ifeq ($(ruby),)
  ifeq ($(platform),windows)
    ruby += video.wgl video.direct3d video.directdraw video.gdi
    ruby += audio.asio audio.wasapi audio.xaudio2 audio.directsound audio.waveout
    ruby += input.windows
  else ifeq ($(platform),macos)
    ruby += video.cgl
    ruby += audio.openal
    ruby += input.quartz #input.carbon
  else ifeq ($(platform),linux)
    ruby += video.glx video.glx2 video.xvideo video.xshm
    ruby += audio.oss audio.alsa audio.openal audio.pulseaudio audio.pulseaudiosimple audio.ao
    ruby += input.sdl input.xlib input.udev
  else ifeq ($(platform),bsd)
    ruby += video.glx video.glx2 video.xvideo video.xshm
    ruby += audio.oss audio.openal #audio.pulseaudio
    ruby += input.sdl input.xlib
  endif
endif

ifeq ($(platform),macos)
  ruby.flags := $(flags.objcpp)
else
  ruby.flags := $(flags.cpp)
endif

ruby.flags += $(foreach c,$(subst .,_,$(call strupper,$(ruby))),-D$c)
ruby.flags += $(if $(findstring input.sdl,$(ruby)),$(shell sdl2-config --cflags))

ruby.options :=

ruby.options += $(if $(findstring video.cgl,$(ruby)),-framework OpenGL)
ruby.options += $(if $(findstring video.direct3d,$(ruby)),-ld3d9)
ruby.options += $(if $(findstring video.directdraw,$(ruby)),-lddraw)
ruby.options += $(if $(findstring video.glx,$(ruby)),-lGL)
ruby.options += $(if $(findstring video.wgl,$(ruby)),-lopengl32)
ruby.options += $(if $(findstring video.xvideo,$(ruby)),-lXv)

ruby.options += $(if $(findstring audio.alsa,$(ruby)),-lasound)
ruby.options += $(if $(findstring audio.ao,$(ruby)),-lao)
ruby.options += $(if $(findstring audio.directsound,$(ruby)),-ldsound -luuid)
ruby.options += $(if $(findstring audio.pulseaudio,$(ruby)),-lpulse)
ruby.options += $(if $(findstring audio.pulseaudiosimple,$(ruby)),-lpulse-simple)
ruby.options += $(if $(findstring audio.wasapi,$(ruby)),-lavrt -luuid)
ruby.options += $(if $(findstring audio.waveout,$(ruby)),-lwinmm)
ruby.options += $(if $(findstring audio.xaudio2,$(ruby)),-lole32)

ruby.options += $(if $(findstring input.sdl,$(ruby)),$(shell sdl2-config --libs))
ruby.options += $(if $(findstring input.udev,$(ruby)),-ludev)
ruby.options += $(if $(findstring input.windows,$(ruby)),-ldinput8 -ldxguid)

ifeq ($(platform),windows)
  ruby.options += $(if $(findstring audio.openal,$(ruby)),-lopenal32)
endif

ifeq ($(platform),macos)
  ruby.options += -framework IOKit
  ruby.options += $(if $(findstring audio.openal,$(ruby)),-framework OpenAL)
endif

ifeq ($(platform),linux)
  ruby.options += -lX11 -lXext -lXrandr
  ruby.options += $(if $(findstring audio.openal,$(ruby)),-lopenal)
endif

ifeq ($(platform),bsd)
  ruby.options += -lX11 -lXext -lXrandr
  ruby.options += $(if $(findstring audio.openal,$(ruby)),-lopenal -fuse-ld=bfd)
  # -fuse-ld=bfd: see FreeBSD bug 219089
endif

ruby.objects := $(object.path)/ruby.o

$(object.path)/ruby.o: $(ruby.path)/ruby.cpp $(call rwildcard,$(ruby.path))
	$(info Compiling $< ...)
	@$(compiler) $(ruby.flags) $(flags) $(flags.deps) -c $< -o $@

ruby.verbose:
	$(info ruby Drivers:)
	$(foreach n,$(ruby),$(info $([space]) $n))