src/gba/extra/audio-mixer.c (view raw)
1/* Copyright (c) 2013-2017 Jeffrey Pfau
2 *
3 * This Source Code Form is subject to the terms of the Mozilla Public
4 * License, v. 2.0. If a copy of the MPL was not distributed with this
5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6#include <mgba/internal/gba/extra/audio-mixer.h>
7
8#include <mgba/core/blip_buf.h>
9#include <mgba/internal/gba/gba.h>
10#include <mgba/internal/gba/video.h>
11
12#define OVERSAMPLE 2
13
14static void _mp2kInit(void* cpu, struct mCPUComponent* component);
15static void _mp2kDeinit(struct mCPUComponent* component);
16
17static bool _mp2kEngage(struct GBAAudioMixer* mixer, uint32_t address);
18static void _mp2kVblank(struct GBAAudioMixer* mixer);
19static void _mp2kStep(struct GBAAudioMixer* mixer);
20
21void GBAAudioMixerCreate(struct GBAAudioMixer* mixer) {
22 mixer->d.init = _mp2kInit;
23 mixer->d.deinit = _mp2kDeinit;
24 mixer->engage = _mp2kEngage;
25 mixer->vblank = _mp2kVblank;
26 mixer->step = _mp2kStep;
27}
28
29void _mp2kInit(void* cpu, struct mCPUComponent* component) {
30 struct ARMCore* arm = cpu;
31 struct GBA* gba = (struct GBA*) arm->master;
32 struct GBAAudioMixer* mixer = (struct GBAAudioMixer*) component;
33 gba->audio.mixer = mixer;
34 mixer->p = &gba->audio;
35 mixer->contextAddress = 0;
36 mixer->tempo = 120.0 / 75.0;
37 mixer->frame = 0;
38 mixer->last.left = 0;
39 mixer->last.right = 0;
40 memset(&mixer->context, 0, sizeof(mixer->context));
41 memset(&mixer->activeTracks, 0, sizeof(mixer->activeTracks));
42
43 size_t i;
44 for (i = 0; i < MP2K_MAX_SOUND_CHANNELS; ++i) {
45 mixer->activeTracks[i].channel = &mixer->context.chans[i];
46 CircleBufferInit(&mixer->activeTracks[i].buffer, 0x10000);
47 }
48}
49
50void _mp2kDeinit(struct mCPUComponent* component) {
51 struct GBAAudioMixer* mixer = (struct GBAAudioMixer*) component;
52 size_t i;
53 for (i = 0; i < MP2K_MAX_SOUND_CHANNELS; ++i) {
54 CircleBufferDeinit(&mixer->activeTracks[i].buffer);
55 }
56}
57
58static void _loadInstrument(struct ARMCore* cpu, struct GBAMP2kInstrument* instrument, uint32_t base) {
59 struct ARMMemory* memory = &cpu->memory;
60 instrument->type = memory->load8(cpu, base + offsetof(struct GBAMP2kInstrument, type), 0);
61 instrument->key = memory->load8(cpu, base + offsetof(struct GBAMP2kInstrument, key), 0);
62 instrument->length = memory->load8(cpu, base + offsetof(struct GBAMP2kInstrument, length), 0);
63 instrument->ps.pan = memory->load8(cpu, base + offsetof(struct GBAMP2kInstrument, ps.pan), 0);
64 if (instrument->type == 0x40 || instrument->type == 0x80) {
65 instrument->data.subTable = memory->load32(cpu, base + offsetof(struct GBAMP2kInstrument, data.subTable), 0);
66 instrument->extInfo.map = memory->load32(cpu, base + offsetof(struct GBAMP2kInstrument, extInfo.map), 0);
67 } else {
68 instrument->data.waveData = memory->load32(cpu, base + offsetof(struct GBAMP2kInstrument, data.waveData), 0);
69 instrument->extInfo.adsr.attack = memory->load8(cpu, base + offsetof(struct GBAMP2kInstrument, extInfo.adsr.attack), 0);
70 instrument->extInfo.adsr.decay = memory->load8(cpu, base + offsetof(struct GBAMP2kInstrument, extInfo.adsr.decay), 0);
71 instrument->extInfo.adsr.sustain = memory->load8(cpu, base + offsetof(struct GBAMP2kInstrument, extInfo.adsr.sustain), 0);
72 instrument->extInfo.adsr.release = memory->load8(cpu, base + offsetof(struct GBAMP2kInstrument, extInfo.adsr.release), 0);
73 }
74}
75
76static void _lookupInstrument(struct ARMCore* cpu, struct GBAMP2kInstrument* instrument, uint8_t key) {
77 struct ARMMemory* memory = &cpu->memory;
78 if (instrument->type == 0x40) {
79 uint32_t subInstrumentBase = instrument->data.subTable;
80 uint32_t keyTable = instrument->extInfo.map;
81 uint8_t id = memory->load8(cpu, keyTable + key, 0);
82 subInstrumentBase += 12 * id;
83 _loadInstrument(cpu, instrument, subInstrumentBase);
84 }
85 if (instrument->type == 0x80) {
86 uint32_t subInstrumentBase = instrument->data.subTable;
87 subInstrumentBase += 12 * key;
88 _loadInstrument(cpu, instrument, subInstrumentBase);
89 }
90}
91
92static void _stepSample(struct GBAAudioMixer* mixer, struct GBAMP2kTrack* track) {
93 struct ARMCore* cpu = mixer->p->p->cpu;
94 struct ARMMemory* memory = &cpu->memory;
95 uint32_t headerAddress;
96 struct GBAMP2kInstrument instrument = track->track.instrument;
97
98 uint8_t note = track->track.key;
99 _lookupInstrument(cpu, &instrument, note);
100 double freq;
101
102 switch (instrument.type) {
103 case 0x00:
104 case 0x08:
105 case 0x40:
106 case 0x80:
107 freq = GBA_ARM7TDMI_FREQUENCY / (double) track->channel->freq;
108 break;
109 default:
110 // We don't care about PSG channels
111 return;
112 }
113 headerAddress = instrument.data.waveData;
114 if (headerAddress < 0x20) {
115 mLOG(GBA_AUDIO, ERROR, "Audio track has invalid instrument");
116 return;
117 }
118 uint32_t loopOffset = memory->load32(cpu, headerAddress + 0x8, 0);
119 uint32_t endOffset = memory->load32(cpu, headerAddress + 0xC, 0);
120 uint32_t sampleBase = headerAddress + 0x10;
121 uint32_t sampleI = track->samplePlaying;
122 double sampleOffset = track->currentOffset;
123 double updates = VIDEO_TOTAL_LENGTH / (mixer->tempo * mixer->p->sampleInterval / OVERSAMPLE);
124 int nSample;
125 for (nSample = 0; nSample < updates; ++nSample) {
126 int8_t sample = memory->load8(cpu, sampleBase + sampleI, 0);
127
128 struct GBAStereoSample stereo = {
129 (sample * track->channel->leftVolume * track->channel->envelopeV) >> 9,
130 (sample * track->channel->rightVolume * track->channel->envelopeV) >> 9
131 };
132
133 CircleBufferWrite16(&track->buffer, stereo.left);
134 CircleBufferWrite16(&track->buffer, stereo.right);
135
136 sampleOffset += mixer->p->sampleInterval / OVERSAMPLE;
137 while (sampleOffset > freq) {
138 sampleOffset -= freq;
139 ++sampleI;
140 if (sampleI >= endOffset) {
141 sampleI = loopOffset;
142 }
143 }
144 }
145
146 track->samplePlaying = sampleI;
147 track->currentOffset = sampleOffset;
148}
149
150static void _mp2kReload(struct GBAAudioMixer* mixer) {
151 struct ARMCore* cpu = mixer->p->p->cpu;
152 struct ARMMemory* memory = &cpu->memory;
153 mixer->context.magic = memory->load32(cpu, mixer->contextAddress + offsetof(struct GBAMP2kContext, magic), 0);
154 int i;
155 for (i = 0; i < MP2K_MAX_SOUND_CHANNELS; ++i) {
156 struct GBAMP2kSoundChannel* ch = &mixer->context.chans[i];
157 struct GBAMP2kTrack* track = &mixer->activeTracks[i];
158 track->waiting = false;
159 uint32_t base = mixer->contextAddress + offsetof(struct GBAMP2kContext, chans[i]);
160
161 ch->status = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, status), 0);
162 ch->type = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, type), 0);
163 ch->rightVolume = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, rightVolume), 0);
164 ch->leftVolume = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, leftVolume), 0);
165 ch->adsr.attack = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, adsr.attack), 0);
166 ch->adsr.decay = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, adsr.decay), 0);
167 ch->adsr.sustain = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, adsr.sustain), 0);
168 ch->adsr.release = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, adsr.release), 0);
169 ch->ky = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, ky), 0);
170 ch->envelopeV = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, envelopeV), 0);
171 ch->envelopeRight = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, envelopeRight), 0);
172 ch->envelopeLeft = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, envelopeLeft), 0);
173 ch->echoVolume = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, echoVolume), 0);
174 ch->echoLength = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, echoLength), 0);
175 ch->d1 = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, d1), 0);
176 ch->d2 = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, d2), 0);
177 ch->gt = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, gt), 0);
178 ch->midiKey = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, midiKey), 0);
179 ch->ve = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, ve), 0);
180 ch->pr = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, pr), 0);
181 ch->rp = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, rp), 0);
182 ch->d3[0] = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, d3[0]), 0);
183 ch->d3[1] = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, d3[1]), 0);
184 ch->d3[2] = memory->load8(cpu, base + offsetof(struct GBAMP2kSoundChannel, d3[2]), 0);
185 ch->ct = memory->load32(cpu, base + offsetof(struct GBAMP2kSoundChannel, ct), 0);
186 ch->fw = memory->load32(cpu, base + offsetof(struct GBAMP2kSoundChannel, fw), 0);
187 ch->freq = memory->load32(cpu, base + offsetof(struct GBAMP2kSoundChannel, freq), 0);
188 ch->waveData = memory->load32(cpu, base + offsetof(struct GBAMP2kSoundChannel, waveData), 0);
189 ch->cp = memory->load32(cpu, base + offsetof(struct GBAMP2kSoundChannel, cp), 0);
190 ch->track = memory->load32(cpu, base + offsetof(struct GBAMP2kSoundChannel, track), 0);
191 ch->pp = memory->load32(cpu, base + offsetof(struct GBAMP2kSoundChannel, pp), 0);
192 ch->np = memory->load32(cpu, base + offsetof(struct GBAMP2kSoundChannel, np), 0);
193 ch->d4 = memory->load32(cpu, base + offsetof(struct GBAMP2kSoundChannel, d4), 0);
194 ch->xpi = memory->load16(cpu, base + offsetof(struct GBAMP2kSoundChannel, xpi), 0);
195 ch->xpc = memory->load16(cpu, base + offsetof(struct GBAMP2kSoundChannel, xpc), 0);
196
197 base = ch->track;
198 if (base) {
199 track->track.flags = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, flags), 0);
200 track->track.wait = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, wait), 0);
201 track->track.patternLevel = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, patternLevel), 0);
202 track->track.repN = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, repN), 0);
203 track->track.gateTime = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, gateTime), 0);
204 track->track.key = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, key), 0);
205 track->track.velocity = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, velocity), 0);
206 track->track.runningStatus = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, runningStatus), 0);
207 track->track.keyM = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, keyM), 0);
208 track->track.pitM = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, pitM), 0);
209 track->track.keyShift = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, keyShift), 0);
210 track->track.keyShiftX = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, keyShiftX), 0);
211 track->track.tune = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, tune), 0);
212 track->track.pitX = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, pitX), 0);
213 track->track.bend = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, bend), 0);
214 track->track.bendRange = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, bendRange), 0);
215 track->track.volMR = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, volMR), 0);
216 track->track.volML = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, volML), 0);
217 track->track.vol = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, vol), 0);
218 track->track.volX = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, volX), 0);
219 track->track.pan = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, pan), 0);
220 track->track.panX = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, panX), 0);
221 track->track.modM = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, modM), 0);
222 track->track.mod = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, mod), 0);
223 track->track.modT = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, modT), 0);
224 track->track.lfoSpeed = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, lfoSpeed), 0);
225 track->track.lfoSpeedC = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, lfoSpeedC), 0);
226 track->track.lfoDelay = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, lfoDelay), 0);
227 track->track.lfoDelayC = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, lfoDelayC), 0);
228 track->track.priority = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, priority), 0);
229 track->track.echoVolume = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, echoVolume), 0);
230 track->track.echoLength = memory->load8(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, echoLength), 0);
231 track->track.chan = memory->load32(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, chan), 0);
232 _loadInstrument(cpu, &track->track.instrument, base + offsetof(struct GBAMP2kMusicPlayerTrack, instrument));
233 track->track.cmdPtr = memory->load32(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, cmdPtr), 0);
234 track->track.patternStack[0] = memory->load32(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, patternStack[0]), 0);
235 track->track.patternStack[1] = memory->load32(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, patternStack[1]), 0);
236 track->track.patternStack[2] = memory->load32(cpu, base + offsetof(struct GBAMP2kMusicPlayerTrack, patternStack[2]), 0);
237 } else {
238 memset(&track->track, 0, sizeof(track->track));
239 }
240 }
241}
242
243bool _mp2kEngage(struct GBAAudioMixer* mixer, uint32_t address) {
244 if (address < BASE_WORKING_RAM) {
245 return false;
246 }
247 if (address != mixer->contextAddress) {
248 mixer->contextAddress = address;
249 mixer->p->externalMixing = true;
250 _mp2kReload(mixer);
251 }
252 return true;
253}
254
255void _mp2kStep(struct GBAAudioMixer* mixer) {
256 if (!mixer->p->externalMixing) {
257 return;
258 }
259 mixer->frame += mixer->p->sampleInterval;
260
261 while (mixer->frame >= VIDEO_TOTAL_LENGTH / mixer->tempo) {
262 int i;
263 for (i = 0; i < MP2K_MAX_SOUND_CHANNELS; ++i) {
264 struct GBAMP2kTrack* track = &mixer->activeTracks[i];
265 if (track->channel->status > 0) {
266 _stepSample(mixer, track);
267 } else {
268 track->currentOffset = 0;
269 track->samplePlaying = 0;
270 CircleBufferClear(&track->buffer);
271 }
272 }
273 mixer->frame -= VIDEO_TOTAL_LENGTH / mixer->tempo;
274 }
275
276 uint32_t interval = mixer->p->sampleInterval / OVERSAMPLE;
277 int i;
278 for (i = 0; i < OVERSAMPLE; ++i) {
279 struct GBAStereoSample sample = {0};
280 size_t track;
281 for (track = 0; track < MP2K_MAX_SOUND_CHANNELS; ++track) {
282 if (!mixer->activeTracks[track].channel->status) {
283 continue;
284 }
285 int16_t value;
286 CircleBufferRead16(&mixer->activeTracks[track].buffer, &value);
287 sample.left += value;
288 CircleBufferRead16(&mixer->activeTracks[track].buffer, &value);
289 sample.right += value;
290 }
291 blip_add_delta(mixer->p->psg.left, mixer->p->clock + i * interval, sample.left - mixer->last.left);
292 blip_add_delta(mixer->p->psg.right, mixer->p->clock + i * interval, sample.left - mixer->last.left);
293 mixer->last = sample;
294 }
295}
296
297void _mp2kVblank(struct GBAAudioMixer* mixer) {
298 if (!mixer->contextAddress) {
299 return;
300 }
301 mLOG(GBA_AUDIO, DEBUG, "Frame");
302 mixer->p->externalMixing = true;
303 _mp2kReload(mixer);
304}