license info for PicoDrive directory

[cyclone68000.git] / PicoDrive / Wave.cpp

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// This file is part of the PicoDrive Megadrive Emulator\r
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// This code is licensed under the GNU General Public License version 2.0 and the MAME License.\r
// You can choose the license that has the most advantages for you.\r
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// SVN repository can be found at http://code.google.com/p/cyclone68000/\r
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#include "stdafx.h"\r
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int WaveRate=0;\r
int WaveLen=0; // Length of each buffer in samples\r
short *WaveDest=NULL; // Destination to render sound\r
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static HWAVEOUT WaveOut=NULL;\r
static short *WaveBuf=NULL; // Wave double-buffer\r
static WAVEHDR WaveHeader[2]; // WAVEHDR for each buffer\r
static int WavePlay=0; // Next buffer side to play\r
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int WaveInit()\r
{\r
  WAVEFORMATEX wfx;\r
  WAVEHDR *pwh=NULL;\r
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  if (WaveOut) return 0; // Already initted\r
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  memset(&wfx,0,sizeof(wfx));\r
  memset(&WaveHeader,0,sizeof(WaveHeader));\r
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  wfx.wFormatTag=WAVE_FORMAT_PCM;\r
  wfx.nChannels=2; // stereo\r
  wfx.nSamplesPerSec=WaveRate; // sample rate\r
  wfx.wBitsPerSample=16;\r
  // Calculate bytes per sample and per second\r
  wfx.nBlockAlign=(unsigned short)( (wfx.wBitsPerSample>>3)*wfx.nChannels );\r
  wfx.nAvgBytesPerSec=wfx.nSamplesPerSec*wfx.nBlockAlign;\r
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  waveOutOpen(&WaveOut,WAVE_MAPPER,&wfx,0,NULL,CALLBACK_NULL);\r
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  // Allocate both buffers\r
  WaveBuf=(short *)malloc(WaveLen<<3);\r
  if (WaveBuf==NULL) return 1;\r
  memset(WaveBuf,0,WaveLen<<3);\r
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  // Make WAVEHDRs for both buffers\r
  pwh=WaveHeader+0;\r
  pwh->lpData=(char *)WaveBuf;\r
  pwh->dwBufferLength=WaveLen<<2;\r
  pwh->dwLoops=1;\r
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  pwh=WaveHeader+1;\r
  *pwh=WaveHeader[0]; pwh->lpData+=WaveLen<<2;\r
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  // Prepare the buffers\r
  waveOutPrepareHeader(WaveOut,WaveHeader,  sizeof(WAVEHDR));\r
  waveOutPrepareHeader(WaveOut,WaveHeader+1,sizeof(WAVEHDR));\r
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  // Queue both buffers:\r
  WavePlay=0;\r
  WaveHeader[0].dwFlags|=WHDR_DONE;\r
  WaveHeader[1].dwFlags|=WHDR_DONE;\r
  WaveUpdate();\r
  return 0;\r
}\r
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int WaveExit()\r
{\r
  WAVEHDR *pwh=NULL;\r
  int i=0;\r
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  if (WaveOut) waveOutReset(WaveOut);\r
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  for (i=0;i<2;i++)\r
  {\r
    pwh=WaveHeader+i;\r
    if (pwh->lpData) waveOutUnprepareHeader(WaveOut,pwh,sizeof(*pwh));\r
  }\r
  memset(WaveHeader,0,sizeof(WaveHeader));\r
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  free(WaveBuf); WaveBuf=NULL; WaveLen=0;\r
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  if (WaveOut) waveOutClose(WaveOut);  WaveOut=NULL;\r
  return 0;\r
}\r
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int WaveUpdate()\r
{\r
  WAVEHDR *pwh=NULL; int i=0;\r
  int Last=-1;\r
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  for (i=0;i<2;i++)\r
  {\r
    pwh=WaveHeader+WavePlay;\r
    if (pwh->lpData==NULL) return 1; // Not initted\r
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    if (pwh->dwFlags&WHDR_DONE)\r
    {\r
      // This buffer has finished - start it playing again\r
      WaveDest=(short *)pwh->lpData;\r
      SndRender();\r
      WaveDest=NULL;\r
      \r
      waveOutWrite(WaveOut,pwh,sizeof(*pwh));\r
      Last=WavePlay; // Remember the last buffer we played\r
    }\r
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    WavePlay++; WavePlay&=1;\r
  }\r
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  if (Last>=0) WavePlay=Last^1; // Next buffer to play is the other one\r
  return 0;\r
}\r