TARGET_EXEC := sim

BUILD_DIR := ./build
SRC_DIR := ./src
SHADER_DIR := ./shaders

# Find all the C and C++ files we want to compile
SRCS := $(shell find $(SRC_DIR) -name '*.cpp')
GLSLS := $(shell find $(SHADER_DIR) -name '*.glsl')

# Prepends BUILD_DIR and appends .o to every src file
OBJS := $(SRCS:%=$(BUILD_DIR)/%.o)
SPIRVS := $(GLSLS:%.glsl=$(BUILD_DIR)/%.sphv)

# String substitution (suffix version without %).
DEPS := $(OBJS:.o=.d)

# Every folder in ./src will need to be passed to GCC so that it can find header files
INC_DIRS := $(shell find $(SRC_DIRS) -type d)
# Add a prefix to INC_DIRS. So moduleA would become -ImoduleA. GCC understands this -I flag
INC_FLAGS := $(addprefix -I,$(INC_DIRS))


# The -MMD and -MP flags together generate Makefiles for us!
CPPFLAGS := $(INC_FLAGS) -MMD -MP



# The final build step.
$(BUILD_DIR)/$(TARGET_EXEC): $(OBJS)
	$(CXX) $(OBJS) -o $@ $(LDFLAGS)

# Build step for C++ source
$(BUILD_DIR)/%.cpp.o: %.cpp $(SPIRVS) .simdb
    mkdir -p $(dir $@)
    $(CXX) $(CPPFLAGS) $(CXXFLAGS) -c $< -o $i@

#build the shaders
$(SPIRVS): $(GLSL)
    mkdir -p $(dir $@)
    glslc $(shaders).glsl $(shaders).spv


run: $(BUILD_DIR)/$(TARGET_EXEC)
    ./$(BUILD_DIR)/$(TARGET_EXEC)