+ifeq ($(PLATFORM),emscripten)
+SDL_LIBS = -s USE_SDL_IMAGE=2 -s USE_SDL_MIXER=2 -s USE_SDL_NET=2 -s USE_MODPLUG=1 -s USE_MPG123=1 -s USE_ZLIB=1
+SDL_FMTS = -s SDL2_IMAGE_FORMATS='["bmp","png","pcx","xpm"]' -s SDL2_MIXER_FORMATS='["mod","mp3"]'
+EXTRA_CFLAGS = $(SDL_LIBS)
+EXTRA_LDFLAGS = $(SDL_FMTS) -s INITIAL_MEMORY=81920000 -s ALLOW_MEMORY_GROWTH=1 -s FORCE_FILESYSTEM -s NO_EXIT_RUNTIME=0 -s ASYNCIFY -O2 -lidbfs.js
+DATA_DIRS = conf docs levels graphics sounds music
+FILE_PACKAGER_ARGS = --preload $(DATA_DIRS) --js-output=$(DATA_FILE).js
+else