Class: Doom::Wad::SoundManager

Inherits:
Object
  • Object
show all
Defined in:
lib/doom/wad/sound.rb

Overview

Loads DOOM sound effects from WAD and converts to WAV for Gosu playback. DOOM sound format: 8-byte header (2 format, 2 sample_rate, 4 num_samples) followed by unsigned 8-bit PCM samples.

Instance Method Summary collapse

Constructor Details

#initialize(wad) ⇒ SoundManager

Returns a new instance of SoundManager.



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# File 'lib/doom/wad/sound.rb', line 12

def initialize(wad)
  @wad = wad
  @cache = {} # name => Gosu::Sample
  @temp_dir = File.join(Dir.tmpdir, "doom_rb_sounds_#{Process.pid}")
  Dir.mkdir(@temp_dir) unless Dir.exist?(@temp_dir)

  # Sounds are decoded into a per-process temp dir; clean it up when the
  # process exits so repeated runs do not leak WAV files.
  at_exit { cleanup }
end

Instance Method Details

#[](name) ⇒ Object

Get or load a sound effect. Returns a Gosu::Sample or nil.



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# File 'lib/doom/wad/sound.rb', line 24

def [](name)
  return @cache[name] if @cache.key?(name)

  lump_name = name.start_with?('DS') ? name : "DS#{name}"
  entry = @wad.find_lump(lump_name)
  return @cache[name] = nil unless entry

  data = @wad.read_lump_at(entry)
  return @cache[name] = nil if data.size < 8

  # Parse DOOM sound header
  _format = data[0, 2].unpack1('v')
  sample_rate = data[2, 2].unpack1('v')
  num_samples = data[4, 4].unpack1('V')

  # PCM data starts at offset 8, skip 16 padding bytes at start and end
  pcm_start = 8 + 16
  pcm_end = 8 + num_samples - 16
  pcm_data = data[pcm_start...pcm_end]
  return @cache[name] = nil unless pcm_data && pcm_data.size > 0

  # Convert to WAV file for Gosu
  wav_path = File.join(@temp_dir, "#{lump_name}.wav")
  write_wav(wav_path, pcm_data, sample_rate) unless File.exist?(wav_path)

  @cache[name] = Gosu::Sample.new(wav_path)
rescue StandardError => e
  # A bad or unplayable lump should silence that one sound, not crash the
  # game -- but say so rather than swallowing the error entirely.
  warn "SoundManager: could not load '#{name}': #{e.class}: #{e.message}"
  @cache[name] = nil
end

#cleanup ⇒ Object 



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# File 'lib/doom/wad/sound.rb', line 57

def cleanup
  FileUtils.rm_rf(@temp_dir) if @temp_dir && Dir.exist?(@temp_dir)
end