ChocolateBird/scripts/loaders/SoundLoader.gd

extends Node

signal audio_samples_loaded
signal audio_inst_sample_loaded(id)
signal audio_sfx_sample_loaded(id)
var has_loaded_audio_samples := false

const BGM_NUM := 70
const INST_NUM := 35
const SFX_NUM := 8
const PREPEND_MS := 20  # Prepend 20ms of silence to each sample for preplay purposes
const PLAY_START := PREPEND_MS / 1000.0
const BYTES_PER_SAMPLE := 2  # 16bit samples

const ATTACK_TIME_SMPS := PoolIntArray([131200, 83200, 48000, 32000, 20480, 12160, 8320, 5120, 3072, 2048, 1280, 768, 512, 320, 192, 0])
const ATTACK_TIME_SMPS_ENTRIES := 16
const DECAY_TIME_SMPS := PoolIntArray([38400, 23680, 14080, 9280, 5760, 3520, 2368, 1184])
const DECAY_TIME_SMPS_ENTRIES := 8
const SUSTAIN_DECAY_TIME_SMPS = PoolIntArray([0, 1216000, 896000, 768000, 608000, 448000, 384000, 300800, 227200, 188800, 150400, 112000, 92800, 76800, 57600, 48000, 38400, 28160, 23680, 18880, 14080, 11840, 9280, 7040, 5760, 4800, 3520, 2944, 2368, 1760, 1184, 576])
const SUSTAIN_DECAY_TIME_SMPS_ENTRIES = 32
const SPC_DECAY_CURVE := PoolIntArray([1024, 1020, 1016, 1012, 1008, 1004, 1000, 996, 992, 988, 984, 980, 976, 972, 968, 964, 960, 956, 952, 948, 944, 940, 936, 932, 928, 924, 920, 916, 912, 908, 904, 900, 896, 892, 888, 884, 880, 876, 872, 868, 864, 860, 856, 852, 848, 844, 840, 836, 832, 828, 824, 820, 816, 812, 808, 804, 800, 796, 792, 788, 784, 780, 776, 772, 768, 765, 762, 759, 756, 753, 750, 747, 744, 741, 738, 735, 732, 729, 726, 723, 720, 717, 714, 711, 708, 705, 702, 699, 696, 693, 690, 687, 684, 681, 678, 675, 672, 669, 666, 663, 660, 657, 654, 651, 648, 645, 642, 639, 636, 633, 630, 627, 624, 621, 618, 615, 612, 609, 606, 603, 600, 597, 594, 591, 588, 585, 582, 579, 576, 573, 570, 567, 564, 561, 558, 555, 552, 549, 546, 543, 540, 537, 534, 531, 528, 525, 522, 519, 516, 513, 510, 508, 506, 504, 502, 500, 498, 496, 494, 492, 490, 488, 486, 484, 482, 480, 478, 476, 474, 472, 470, 468, 466, 464, 462, 460, 458, 456, 454, 452, 450, 448, 446, 444, 442, 440, 438, 436, 434, 432, 430, 428, 426, 424, 422, 420, 418, 416, 414, 412, 410, 408, 406, 404, 402, 400, 398, 396, 394, 392, 390, 388, 386, 384, 382, 380, 378, 376, 374, 372, 370, 368, 366, 364, 362, 360, 358, 356, 354, 352, 350, 348, 346, 344, 342, 340, 338, 336, 334, 332, 330, 328, 326, 324, 322, 320, 318, 316, 314, 312, 310, 308, 306, 304, 302, 300, 298, 296, 294, 292, 290, 288, 286, 284, 282, 280, 278, 276, 274, 272, 270, 268, 266, 264, 262, 260, 258, 256, 255, 254, 253, 252, 251, 250, 249, 248, 247, 246, 245, 244, 243, 242, 241, 240, 239, 238, 237, 236, 235, 234, 233, 232, 231, 230, 229, 228, 227, 226, 225, 224, 223, 222, 221, 220, 219, 218, 217, 216, 215, 214, 213, 212, 211, 210, 209, 208, 207, 206, 205, 204, 203, 202, 201, 200, 199, 198, 197, 196, 195, 194, 193, 192, 191, 190, 189, 188, 187, 186, 185, 184, 183, 182, 181, 180, 179, 178, 177, 176, 175, 174, 173, 172, 171, 170, 169, 168, 167, 166, 165, 164, 163, 162, 161, 160, 159, 158, 157, 156, 155, 154, 153, 152, 151, 150, 149, 148, 147, 146, 145, 144, 143, 142, 141, 140, 139, 138, 137, 136, 135, 134, 133, 132, 131, 130, 129, 128, 127, 126, 125, 124, 123, 122, 121, 120, 119, 118, 117, 116, 115, 114, 113, 112, 111, 110, 109, 108, 107, 106, 105, 104, 103, 102, 101, 100, 99, 98, 97, 96, 95, 94, 93, 92, 91, 90, 89, 88, 87, 86, 85, 84, 83, 82, 81, 80, 79, 78, 77, 76, 75, 74, 73, 72, 71, 70, 69, 68, 67, 66, 65, 64, 63, 62, 61, 60, 59, 58, 57, 56, 55, 54, 53, 52, 51, 50, 49, 48, 47, 46, 45, 44, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0, 0])
const SPC_DECAY_CURVE_ENTRIES := 535  # len(SPC_DECAY_CURVE)  # Includes trailing zero

# !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
# !!! Testing a workaround for a Godot 3.x AudioStreamSample playback:                                !!!
# !!! Copy the looped samples one or more times to avoid the break in interpolation at buffer end.    !!!
# !!! Adding a few ms to the loops removes harshness.                                                 !!!
const HACK_EXTEND_LOOP_SAMPLE_EXTRA_MS := 2                                                         # !!!
func HACK_EXTEND_LOOP_SAMPLE(audio: AudioStreamSample) -> AudioStreamSample:                        # !!!
	var output: AudioStreamSample = audio.duplicate(true)                                           # !!!
	# Prepend silence                                                                               # !!!
	var silent_samples := (audio.mix_rate * PREPEND_MS) / 1000                                      # !!!
	var silence := PoolByteArray()                                                                  # !!!
	silence.resize(silent_samples * 2)  # 16bit samples in 8bit array                               # !!!
	silence.fill(0)                                                                                 # !!!
	output.data = silence + output.data                                                             # !!!
	output.loop_begin += silent_samples                                                             # !!!
	output.loop_end += silent_samples                                                               # !!!
	# Append looped samples                                                                         # !!!
	if output.loop_begin >= output.loop_end:                                                        # !!!
		return output                                                                               # !!!
	var looped_samples = audio.data.subarray(audio.loop_begin * BYTES_PER_SAMPLE, -1)               # !!!
	var loop_len = len(looped_samples)                                                              # !!!
	var target_len = (audio.mix_rate * HACK_EXTEND_LOOP_SAMPLE_EXTRA_MS / 1000) * BYTES_PER_SAMPLE  # !!!
	while loop_len < target_len:  # Keep doubling in length until it's long enough                  # !!!
		looped_samples += looped_samples                                                            # !!!
		loop_len = len(looped_samples)                                                              # !!!
	output.data += looped_samples                                                                   # !!!
	return output                                                                                   # !!!
# !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

var bgm_tracks = []
var instrument_samples = []
var instrument_samples_HACK_EXTENDED_LOOPS = []
var sfx_samples = []

var audio_renderer_viewport: Viewport
var audio_renderer: Node


func read_rom_address(buffer: StreamPeerBuffer) -> int:
	# Read a 3-byte little-endian address and wrap the bank to ROM space
	return buffer.get_u16() + ((buffer.get_u8() & 0x3F) << 16)

const MAX_15B = 1 << 15
const MAX_16B = 1 << 16
func unsigned16_to_signed(unsigned):
	return (unsigned + MAX_15B) % MAX_16B - MAX_15B

func get_reference_pitch_samplerate(tuning1: int, tuning2: int = 0) -> int:
	# This is non-trivial and subject to change
	var pitch_scale = tuning1/255.0 + tuning2/65535.0
	if tuning1 < 0x80:
		pitch_scale += 1.0
	return int(pitch_scale * 36000)
	# return (unsigned16_to_signed(pitch) + 0x8000) * 32000/4096

func process_sample(mantissa: int, exponent: int) -> int:
	# For filter arithmetic the samples need to be in signed form.
	# Sign-extend
	if mantissa >= 8:
		mantissa |= 0xFFF0
	if exponent > 12:
		exponent = 12
	var unsigned = (mantissa << exponent) & 0xFFFF
	return unsigned16_to_signed(unsigned)

func clamp_short(i: int) -> int:
	if i < -0x8000:
		return -0x8000
	if i > 0x7FFF:
		return 0x7FFF
	return i

func make_sample(buffer: StreamPeerBuffer, size: int, sample_rate: int) -> AudioStreamSample:
	var audio := AudioStreamSample.new()
	audio.mix_rate = sample_rate
	audio.stereo = false
	audio.set_format(AudioStreamSample.FORMAT_16_BITS)

	if (size % 9) != 0:
		print_debug('Oh no! An instrument sample has an invalid size of %d! at $%06X' % [size, buffer.get_position()-2])
		return audio
	var num_packets := size/9

	var samples = PoolIntArray([0, 0])  # Start with two zero samples for filter purposes, strip them from the actual output later
	var i := 2
	for pkt in num_packets:
		# Decode a single 9byte BRR packet
		var header_byte := buffer.get_u8()
		var exponent := header_byte >> 4
		var filter := (header_byte >> 2) & 0x03
		# var loop := bool(header_byte & 0x02)
		var end := bool(header_byte & 0x01)
		for sample in 8:
			var b := buffer.get_u8()
			samples.append(process_sample(b >> 4, exponent))
			samples.append(process_sample(b & 0x0F, exponent))
		# Apply filter
		var l := len(samples)
		match filter:
			1:
				for j in range(l-16, l):
					samples[j] = clamp_short(samples[j] + (samples[j-1]*15)/16)
			2:
				for j in range(l-16, l):
					samples[j] = clamp_short(samples[j] + (samples[j-1]*61)/32 - (samples[j-2]*15)/16)
			3:
				for j in range(l-16, l):
					samples[j] = clamp_short(samples[j] + (samples[j-1]*115)/64 - (samples[j-2]*13)/16)
		if end:
			# print('End flag on packet')
			break
	# Remove first two zero samples
	samples.remove(0)
	samples.remove(0)
	# Pack 16bit samples to 8bit array
	var out_buff = StreamPeerBuffer.new()
	for sample in samples:
		out_buff.put_16(sample)
	audio.data = out_buff.data_array
	return audio

func get_inst_sample_data(snes_data: Dictionary, buffer: StreamPeerBuffer, id: int) -> AudioStreamSample:
	var sample_rate := get_reference_pitch_samplerate(snes_data.bgm_instrument_samplerates[id] & 0xFF)
	var loop_start_packet: int = snes_data.bgm_instrument_loop_starts[id]/9  # Note that Instrument $1F Steel Guitar has a length of $088B but a loop point of $088D which is 243.22... packets. Luckily it doesn't matter.
	buffer.seek(snes_data.bgm_instrument_brr_pointers[id] & 0x3FFFFF)
	var size := buffer.get_u16()
	var num_samples := (size/9)*16
	var audio := make_sample(buffer, size, sample_rate)
	audio.loop_mode = AudioStreamSample.LOOP_FORWARD
	audio.loop_begin = (loop_start_packet * 16)  # Each 9byte packet is 16 samples
	audio.loop_end = num_samples
	# print_debug('Loaded instrument #%02X with lookup offset $%06X, BRR data offset $%06X, length $%04X (%f packets, %d samples) and loop point %d samples' % [id, lookup_offset, brr_offset, size, size/9.0, num_samples, audio.loop_begin])
	return audio

# const SFX_BRR_START := 0x041E3F + 2  # First two bytes are the length of the block, 0x010E = 270 bytes = 16 BRR packets = 480 samples
func load_sfx_samples_data(snes_data: Dictionary, buffer: StreamPeerBuffer):
	var brr_spc_addrs = []
	var brr_spc_loop_addrs = []
	for two_of_u16 in snes_data.sfx_brr_pointers:
		brr_spc_addrs.append(two_of_u16[0])
		brr_spc_loop_addrs.append(two_of_u16[1])
	var brr_spc_start = Common.SNES_PSX_addresses.sfx_brr_data.SNES - brr_spc_addrs[0]  # Refactor this later - SFX samples start at $4800 in ARAM, right after the SFX tracks
	for i in SFX_NUM:
		buffer.seek(brr_spc_addrs[i] + brr_spc_start)
		# print('Loading sfx sample #%X with BRR data offset $%06X' % [i, buffer.get_position()])
		var sample_rate := get_reference_pitch_samplerate(snes_data.sfx_samplerates[i] & 0xFF)
		var audio := make_sample(buffer, 900, sample_rate)
		var loop_start_packet: int = brr_spc_loop_addrs[i] - brr_spc_addrs[i]
		audio.loop_mode = AudioStreamSample.LOOP_FORWARD
		audio.loop_begin = (loop_start_packet/9) * 16  # Each 9byte packet is 16 samples
		audio.loop_end = (len(audio.data)/2)
		sfx_samples.append(audio)  # Use 900 as a limit, it won't be hit, parser stops after End packet anyway
		emit_signal('audio_sfx_sample_loaded', i)
		# print('size of %d samples' % sfx_samples[i].data.size())


# Called when the node enters the scene tree for the first time.
func load_samples(snes_data: Dictionary, buffer: StreamPeerBuffer):
	load_sfx_samples_data(snes_data, buffer)
	# For some reason, this is a bit slow currently under certain editor conditions. Might optimize later.
	for i in INST_NUM:
		var samp := get_inst_sample_data(snes_data, buffer, i)
		instrument_samples.append(samp)
		# Workaround for Godot 3.x quirk where looping samples are interpolated as if they go to nothing instead of looping
		instrument_samples_HACK_EXTENDED_LOOPS.append(HACK_EXTEND_LOOP_SAMPLE(samp))
		# print('Instrument %02X has mix_rate %d Hz and %d samples'%[i, samp.mix_rate, len(samp.data)/2])
		emit_signal('audio_inst_sample_loaded', i)
		# samp.save_to_wav('output/instrument%02d(%dHz)(loop from %d to %d of %d).wav' % [i, samp.mix_rate, samp.loop_begin, samp.loop_end, len(samp.data)/2])


# We start the texture with a bunch of same-size headers
#     int32  sample_start       // The true start, after the prepended 3 frames of silence
#     uint16 sample_length      // 3 frames after the true end, because of how we loop
#     uint16 sample_loop_begin  // 3 frames after the true loop point
#     uint16 mixrate
var samples_tex: ImageTexture
const TEX_WIDTH := 2048
const FILTER_PAD := 32
func samples_to_texture():
	var num_samples := SFX_NUM + INST_NUM
	var header_length := (num_samples * 5) + TEX_WIDTH  # Use first row for the ADSR tables

	# Create header and unwrapped payload separately first
	var header_buffer := StreamPeerBuffer.new()
	var payload_buffer := StreamPeerBuffer.new()

	# Fill first row with ADSR table
	for i in ATTACK_TIME_SMPS:
		header_buffer.put_u32(i)
	for i in DECAY_TIME_SMPS:
		header_buffer.put_u32(i)
	for i in SUSTAIN_DECAY_TIME_SMPS:
		header_buffer.put_u32(i)
	for i in SPC_DECAY_CURVE:
		header_buffer.put_u16(i)
	var remaining_first_row_texels := TEX_WIDTH - (header_buffer.get_position()/2)
	for i in remaining_first_row_texels:
		header_buffer.put_u16(0)

	# Do instrument headers and data in parallel
	for sample in sfx_samples + instrument_samples:
		var sample_data_start: int = header_length + (payload_buffer.get_position()/2) + FILTER_PAD  # After the prepended silence, in texels (2bytes)
		var loop_begin: int = sample.loop_begin
		var loop_length: int = sample.loop_end - loop_begin
		var nonlooping: bool = loop_length <= 0
		# print('Processing sample, nonlooping=%s'%nonlooping)

		for i in FILTER_PAD:  # Prepend frames of silence
			payload_buffer.put_16(0)
		payload_buffer.put_data(sample.data)  # Copy entire S16LE audio data

		if nonlooping:
			# Append trailing silence for filter safety
			for i in FILTER_PAD*5:
				payload_buffer.put_16(0)
			# Make it loop the trailing silence
			loop_begin += FILTER_PAD
			loop_length = 1
		else:
			# Append copies of the loop for filter safety
			# var loop_data = sample.data.subarray(sample.loop_begin*2, -1)
			# for i in ceil((FILTER_PAD*4)/loop_length):
			# 	payload_buffer.put_data(loop_data)

			# Copy frame by frame in case the loop is shorter than padding frames
			for i in FILTER_PAD*4:
				var pos := payload_buffer.get_position()
				payload_buffer.seek(pos - loop_length*2)
				var frame := payload_buffer.get_16()
				payload_buffer.seek(pos)
				payload_buffer.put_16(frame)
		header_buffer.put_32(sample_data_start)
		header_buffer.put_u16(loop_begin + FILTER_PAD)
		header_buffer.put_u16(loop_length)
		header_buffer.put_u16(sample.mix_rate)
	# Combine the unwrapped arrays
	var data := header_buffer.data_array + payload_buffer.data_array
	var datasamp := AudioStreamSample.new()
	datasamp.data = data
	datasamp.mix_rate = 32000
	datasamp.format = AudioStreamSample.FORMAT_16_BITS
	# datasamp.save_to_wav('output/texture_inst_data.wav')
	var needed_rows := (len(data)/2)/float(TEX_WIDTH)
	var rows := int(pow(2, ceil(log(needed_rows) / log(2))))
	if rows > TEX_WIDTH:
		print_debug('Sound Sample Texture rows have exceeded width: %d > %d'%[rows, TEX_WIDTH])
	# Now that the full texture size is known, pad our existing data with zeroes until the end
	var final_data_size_bytes = rows * TEX_WIDTH * 2
	if final_data_size_bytes > len(data):
		var end_padding := PoolByteArray()
		end_padding.resize(final_data_size_bytes - len(data))
		end_padding.fill(0)
		data = data + end_padding

	# data is complete, turn it into an ImageTexture for the shader to use
	var samples_img = Image.new()
	samples_img.create_from_data(TEX_WIDTH, rows, false, Image.FORMAT_LA8, data)
	self.samples_tex = ImageTexture.new()
	self.samples_tex.create_from_image(samples_img, 0)  #Texture.FLAG_FILTER)


var player := AudioStreamPlayer.new()  # Make one for each channel, later
func play_sample(id: int, pitch_scale: float = 1.0):
	print('Playing inst sample #%02X' % id)
	player.pitch_scale = pitch_scale
	player.stream = instrument_samples_HACK_EXTENDED_LOOPS[id]
	player.play(PLAY_START/pitch_scale)

func play_sfx(id: int):
	print('Playing sfx sample #%02X' % id)
	player.pitch_scale = 1.0
	player.stream = sfx_samples[id]
	player.play(PLAY_START)

func parse_rom(snes_data: Dictionary, buffer: StreamPeerBuffer):
	load_samples(snes_data, buffer)
	#load_bgms(buffer)
	has_loaded_audio_samples = true
	emit_signal('audio_samples_loaded')

func _ready() -> void:
	self.player.name = 'player'  # Easier to see in the debugger
	add_child(self.player)
	audio_renderer_viewport = Viewport.new()
	audio_renderer_viewport.name = 'audio_renderer_viewport'
	audio_renderer_viewport.size_override_stretch = true
	audio_renderer_viewport.transparent_bg = true
	audio_renderer_viewport.handle_input_locally = false
	audio_renderer_viewport.hdr = false
	audio_renderer_viewport.render_target_update_mode = Viewport.UPDATE_ALWAYS
	# add_child(self.audio_renderer_viewport)

	audio_renderer = preload('res://scripts/audio_renderer.gd').new()
	audio_renderer.name = 'audio_renderer'
	audio_renderer_viewport.add_child(audio_renderer)
	get_parent().call_deferred('add_child', audio_renderer_viewport)