small cleanup

lib/waterfoul/cpu.rb

@@ -100,7 +100,7 @@ module Waterfoul
     # counter (except under particular circumstances, see interrupts)
     def fetch_instruction(no_increment_pc = false)
       instruction_byte = $mmu.read_byte @pc
-      @pc = (@pc + 1) & 0xFFFF unless increment_pc
+      @pc = (@pc + 1) & 0xFFFF unless no_increment_pc
       instruction_byte
     end
 

lib/waterfoul/emulator.rb

@@ -6,8 +6,8 @@ module Waterfoul
       # read the given file as binary and break it down into an array of bytes
       rom = File.binread(rom_filename).bytes
       # initialize emulated CPU, GPU & Scren components
-      cartridge = Cartridge.new rom
       $mmu = MMU.new
+      @cartridge = Cartridge.new rom
       @cpu = CPU.new
       @cpu = SkipBoot.set_state(@cpu) if options.has_key?('skip_boot')
       @gpu = GPU.new
@@ -15,6 +15,7 @@ module Waterfoul
     end
 
     def run
+      $mmu.cartridge = @cartridge
       loop do
         @cpu.step
         @gpu.step @cpu.m

lib/waterfoul/screen.rb

@@ -9,7 +9,7 @@ module Waterfoul
       @buffer = FFI::MemoryPointer.new :uint32, SCREEN_WIDTH * SCREEN_HEIGHT
       @window = SDL.CreateWindow 'waterfoul', 0, 0, SCREEN_WIDTH, SCREEN_HEIGHT, 0
       @renderer = SDL.CreateRenderer @window, -1, 0
-      @texture = SDL.CreateTexture @renderer, SDL::SDL_PIXELFORMAT_ARGB8888, 1, SCREEN_WIDTH, SCREEN_HEIGHT
+      @texture = SDL.CreateTexture @renderer, SDL::PIXELFORMAT_ARGB8888, 1, SCREEN_WIDTH, SCREEN_HEIGHT
     end
 
     def render(framebuffer)

lib/waterfoul/sdl.rb

@@ -9,14 +9,8 @@ module Waterfoul
     INIT_VIDEO = 0x20
     INIT_KEYBOARD = 0x200
     WINDOW_RESIZABLE = 0x20
+    PIXELFORMAT_ARGB8888 = 0x16362004
 
-    SDL_PIXELFORMAT_ARGB8888 =
-      (1 << 28) |
-      (6 << 24) |
-      (3 << 20) |
-      (6 << 16) |
-      (32 << 8) |
-      (4 << 0)
     # keyboard key maps
     SDL_SCANCODE_RETURN = 40 # start
     SDL_SCANCODE_RSHIFT = 229 # select