#
# Cross Platform Makefile
# Compatible with MSYS2/MINGW, Ubuntu 14.04.1 and Mac OS X
#
# You will need GLFW (http://www.glfw.org):
# Linux:
#   apt-get install libglfw-dev
# Mac OS X:
#   brew install glfw
# MSYS2:
#   pacman -S --noconfirm --needed mingw-w64-x86_64-toolchain mingw-w64-x86_64-glfw
#

#CXX = g++
#CXX = clang++

EXE = example_glfw_opengl3
IMGUI_DIR = ../..
SOURCES = main.cpp
SOURCES += $(IMGUI_DIR)/imgui.cpp $(IMGUI_DIR)/imgui_demo.cpp $(IMGUI_DIR)/imgui_draw.cpp $(IMGUI_DIR)/imgui_tables.cpp $(IMGUI_DIR)/imgui_widgets.cpp
SOURCES += $(IMGUI_DIR)/backends/imgui_impl_glfw.cpp $(IMGUI_DIR)/backends/imgui_impl_opengl3.cpp
OBJS = $(addsuffix .o, $(basename $(notdir $(SOURCES))))
UNAME_S := $(shell uname -s)
LINUX_GL_LIBS = -lGL

CXXFLAGS = -I$(IMGUI_DIR) -I$(IMGUI_DIR)/backends
CXXFLAGS += -g -Wall -Wformat
LIBS =

##---------------------------------------------------------------------
## OPENGL LOADER / OPENGL ES
##---------------------------------------------------------------------

## See below for OpenGL ES option (no loader required) - comment out
## the following if you want to use OpenGL ES instead of Desktop GL.

## Using OpenGL loader: gl3w [default]
SOURCES += ../libs/gl3w/GL/gl3w.c
CXXFLAGS += -I../libs/gl3w -DIMGUI_IMPL_OPENGL_LOADER_GL3W

## Using OpenGL loader: glew
## (This assumes a system-wide installation)
# CXXFLAGS += -DIMGUI_IMPL_OPENGL_LOADER_GLEW
# LIBS += -lGLEW

## Using OpenGL loader: glad
# SOURCES += ../libs/glad/src/glad.c
# CXXFLAGS += -I../libs/glad/include -DIMGUI_IMPL_OPENGL_LOADER_GLAD

## Using OpenGL loader: glad2
# SOURCES += ../libs/glad/src/gl.c
# CXXFLAGS += -I../libs/glad/include -DIMGUI_IMPL_OPENGL_LOADER_GLAD2

## Using OpenGL loader: glbinding
## This assumes a system-wide installation
## of either version 3.0.0 (or newer)
# CXXFLAGS += -DIMGUI_IMPL_OPENGL_LOADER_GLBINDING3
# LIBS += -lglbinding
## or the older version 2.x
# CXXFLAGS += -DIMGUI_IMPL_OPENGL_LOADER_GLBINDING2
# LIBS += -lglbinding

## Using OpenGL ES, no loader required
## This assumes a GL ES library available in the system, e.g. libGLESv2.so
# CXXFLAGS += -DIMGUI_IMPL_OPENGL_ES2
# LINUX_GL_LIBS = -lGLESv2

##---------------------------------------------------------------------
## BUILD FLAGS PER PLATFORM
##---------------------------------------------------------------------

ifeq ($(UNAME_S), Linux) #LINUX
	ECHO_MESSAGE = "Linux"
	LIBS += $(LINUX_GL_LIBS) `pkg-config --static --libs glfw3`

	CXXFLAGS += `pkg-config --cflags glfw3`
	CFLAGS = $(CXXFLAGS)
endif

ifeq ($(UNAME_S), Darwin) #APPLE
	ECHO_MESSAGE = "Mac OS X"
	LIBS += -framework OpenGL -framework Cocoa -framework IOKit -framework CoreVideo
	LIBS += -L/usr/local/lib -L/opt/local/lib -L/opt/homebrew/lib
	#LIBS += -lglfw3
	LIBS += -lglfw

	CXXFLAGS += -I/usr/local/include -I/opt/local/include -I/opt/homebrew/include
	CFLAGS = $(CXXFLAGS)
endif

ifeq ($(OS), Windows_NT)
	ECHO_MESSAGE = "MinGW"
	LIBS += -lglfw3 -lgdi32 -lopengl32 -limm32

	CXXFLAGS += `pkg-config --cflags glfw3`
	CFLAGS = $(CXXFLAGS)
endif

##---------------------------------------------------------------------
## BUILD RULES
##---------------------------------------------------------------------

%.o:%.cpp
	$(CXX) $(CXXFLAGS) -c -o $@ $<

%.o:$(IMGUI_DIR)/%.cpp
	$(CXX) $(CXXFLAGS) -c -o $@ $<

%.o:$(IMGUI_DIR)/backends/%.cpp
	$(CXX) $(CXXFLAGS) -c -o $@ $<

%.o:../libs/gl3w/GL/%.c
	$(CC) $(CFLAGS) -c -o $@ $<

%.o:../libs/glad/src/%.c
	$(CC) $(CFLAGS) -c -o $@ $<

all: $(EXE)
	@echo Build complete for $(ECHO_MESSAGE)

$(EXE): $(OBJS)
	$(CXX) -o $@ $^ $(CXXFLAGS) $(LIBS)

clean:
	rm -f $(EXE) $(OBJS)