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Diffstat (limited to 'backends/gp32/gp32std_sound.cpp')
| -rw-r--r-- | backends/gp32/gp32std_sound.cpp | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/backends/gp32/gp32std_sound.cpp b/backends/gp32/gp32std_sound.cpp new file mode 100644 index 0000000000..2bef7aac3a --- /dev/null +++ b/backends/gp32/gp32std_sound.cpp @@ -0,0 +1,107 @@ +/* ScummVM - Scumm Interpreter + * Copyright (C) 2001-2005 The ScummVM project + * Copyright (C) 2002 Ph0x - GP32 Backend + * Copyright (C) 2003/2004 DJWillis - GP32 Backend + * Copyright (C) 2005 Won Star - GP32 Backend + * + * 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 2 + * 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, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * + * $Header$ + * + */ + +#include "stdafx.h" +#include "common/scummsys.h" + +#include "gp32std.h" +#include "gp32std_sound.h" + +#define GP32_TIMER_AUDIO_IDX 0 + +// Global variables +static volatile unsigned int frame = 0; +static volatile unsigned int *soundPos = 0; +static volatile int idx_buf; +static volatile unsigned int shiftVal = 0; +static void *buffer; +static GPSOUNDBUF soundBuf; + +// This routine gets called by the timer interrupt and +// polls the current playing position within the buffer. + +static void soundTimer() { + unsigned int t = (((unsigned int)(*soundPos) - (unsigned int)buffer) >> shiftVal) >= soundBuf.samples ? 1 : 0; + if (t != frame) { + unsigned int offs = ((frame == 1) ? (soundBuf.samples << shiftVal) : 0); + soundBuf.callback(soundBuf.userdata, (uint8 *)((unsigned int)buffer + offs), soundBuf.samples << shiftVal); + frame = t; + } +} + +int gp_soundBufStart(GPSOUNDBUF *sb) { + int bufferSize = 0; + frame = 0; + + // Copy the structure + memcpy(&soundBuf, sb, sizeof(GPSOUNDBUF)); + + // Calculate size of a single sample in bytes + // and a corresponding shift value + shiftVal = 0; + switch (soundBuf.freq) { + case PCM_S11: + break; + case PCM_S22: + break; + case PCM_S44: + shiftVal++; + break; + case PCM_M11: + break; + case PCM_M22: + break; + case PCM_M44: + shiftVal++; + break; + } + if (soundBuf.format == PCM_16BIT) + shiftVal++; + soundBuf.samplesize = 1 << shiftVal; + + // Allocate memory for the playing buffer + bufferSize = soundBuf.samplesize * soundBuf.samples * 2; + buffer = malloc(bufferSize); + memset(buffer, 0, bufferSize); + + // Set timer interrupt + if (GpTimerOptSet(GP32_TIMER_AUDIO_IDX, soundBuf.pollfreq, 0, soundTimer) == GPOS_ERR_ALREADY_USED) { + NP(" Timer is already used... kill timer"); + GpTimerKill(GP32_TIMER_AUDIO_IDX); + } + GpTimerSet(GP32_TIMER_AUDIO_IDX); + // Start playing + GpPcmInit(soundBuf.freq, soundBuf.format); + GpPcmPlay((unsigned short *)buffer, bufferSize, 1); + GpPcmLock((unsigned short *)buffer, (int *)&idx_buf, (unsigned int *)&soundPos); + + return 0; +} + +void gp_soundBufStop() { + GpPcmStop(); + GpPcmRemove((unsigned short *)buffer); + GpTimerKill(GP32_TIMER_AUDIO_IDX); + free(buffer); +} |