MESSAGE)
+
+$(EXE): $(OBJS)
+	$(CXX) -o $@ $^ $(CXXFLAGS) $(LIBS)
+
+clean:
+	rm -f $(EXE) $(OBJS)