scummvm/backends/platform/wii/osystem_sfx.cpp
2021-12-26 18:48:43 +01:00

134 lines
3.5 KiB
C++

/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#define FORBIDDEN_SYMBOL_EXCEPTION_printf
#include <malloc.h>
#include "osystem.h"
#define SFX_THREAD_STACKSIZE (1024 * 128)
#define SFX_THREAD_PRIO 80
#define SFX_THREAD_FRAG_SIZE (1024 * 8)
#define SFX_BUFFERS 3
static lwpq_t sfx_queue;
static lwp_t sfx_thread;
static u8 *sfx_stack;
static bool sfx_thread_running = false;
static bool sfx_thread_quit = false;
static u32 sb_hw;
static u8 *sound_buffer[SFX_BUFFERS];
static void audio_switch_buffers() {
sb_hw = (sb_hw + 1) % SFX_BUFFERS;
AUDIO_InitDMA((u32) sound_buffer[sb_hw], SFX_THREAD_FRAG_SIZE);
LWP_ThreadSignal(sfx_queue);
}
static void * sfx_thread_func(void *arg) {
Audio::MixerImpl *mixer = (Audio::MixerImpl *) arg;
u8 sb_sw;
while (true) {
LWP_ThreadSleep(sfx_queue);
if (sfx_thread_quit)
break;
// the hardware uses two buffers: a front and a back buffer
// we use 3 buffers here: two are beeing pushed to the DSP,
// and the free one is where our mixer writes to
// thus the latency of our stream is:
// 8192 [frag size] / 48000 / 2 [16bit] / 2 [stereo] * 2 [hw buffers]
// -> 85.3ms
sb_sw = (sb_hw + 1) % SFX_BUFFERS;
mixer->mixCallback(sound_buffer[sb_sw], SFX_THREAD_FRAG_SIZE);
DCFlushRange(sound_buffer[sb_sw], SFX_THREAD_FRAG_SIZE);
}
return NULL;
}
void OSystem_Wii::initSfx() {
_mixer = new Audio::MixerImpl(48000);
sfx_thread_running = false;
sfx_thread_quit = false;
sfx_stack = (u8 *) memalign(32, SFX_THREAD_STACKSIZE);
if (sfx_stack) {
memset(sfx_stack, 0, SFX_THREAD_STACKSIZE);
LWP_InitQueue(&sfx_queue);
s32 res = LWP_CreateThread(&sfx_thread, sfx_thread_func, _mixer, sfx_stack,
SFX_THREAD_STACKSIZE, SFX_THREAD_PRIO);
if (res) {
printf("ERROR creating sfx thread: %d\n", res);
LWP_CloseQueue(sfx_queue);
return;
}
sfx_thread_running = true;
}
for (u32 i = 0; i < SFX_BUFFERS; ++i) {
sound_buffer[i] = (u8 *) memalign(32, SFX_THREAD_FRAG_SIZE);
memset(sound_buffer[i], 0, SFX_THREAD_FRAG_SIZE);
DCFlushRange(sound_buffer[i], SFX_THREAD_FRAG_SIZE);
}
_mixer->setReady(true);
sb_hw = 0;
AUDIO_SetDSPSampleRate(AI_SAMPLERATE_48KHZ);
AUDIO_RegisterDMACallback(audio_switch_buffers);
AUDIO_InitDMA((u32) sound_buffer[sb_hw], SFX_THREAD_FRAG_SIZE);
AUDIO_StartDMA();
}
void OSystem_Wii::deinitSfx() {
if (_mixer)
_mixer->setReady(false);
AUDIO_StopDMA();
AUDIO_RegisterDMACallback(NULL);
if (sfx_thread_running) {
sfx_thread_quit = true;
LWP_ThreadBroadcast(sfx_queue);
LWP_JoinThread(sfx_thread, NULL);
LWP_CloseQueue(sfx_queue);
free(sfx_stack);
sfx_thread_running = false;
for (u32 i = 0; i < SFX_BUFFERS; ++i)
free(sound_buffer[i]);
}
}