virtch2.c

wince下著名的视频播放器源码

{
	float x1,x2,tmpx;
	int i;

	for(count/=SAMPLING_FACTOR;count;count--) {
		tmpx=0.0f;

		for(i=SAMPLING_FACTOR/2;i;i--) {
			EXTRACT_SAMPLE_FP(x1,1.0f); EXTRACT_SAMPLE_FP(x2,1.0f);

			CHECK_SAMPLE_FP(x1,1.0f); CHECK_SAMPLE_FP(x2,1.0f);

			tmpx+=x1+x2;
		}
		*dste++ =tmpx*(1.0f/SAMPLING_FACTOR);
	}
}

static void Mix32ToFP_Stereo(float* dste,SLONG* srce,NATIVE count)
{
	float x1,x2,x3,x4,tmpx,tmpy;
	int i;

	for(count/=SAMPLING_FACTOR;count;count--) {
		tmpx=tmpy=0.0f;

		for(i=SAMPLING_FACTOR/2;i;i--) {
			EXTRACT_SAMPLE_FP(x1,1.0f); EXTRACT_SAMPLE_FP(x2,1.0f);
			EXTRACT_SAMPLE_FP(x3,1.0f); EXTRACT_SAMPLE_FP(x4,1.0f);

			CHECK_SAMPLE_FP(x1,1.0f); CHECK_SAMPLE_FP(x2,1.0f);
			CHECK_SAMPLE_FP(x3,1.0f); CHECK_SAMPLE_FP(x4,1.0f);

			tmpx+=x1+x3;
			tmpy+=x2+x4;
		}
		*dste++ =tmpx*(1.0f/SAMPLING_FACTOR);
		*dste++ =tmpy*(1.0f/SAMPLING_FACTOR);
	}
}

/* Mixing macros */
#define EXTRACT_SAMPLE(var,attenuation) var=*srce++/(MAXVOL_FACTOR*attenuation)
#define CHECK_SAMPLE(var,bound) var=(var>=bound)?bound-1:(var<-bound)?-bound:var

static void Mix32To16_Normal(SWORD* dste,SLONG* srce,NATIVE count)
{
	NATIVE x1,x2,tmpx;
	int i;

	for(count/=SAMPLING_FACTOR;count;count--) {
		tmpx=0;

		for(i=SAMPLING_FACTOR/2;i;i--) {
			EXTRACT_SAMPLE(x1,1); EXTRACT_SAMPLE(x2,1);

			CHECK_SAMPLE(x1,32768); CHECK_SAMPLE(x2,32768);

			tmpx+=x1+x2;
		}
		*dste++ =tmpx/SAMPLING_FACTOR;
	}
}

static void Mix32To16_Stereo(SWORD* dste,SLONG* srce,NATIVE count)
{
	NATIVE x1,x2,x3,x4,tmpx,tmpy;
	int i;

	for(count/=SAMPLING_FACTOR;count;count--) {
		tmpx=tmpy=0;

		for(i=SAMPLING_FACTOR/2;i;i--) {
			EXTRACT_SAMPLE(x1,1); EXTRACT_SAMPLE(x2,1);
			EXTRACT_SAMPLE(x3,1); EXTRACT_SAMPLE(x4,1);

			CHECK_SAMPLE(x1,32768); CHECK_SAMPLE(x2,32768);
			CHECK_SAMPLE(x3,32768); CHECK_SAMPLE(x4,32768);

			tmpx+=x1+x3;
			tmpy+=x2+x4;
		}
		*dste++ =tmpx/SAMPLING_FACTOR;
		*dste++ =tmpy/SAMPLING_FACTOR;
	}
}

static void Mix32To8_Normal(SBYTE* dste,SLONG* srce,NATIVE count)
{
	NATIVE x1,x2,tmpx;
	int i;

	for(count/=SAMPLING_FACTOR;count;count--) {
		tmpx = 0;

		for(i=SAMPLING_FACTOR/2;i;i--) {
			EXTRACT_SAMPLE(x1,256); EXTRACT_SAMPLE(x2,256);

			CHECK_SAMPLE(x1,128); CHECK_SAMPLE(x2,128);

			tmpx+=x1+x2;
		}
		*dste++ =(tmpx/SAMPLING_FACTOR)+128;
	}
}

static void Mix32To8_Stereo(SBYTE* dste,SLONG* srce,NATIVE count)
{
	NATIVE x1,x2,x3,x4,tmpx,tmpy;
	int i;

	for(count/=SAMPLING_FACTOR;count;count--) {
		tmpx=tmpy=0;

		for(i=SAMPLING_FACTOR/2;i;i--) {
			EXTRACT_SAMPLE(x1,256); EXTRACT_SAMPLE(x2,256);
			EXTRACT_SAMPLE(x3,256); EXTRACT_SAMPLE(x4,256);

			CHECK_SAMPLE(x1,128); CHECK_SAMPLE(x2,128);
			CHECK_SAMPLE(x3,128); CHECK_SAMPLE(x4,128);

			tmpx+=x1+x3;
			tmpy+=x2+x4;
		}
		*dste++ =(tmpx/SAMPLING_FACTOR)+128;        
		*dste++ =(tmpy/SAMPLING_FACTOR)+128;        
	}
}

static void AddChannel(SLONG* ptr,NATIVE todo)
{
	SLONGLONG end,done;
	SWORD *s;

	if(!(s=Samples[vnf->handle])) {
		vnf->current = vnf->active  = 0;
		vnf->lastvalL = vnf->lastvalR = 0;
		return;
	}

	/* update the 'current' index so the sample loops, or stops playing if it
	   reached the end of the sample */
	while(todo>0) {
		SLONGLONG endpos;

		if(vnf->flags & SF_REVERSE) {
			/* The sample is playing in reverse */
			if((vnf->flags&SF_LOOP)&&(vnf->current<idxlpos)) {
				/* the sample is looping and has reached the loopstart index */
				if(vnf->flags & SF_BIDI) {
					/* sample is doing bidirectional loops, so 'bounce' the
					   current index against the idxlpos */
					vnf->current = idxlpos+(idxlpos-vnf->current);
					vnf->flags &= ~SF_REVERSE;
					vnf->increment = -vnf->increment;
				} else
					/* normal backwards looping, so set the current position to
					   loopend index */
					vnf->current=idxlend-(idxlpos-vnf->current);
			} else {
				/* the sample is not looping, so check if it reached index 0 */
				if(vnf->current < 0) {
					/* playing index reached 0, so stop playing this sample */
					vnf->current = vnf->active  = 0;
					break;
				}
			}
		} else {
			/* The sample is playing forward */
			if((vnf->flags & SF_LOOP) &&
			   (vnf->current >= idxlend)) {
				/* the sample is looping, check the loopend index */
				if(vnf->flags & SF_BIDI) {
					/* sample is doing bidirectional loops, so 'bounce' the
					   current index against the idxlend */
					vnf->flags |= SF_REVERSE;
					vnf->increment = -vnf->increment;
					vnf->current = idxlend-(vnf->current-idxlend);
				} else
					/* normal backwards looping, so set the current position
					   to loopend index */
					vnf->current=idxlpos+(vnf->current-idxlend);
			} else {
				/* sample is not looping, so check if it reached the last
				   position */
				if(vnf->current >= idxsize) {
					/* yes, so stop playing this sample */
					vnf->current = vnf->active  = 0;
					break;
				}
			}
		}

		end=(vnf->flags&SF_REVERSE)?(vnf->flags&SF_LOOP)?idxlpos:0:
		     (vnf->flags&SF_LOOP)?idxlend:idxsize;

		/* if the sample is not blocked... */
		if((end==vnf->current)||(!vnf->increment))
			done=0;
		else {
			done=MIN((end-vnf->current)/vnf->increment+1,todo);
			if(done<0) done=0;
		}

		if(!done) {
			vnf->active = 0;
			break;
		}

		endpos=vnf->current+done*vnf->increment;

		if(vnf->vol || vnf->rampvol) {
#ifndef NATIVE_64BIT_INT
			/* use the 32 bit mixers as often as we can (they're much faster) */
			if((vnf->current<0x7fffffff)&&(endpos<0x7fffffff)) {
				if(vc_mode & DMODE_STEREO) {
					if((vnf->pan==PAN_SURROUND)&&(vc_mode&DMODE_SURROUND))
						vnf->current=Mix32StereoSurround
						               (s,ptr,vnf->current,vnf->increment,done);
					else
						vnf->current=Mix32StereoNormal
						               (s,ptr,vnf->current,vnf->increment,done);
				} else
					vnf->current=Mix32MonoNormal
					                   (s,ptr,vnf->current,vnf->increment,done);
			} else
#endif
			       {
				if(vc_mode & DMODE_STEREO) {
					if((vnf->pan==PAN_SURROUND)&&(vc_mode&DMODE_SURROUND))
						vnf->current=MixStereoSurround
						               (s,ptr,vnf->current,vnf->increment,done);
					else
						vnf->current=MixStereoNormal
						               (s,ptr,vnf->current,vnf->increment,done);
				} else
					vnf->current=MixMonoNormal
					                   (s,ptr,vnf->current,vnf->increment,done);
			}
		} else  {
			vnf->lastvalL = vnf->lastvalR = 0;
			/* update sample position */
			vnf->current=endpos;
		}

		todo -= done;
		ptr +=(vc_mode & DMODE_STEREO)?(done<<1):done;
	}
}

#define _IN_VIRTCH_

#define VC1_SilenceBytes      VC2_SilenceBytes
#define VC1_WriteSamples      VC2_WriteSamples
#define VC1_WriteBytes        VC2_WriteBytes
#define VC1_Exit              VC2_Exit
#define VC1_VoiceSetVolume    VC2_VoiceSetVolume
#define VC1_VoiceGetVolume    VC2_VoiceGetVolume
#define VC1_VoiceSetPanning   VC2_VoiceSetPanning
#define VC1_VoiceGetPanning   VC2_VoiceGetPanning
#define VC1_VoiceSetFrequency VC2_VoiceSetFrequency
#define VC1_VoiceGetFrequency VC2_VoiceGetFrequency
#define VC1_VoicePlay         VC2_VoicePlay
#define VC1_VoiceStop         VC2_VoiceStop
#define VC1_VoiceStopped      VC2_VoiceStopped
#define VC1_VoiceGetPosition  VC2_VoiceGetPosition
#define VC1_SampleUnload      VC2_SampleUnload
#define VC1_SampleLoad        VC2_SampleLoad
#define VC1_SampleSpace       VC2_SampleSpace
#define VC1_SampleLength      VC2_SampleLength
#define VC1_VoiceRealVolume   VC2_VoiceRealVolume

#include "virtch_common.c"
#undef _IN_VIRTCH_

void VC2_WriteSamples(SBYTE* buf,ULONG todo)
{
	int left,portion=0;
	SBYTE *buffer;
	int t,pan,vol;

	todo*=SAMPLING_FACTOR;

	while(todo) {
		if(!tickleft) {
			if(vc_mode & DMODE_SOFT_MUSIC) md_player();
			tickleft=(md_mixfreq*125L*SAMPLING_FACTOR)/(md_bpm*50L);
			tickleft&=~(SAMPLING_FACTOR-1);
		}
		left = MIN(tickleft, todo);
		buffer    = buf;
		tickleft -= left;
		todo     -= left;
		buf += samples2bytes(left)/SAMPLING_FACTOR;

		while(left) {
			portion = MIN(left, samplesthatfit);
			memset(vc_tickbuf,0,portion<<((vc_mode&DMODE_STEREO)?3:2));
			for(t=0;t<vc_softchn;t++) {
				vnf = &vinf[t];

				if(vnf->kick) {
					vnf->current=((SLONGLONG)(vnf->start))<<FRACBITS;
					vnf->kick    = 0;
					vnf->active  = 1;
					vnf->click   = CLICK_BUFFER;
					vnf->rampvol = 0;
				}

				if(!vnf->frq) vnf->active = 0;

				if(vnf->active) {
					vnf->increment=((SLONGLONG)(vnf->frq)<<(FRACBITS-SAMPLING_SHIFT))
					               /md_mixfreq;
					if(vnf->flags&SF_REVERSE) vnf->increment=-vnf->increment;
					vol = vnf->vol;  pan = vnf->pan;

					vnf->oldlvol=vnf->lvolsel;vnf->oldrvol=vnf->rvolsel;
					if(vc_mode & DMODE_STEREO) {
						if(pan!=PAN_SURROUND) {
							vnf->lvolsel=(vol*(PAN_RIGHT-pan))>>8;
							vnf->rvolsel=(vol*pan)>>8;
						} else {
							vnf->lvolsel=vnf->rvolsel=(vol * 256L) / 480;
						}
					} else
						vnf->lvolsel=vol;

					idxsize=(vnf->size)?((SLONGLONG)(vnf->size)<<FRACBITS)-1:0;
					idxlend=(vnf->repend)?((SLONGLONG)(vnf->repend)<<FRACBITS)-1:0;
					idxlpos=(SLONGLONG)(vnf->reppos)<<FRACBITS;
					AddChannel(vc_tickbuf,portion);
				}
			}

			if(md_reverb) {
				if(md_reverb>15) md_reverb=15;
				MixReverb(vc_tickbuf,portion);
			}

			if(vc_mode & DMODE_FLOAT)
				Mix32toFP((float*)buffer,vc_tickbuf,portion);
			else if(vc_mode & DMODE_16BITS)
				Mix32to16((SWORD*)buffer,vc_tickbuf,portion);
			else
				Mix32to8((SBYTE*)buffer,vc_tickbuf,portion);

			buffer += samples2bytes(portion) / SAMPLING_FACTOR;
			left   -= portion;
		}
	}
}

BOOL VC2_Init(void)
{
	VC_SetupPointers();
	
	if (!(md_mode&DMODE_HQMIXER))
		return VC1_Init();
	
	if(!(Samples=(SWORD**)_mm_calloc(MAXSAMPLEHANDLES,sizeof(SWORD*)))) {
		_mm_errno = MMERR_INITIALIZING_MIXER;
		return 1;
	}
	if(!vc_tickbuf)
		if(!(vc_tickbuf=(SLONG*)_mm_malloc((TICKLSIZE+32)*sizeof(SLONG)))) {
			_mm_errno = MMERR_INITIALIZING_MIXER;
			return 1;
		}

	if(md_mode & DMODE_STEREO) {
		Mix32toFP  = Mix32ToFP_Stereo;
		Mix32to16  = Mix32To16_Stereo;
		Mix32to8   = Mix32To8_Stereo;
		MixReverb  = MixReverb_Stereo;
	} else {
		Mix32toFP  = Mix32ToFP_Normal;
		Mix32to16  = Mix32To16_Normal;
		Mix32to8   = Mix32To8_Normal;
		MixReverb  = MixReverb_Normal;
	}
	md_mode |= DMODE_INTERP;
	vc_mode = md_mode;
	return 0;
}

BOOL VC2_PlayStart(void)
{
	md_mode|=DMODE_INTERP;

	samplesthatfit = TICKLSIZE;
	if(vc_mode & DMODE_STEREO) samplesthatfit >>= 1;
	tickleft = 0;

	RVc1 = (5000L * md_mixfreq) / (REVERBERATION * 10);
	RVc2 = (5078L * md_mixfreq) / (REVERBERATION * 10);
	RVc3 = (5313L * md_mixfreq) / (REVERBERATION * 10);
	RVc4 = (5703L * md_mixfreq) / (REVERBERATION * 10);
	RVc5 = (6250L * md_mixfreq) / (REVERBERATION * 10);
	RVc6 = (6953L * md_mixfreq) / (REVERBERATION * 10);
	RVc7 = (7813L * md_mixfreq) / (REVERBERATION * 10);
	RVc8 = (8828L * md_mixfreq) / (REVERBERATION * 10);

	if(!(RVbufL1=(SLONG*)_mm_calloc((RVc1+1),sizeof(SLONG)))) return 1;
	if(!(RVbufL2=(SLONG*)_mm_calloc((RVc2+1),sizeof(SLONG)))) return 1;
	if(!(RVbufL3=(SLONG*)_mm_calloc((RVc3+1),sizeof(SLONG)))) return 1;
	if(!(RVbufL4=(SLONG*)_mm_calloc((RVc4+1),sizeof(SLONG)))) return 1;
	if(!(RVbufL5=(SLONG*)_mm_calloc((RVc5+1),sizeof(SLONG)))) return 1;
	if(!(RVbufL6=(SLONG*)_mm_calloc((RVc6+1),sizeof(SLONG)))) return 1;
	if(!(RVbufL7=(SLONG*)_mm_calloc((RVc7+1),sizeof(SLONG)))) return 1;
	if(!(RVbufL8=(SLONG*)_mm_calloc((RVc8+1),sizeof(SLONG)))) return 1;

	if(!(RVbufR1=(SLONG*)_mm_calloc((RVc1+1),sizeof(SLONG)))) return 1;
	if(!(RVbufR2=(SLONG*)_mm_calloc((RVc2+1),sizeof(SLONG)))) return 1;
	if(!(RVbufR3=(SLONG*)_mm_calloc((RVc3+1),sizeof(SLONG)))) return 1;
	if(!(RVbufR4=(SLONG*)_mm_calloc((RVc4+1),sizeof(SLONG)))) return 1;
	if(!(RVbufR5=(SLONG*)_mm_calloc((RVc5+1),sizeof(SLONG)))) return 1;
	if(!(RVbufR6=(SLONG*)_mm_calloc((RVc6+1),sizeof(SLONG)))) return 1;
	if(!(RVbufR7=(SLONG*)_mm_calloc((RVc7+1),sizeof(SLONG)))) return 1;
	if(!(RVbufR8=(SLONG*)_mm_calloc((RVc8+1),sizeof(SLONG)))) return 1;

	RVRindex = 0;
	return 0;
}

void VC2_PlayStop(void)
{
	if(RVbufL1) free(RVbufL1);
	if(RVbufL2) free(RVbufL2);
	if(RVbufL3) free(RVbufL3);
	if(RVbufL4) free(RVbufL4);
	if(RVbufL5) free(RVbufL5);
	if(RVbufL6) free(RVbufL6);
	if(RVbufL7) free(RVbufL7);
	if(RVbufL8) free(RVbufL8);
	if(RVbufR1) free(RVbufR1);
	if(RVbufR2) free(RVbufR2);
	if(RVbufR3) free(RVbufR3);
	if(RVbufR4) free(RVbufR4);
	if(RVbufR5) free(RVbufR5);
	if(RVbufR6) free(RVbufR6);
	if(RVbufR7) free(RVbufR7);
	if(RVbufR8) free(RVbufR8);

	RVbufL1=RVbufL2=RVbufL3=RVbufL4=RVbufL5=RVbufL6=RVbufL7=RVbufL8=NULL;
	RVbufR1=RVbufR2=RVbufR3=RVbufR4=RVbufR5=RVbufR6=RVbufR7=RVbufR8=NULL;
}

BOOL VC2_SetNumVoices(void)
{
	int t;

	md_mode|=DMODE_INTERP;

	if(!(vc_softchn=md_softchn)) return 0;

	if(vinf) free(vinf);
	if(!(vinf=_mm_calloc(sizeof(VINFO),vc_softchn))) return 1;

	for(t=0;t<vc_softchn;t++) {
		vinf[t].frq=10000;
		vinf[t].pan=(t&1)?PAN_LEFT:PAN_RIGHT;
	}

	return 0;
}

/* ex:set ts=4: */