kdmeng.c

小型游戏引擎

		frqeff[chanum] = 0; frqoff[chanum] = 0;
		voleff[chanum] = 0; voloff[chanum] = 0;
		paneff[chanum] = 0; panoff[chanum] = 0;
		return;
	}
}

void getsndbufinfo(long *dasndoffsplc, long *dasndbufsiz)
{
	*dasndoffsplc = sndoffsplc;
	*dasndbufsiz = (sndbufsiz<<(bytespersample+numspeakers-2));
}

void preparesndbuf(void)
{
	long i, j, k, voloffs1, voloffs2, *stempptr;
	long daswave, dasinc, dacnt;
	long ox, oy, x, y;
	//char *sndptr, v1, v2;

	kdmintinprep++;
	if (kdminprep != 0) return;

	if ((digistat == 1) || (digistat == 2))
	{
		i = kinp(dmacheckport); i += (kinp(dmacheckport)<<8);
		if (i <= dmachecksiz)
		{
			i = ((i > 32) && (i <= (dmachecksiz>>1)+32));
			if ((sndoffsplc<(sndoffsplc^sndoffsxor)) == i) kdmintinprep++;
		}
	}

	kdminprep = 1;
	while (kdmintinprep > 0)
	{
		sndoffsplc ^= sndoffsxor;

		for (i=NUMCHANNELS-1;i>=0;i--)
			if ((splc[i] < 0) && (chanstat[i] > 0))
			{
				if (chanstat[i] == 1)
				{
					ox = xplc[i];
					oy = yplc[i];
				}
				else
				{
					stempptr = (long *)xplc[i]; ox = *stempptr;
					stempptr = (long *)yplc[i]; oy = *stempptr;
				}
				ox -= globposx; oy -= globposy;
				x = dmulscale28(oy,globxvect,-ox,globyvect);
				y = dmulscale28(ox,globxvect,oy,globyvect);

				if ((klabs(x) >= 32768) || (klabs(y) >= 32768))
					{ splc[i] = 0; continue; }

				j = vdist[i];
				vdist[i] = msqrtasm(x*x+y*y);
				if (j)
				{
					j = (sinc[i]<<10)/(min(max(vdist[i]-j,-768),768)+1024)-sinc[i];
					sincoffs[i] = ((sincoffs[i]*7+j)>>3);
				}

				voloffs1 = min((vol[i]<<22)/(((x+1536)*(x+1536)+y*y)+1),255);
				voloffs2 = min((vol[i]<<22)/(((x-1536)*(x-1536)+y*y)+1),255);

				if (numspeakers == 1)
					calcvolookupmono(FP_OFF(volookup)+(i<<(9+2)),-(voloffs1+voloffs2)<<6,(voloffs1+voloffs2)>>1);
				else
					calcvolookupstereo(FP_OFF(volookup)+(i<<(9+2)),-(voloffs1<<7),voloffs1,-(voloffs2<<7),voloffs2);
			}

		for(dacnt=0;dacnt<sndbufsiz;dacnt+=bytespertic)
		{
			if (musicstatus > 0)    //Gets here 120 times/second
			{
				while ((notecnt < numnotes) && (timecount >= nttime[notecnt]))
				{
					j = trinst[nttrack[notecnt]];
					k = mulscale24(frqtable[ntfreq[notecnt]],finetune[j]+748);

					if (ntvol1[notecnt] == 0)   //Note off
					{
						for(i=NUMCHANNELS-1;i>=0;i--)
							if (splc[i] < 0)
								if (swavenum[i] == j)
									if (sinc[i] == k)
										splc[i] = 0;
					}
					else                        //Note on
						startwave(j,k,ntvol1[notecnt],ntvol2[notecnt],ntfrqeff[notecnt],ntvoleff[notecnt],ntpaneff[notecnt]);

					notecnt++;
					if (notecnt >= numnotes)
						if (musicrepeat > 0)
							notecnt = 0, timecount = nttime[0];
				}
				timecount++;
			}

			for(i=NUMCHANNELS-1;i>=0;i--)
			{
				if (splc[i] >= 0) continue;

				dasinc = sinc[i]+sincoffs[i];

				if (frqeff[i] != 0)
				{
					dasinc = mulscale16(dasinc,eff[frqeff[i]-1][frqoff[i]]);
					frqoff[i]++; if (frqoff[i] >= 256) frqeff[i] = 0;
				}
				if ((voleff[i]) || (paneff[i]))
				{
					voloffs1 = svol1[i];
					voloffs2 = svol2[i];
					if (voleff[i])
					{
						voloffs1 = mulscale16(voloffs1,eff[voleff[i]-1][voloff[i]]);
						voloffs2 = mulscale16(voloffs2,eff[voleff[i]-1][voloff[i]]);
						voloff[i]++; if (voloff[i] >= 256) voleff[i] = 0;
					}

					if (numspeakers == 1)
						calcvolookupmono(FP_OFF(volookup)+(i<<(9+2)),-(voloffs1+voloffs2)<<6,(voloffs1+voloffs2)>>1);
					else
					{
						if (paneff[i])
						{
							voloffs1 = mulscale16(voloffs1,131072-eff[paneff[i]-1][panoff[i]]);
							voloffs2 = mulscale16(voloffs2,eff[paneff[i]-1][panoff[i]]);
							panoff[i]++; if (panoff[i] >= 256) paneff[i] = 0;
						}
						calcvolookupstereo(FP_OFF(volookup)+(i<<(9+2)),-(voloffs1<<7),voloffs1,-(voloffs2<<7),voloffs2);
					}
				}

				daswave = swavenum[i];
				voloffs1 = FP_OFF(volookup)+(i<<(9+2));

				kdmasm1 = repleng[daswave];
				kdmasm2 = wavoffs[daswave]+repstart[daswave]+repleng[daswave];
				kdmasm3 = (repleng[daswave]<<12); //repsplcoff
				kdmasm4 = soff[i];
				if (numspeakers == 1)
				{
					if (kdmqual == 0) splc[i] = monolocomb(0L,voloffs1,bytespertic,dasinc,splc[i],FP_OFF(stemp));
									 else splc[i] = monohicomb(0L,voloffs1,bytespertic,dasinc,splc[i],FP_OFF(stemp));
				}
				else
				{
					if (kdmqual == 0) splc[i] = stereolocomb(0L,voloffs1,bytespertic,dasinc,splc[i],FP_OFF(stemp));
									 else splc[i] = stereohicomb(0L,voloffs1,bytespertic,dasinc,splc[i],FP_OFF(stemp));
				}
				soff[i] = kdmasm4;

				if ((kdmqual == 0) || (splc[i] >= 0)) continue;
				if (numspeakers == 1)
				{
					if (kdmqual == 0) monolocomb(0L,voloffs1,samplerate>>11,dasinc,splc[i],FP_OFF(stemp)+(bytespertic<<2));
									 else monohicomb(0L,voloffs1,samplerate>>11,dasinc,splc[i],FP_OFF(stemp)+(bytespertic<<2));
				}
				else
				{
					if (kdmqual == 0) stereolocomb(0L,voloffs1,samplerate>>11,dasinc,splc[i],FP_OFF(stemp)+(bytespertic<<3));
									 else stereohicomb(0L,voloffs1,samplerate>>11,dasinc,splc[i],FP_OFF(stemp)+(bytespertic<<3));
				}
			}

			if (kdmqual)
			{
				if (numspeakers == 1)
				{
					for(i=(samplerate>>11)-1;i>=0;i--)
						stemp[i] += mulscale16(stemp[i+1024]-stemp[i],ramplookup[i]);
					j = bytespertic; k = (samplerate>>11);
					copybuf(&stemp[j],&stemp[1024],k);
					clearbuf(&stemp[j],k,32768);
				}
				else
				{
					for(i=(samplerate>>11)-1;i>=0;i--)
					{
						j = (i<<1);
						stemp[j+0] += mulscale16(stemp[j+1024]-stemp[j+0],ramplookup[i]);
						stemp[j+1] += mulscale16(stemp[j+1025]-stemp[j+1],ramplookup[i]);
					}
					j = (bytespertic<<1); k = ((samplerate>>11)<<1);
					copybuf(&stemp[j],&stemp[1024],k);
					clearbuf(&stemp[j],k,32768);
				}
			}

			if (numspeakers == 1)
			{
				if (bytespersample == 1)
				{
					if (digistat == 13) pcbound2char(bytespertic>>1,FP_OFF(stemp),sndoffsplc+dacnt);
										  else bound2char(bytespertic>>1,FP_OFF(stemp),sndoffsplc+dacnt);
				} else bound2short(bytespertic>>1,FP_OFF(stemp),sndoffsplc+(dacnt<<1));
			}
			else
			{
				if (bytespersample == 1) bound2char(bytespertic,FP_OFF(stemp),sndoffsplc+(dacnt<<1));
										 else bound2short(bytespertic,FP_OFF(stemp),sndoffsplc+(dacnt<<2));
			}
		}
		kdmintinprep--;
	}
	kdminprep = 0;
}

void wsay(char *dafilename, long dafreq, long volume1, long volume2)
{
	unsigned char ch1, ch2;
	long i, j, bad;

	if (digistat == 0) return;

	i = numwaves-1;
	do
	{
		bad = 0;

		j = 0;
		while ((dafilename[j] > 0) && (j < 16))
		{
			ch1 = dafilename[j]; if ((ch1 >= 97) && (ch1 <= 123)) ch1 -= 32;
			ch2 = instname[i][j]; if ((ch2 >= 97) && (ch2 <= 123)) ch2 -= 32;
			if (ch1 != ch2) {bad = 1; break;}
			j++;
		}
		if (bad == 0)
		{
			startwave(i,(dafreq*11025)/samplerate,volume1,volume2,0L,0L,0L);
			return;
		}

		i--;
	} while (i >= 0);
}

void loadwaves(char *wavename)
{
	long fil, i, j, dawaversionum;
	char filename[80];

	strcpy(filename,wavename);
	if (strstr(filename,".KWV") == 0) strcat(filename,".KWV");
	if ((fil = kopen4load(filename,0)) == -1)
		if (strcmp(filename,"WAVES.KWV") != 0)
		{
			strcpy(filename,"WAVES.KWV");
			fil = kopen4load(filename,0);
		}

	totsndbytes = 0;

	if (fil != -1)
	{
		if (strcmp(kwvname,filename) == 0) { kclose(fil); return; }
		strcpy(kwvname,filename);

		kread(fil,&dawaversionum,4);
		if (dawaversionum != 0) { kclose(fil); return; }

		kread(fil,&numwaves,4);
		for(i=0;i<numwaves;i++)
		{
			kread(fil,&instname[i][0],16);
			kread(fil,&wavleng[i],4);
			kread(fil,&repstart[i],4);
			kread(fil,&repleng[i],4);
			kread(fil,&finetune[i],4);
			wavoffs[i] = totsndbytes;
			totsndbytes += wavleng[i];
		}
	}
	else
	{
		dawaversionum = 0;
		numwaves = 0;
	}

	for(i=numwaves;i<MAXWAVES;i++)
	{
		for(j=0;j<16;j++) instname[i][j] = 0;
		wavoffs[i] = totsndbytes;
		wavleng[i] = 0L;
		repstart[i] = 0L;
		repleng[i] = 0L;
		finetune[i] = 0L;
	}

	if (snd == 0)
	{
		if ((snd = (char *)malloc(totsndbytes+2)) == 0)
			{ printf("Not enough memory for digital music!\n"); exit(0); }
	}
	for(i=0;i<MAXWAVES;i++) wavoffs[i] += FP_OFF(snd);
	if (fil != -1)
	{
		kread(fil,snd,totsndbytes);
		kclose(fil);
	}
	snd[totsndbytes] = snd[totsndbytes+1] = 128;
}

int loadsong(char *filename)
{
	long /*i,*/ fil;

	if (musistat != 1) return(0);
	musicoff();
	filename = strupr(filename);
	if (strstr(filename,".KDM") == 0) strcat(filename,".KDM");
	if ((fil = kopen4load(filename,0)) == -1)
	{
		printf("I cannot load %s.\n",filename);
		uninitsb();
		return(-1);
	}
	kread(fil,&kdmversionum,4);
	if (kdmversionum != 0) return(-2);
	kread(fil,&numnotes,4);
	kread(fil,&numtracks,4);
	kread(fil,trinst,numtracks);
	kread(fil,trquant,numtracks);
	kread(fil,trvol1,numtracks);
	kread(fil,trvol2,numtracks);
	kread(fil,nttime,numnotes<<2);
	kread(fil,nttrack,numnotes);
	kread(fil,ntfreq,numnotes);
	kread(fil,ntvol1,numnotes);
	kread(fil,ntvol2,numnotes);
	kread(fil,ntfrqeff,numnotes);
	kread(fil,ntvoleff,numnotes);
	kread(fil,ntpaneff,numnotes);
	kclose(fil);
	return(0);
}

void musicon(void)
{
	if (musistat != 1)
		return;

	notecnt = 0;
	timecount = nttime[notecnt];
	musicrepeat = 1;
	musicstatus = 1;
}

void musicoff(void)
{
	long i;

	musicstatus = 0;
	for(i=0;i<NUMCHANNELS;i++)
		splc[i] = 0;
	musicrepeat = 0;
	timecount = 0;
	notecnt = 0;
}

kdmconvalloc32 (long size)
{
#ifdef PLATFORM_DOS	
	union REGS r;

	r.x.eax = 0x0100;           //DPMI allocate DOS memory
	r.x.ebx = ((size+15)>>4);   //Number of paragraphs requested
	int386(0x31,&r,&r);

	if (r.x.cflag != 0)         //Failed
		return ((long)0);
	return ((long)((r.x.eax&0xffff)<<4));   //Returns full 32-bit offset
#else
	fprintf (stderr, "%s line %d; kdmconvalloc32() called\n", __FILE__,
		__LINE__);
#endif	
}

installbikdmhandlers()
{
#ifdef PLATFORM_DOS	
	union REGS r;
	struct SREGS sr;
	long lowp;
	void far *fh;

		//Get old protected mode handler
	r.x.eax = 0x3500+kdmvect;   /* DOS get vector (INT 0Ch) */
	sr.ds = sr.es = 0;
	int386x(0x21,&r,&r,&sr);
	kdmpsel = (unsigned short)sr.es;
	kdmpoff = r.x.ebx;

		//Get old real mode handler
	r.x.eax = 0x0200;   /* DPMI get real mode vector */
	r.h.bl = kdmvect;
	int386(0x31,&r,&r);
	kdmrseg = (unsigned short)r.x.ecx;
	kdmroff = (unsigned short)r.x.edx;


		//Allocate memory in low memory to store real mode handler
	if ((lowp = kdmconvalloc32(KDMCODEBYTES)) == 0)
	{
		printf("Can't allocate conventional memory.\n");
		exit;
	}
	memcpy((void *)lowp,(void *)pcrealbuffer,KDMCODEBYTES);

		//Set new protected mode handler
	r.x.eax = 0x2500+kdmvect;   /* DOS set vector (INT 0Ch) */
	fh = (void far *)pctimerhandler;
	r.x.edx = FP_OFF(fh);
	sr.ds = FP_SEG(fh);      //DS:EDX == &handler
	sr.es = 0;
	int386x(0x21,&r,&r,&sr);

		//Set new real mode handler (must be after setting protected mode)
	r.x.eax = 0x0201;
	r.h.bl = kdmvect;              //CX:DX == real mode &handler
	r.x.ecx = ((lowp>>4)&0xffff);  //D32realseg
	r.x.edx = 0L;                  //D32realoff
	int386(0x31,&r,&r);
#else
	fprintf(stderr,"%s line %d; installbikdmhandlers() called\n", __FILE__,
		__LINE__);
#endif	
}

uninstallbikdmhandlers()
{
#ifdef PLATFORM_DOS	
	union REGS r;
	struct SREGS sr;

		//restore old protected mode handler
	r.x.eax = 0x2500+kdmvect;   /* DOS set vector (INT 0Ch) */
	r.x.edx = kdmpoff;
	sr.ds = kdmpsel;    /* DS:EDX == &handler */
	sr.es = 0;
	int386x(0x21,&r,&r,&sr);

		//restore old real mode handler
	r.x.eax = 0x0201;   /* DPMI set real mode vector */
	r.h.bl = kdmvect;
	r.x.ecx = (unsigned long)kdmrseg;     //CX:DX == real mode &handler
	r.x.edx = (unsigned long)kdmroff;
	int386(0x31,&r,&r);
#else
	fprintf(stderr,"%s line %d; uninstallbikdmhandlers() called\n",
		__FILE__, __LINE__);
#endif	
}