Makefile.emscripten

#
# Makefile to use with emscripten
# See https://emscripten.org/docs/getting_started/downloads.html
# for installation instructions.
#
# This Makefile assumes you have loaded emscripten's environment.
# (On Windows, you may need to execute emsdk_env.bat or encmdprompt.bat ahead)
#
# Running `make` will produce three files:
#  - nightingale_emscripten.html
#  - nightingale_emscripten.js
#  - nightingale_emscripten.wasm
#
# All three are needed to run the program.

CC = emcc
CXX = em++
EXE = nightingale_emscripten.html
SOURCES = main_emscripten.cpp app.cpp audio.cpp widgets.cpp
SOURCES += imgui/imgui_impl_sdl.cpp imgui/imgui_impl_opengl3.cpp
SOURCES += imgui/imgui.cpp imgui/imgui_demo.cpp imgui/imgui_draw.cpp imgui/imgui_widgets.cpp imgui/imgui_tables.cpp
SOURCES += imgui/imguihelper.cpp imgui/imgui_plot.cpp imgui/imguifilesystem.cpp
OBJS = $(addsuffix .o, $(basename $(notdir $(SOURCES))))
UNAME_S := $(shell uname -s)

##---------------------------------------------------------------------
## EMSCRIPTEN OPTIONS
##---------------------------------------------------------------------

EMS += -s USE_SDL=2 -s WASM=1
EMS += -s ALLOW_MEMORY_GROWTH=1
EMS += -s DISABLE_EXCEPTION_CATCHING=1 -s NO_EXIT_RUNTIME=0
EMS += -s ASSERTIONS=1

# Uncomment next line to fix possible rendering bugs with Emscripten version older then 1.39.0 (https://github.com/ocornut/imgui/issues/2877)
#EMS += -s BINARYEN_TRAP_MODE=clamp
#EMS += -s SAFE_HEAP=1    ## Adds overhead

# Emscripten allows preloading a file or folder to be accessible at runtime.
# The Makefile for this project suggests embedding the fonts folder into our application, it will then be accessible as "/fonts"
# See documentation for more details: https://emscripten.org/docs/porting/files/packaging_files.html
# (Default value is 0. Set to 1 to enable file-system and include the misc/fonts/ folder as part of the build.)
USE_FILE_SYSTEM ?= 0
ifeq ($(USE_FILE_SYSTEM), 0)
EMS += -s NO_FILESYSTEM=1 -DIMGUI_DISABLE_FILE_FUNCTIONS -DNO_IMGUIHELPER_SERIALIZATION
endif
ifeq ($(USE_FILE_SYSTEM), 1)
LDFLAGS += --no-heap-copy --preload-file fonts@/fonts
endif

##---------------------------------------------------------------------
## FINAL BUILD FLAGS
##---------------------------------------------------------------------

CPPFLAGS += -I. -I./imgui
#CPPFLAGS += -g
CPPFLAGS += -Wall -Wformat -Os
CPPFLAGS += $(EMS)
LIBS += $(EMS)
LDFLAGS += --shell-file shell_minimal.html

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

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

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

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

all: $(EXE)
	@echo Platform is $(UNAME_S)
	@echo Build complete for $(EXE)

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

clean:
	rm -f $(EXE) $(OBJS) *.js *.wasm *.wasm.pre