contigsc.c

“WOLF3D--刺杀希特勒”

asm	mov	ax,[es:si]
asm	mov	WORD PTR ss:[linescale],ax	// call here to start scaling
asm	mov	si,[ds:bp+2]				// corrected top of shape for this segment
asm	add	bp,6						// next segment list

asm	mov	ax,SCREENSEG
asm	mov	es,ax
asm	mov	al,ss:[mask1]
asm	out	dx,al						// set map mask register
asm	call ss:[linescale]				// scale the segment of pixels
asm	inc	di
asm	mov	al,ss:[mask2]
asm	out	dx,al						// set map mask register
asm	call ss:[linescale]				// scale the segment of pixels
asm	inc	di
asm	mov	al,ss:[mask3]
asm	out	dx,al						// set map mask register
asm	call ss:[linescale]				// scale the segment of pixels
asm	dec	di
asm	dec	di

asm	mov	es,WORD PTR ss:[linescale+2] // segment of scaler
asm	mov	BYTE PTR es:[bx],cl			// unpatch the RETF
asm	jmp	scaletriple					// do the next segment


}


/*
=======================
=
= ScaleShape
=
= Draws a compiled shape at [scale] pixels high
=
= each vertical line of the shape has a pointer to segment data:
= 	end of segment pixel*2 (0 terminates line) used to patch rtl in scaler
= 	top of virtual line with segment in proper place
=	start of segment pixel*2, used to jsl into compiled scaler
=	<repeat>
=
= Setup for call
= --------------
= GC_MODE			read mode 1, write mode 2
= GC_COLORDONTCARE  set to 0, so all reads from video memory return 0xff
= GC_INDEX			pointing at GC_BITMASK
=
=======================
*/

static	long		longtemp;

void ScaleShape (int xcenter, int shapenum, unsigned height)
{
	t_compshape	_seg *shape;
	t_compscale far *comptable;
	unsigned	scale,srcx,stopx,tempx;
	int			t;
	unsigned	far *cmdptr;
	boolean		leftvis,rightvis;


	shape = PM_GetSpritePage (shapenum);

	scale = height>>3;						// low three bits are fractional
	if (!scale || scale>maxscale)
		return;								// too close or far away
	comptable = scaledirectory[scale];

	*(((unsigned *)&linescale)+1)=FP_SEG(comptable);	// seg of far call
	*(((unsigned *)&linecmds)+1)=(unsigned)shape;		// seg of shape

//
// scale to the left (from pixel 31 to shape->leftpix)
//
	srcx = 32;
	slinex = xcenter;
	stopx = shape->leftpix;
	cmdptr = &shape->dataofs[31-stopx];

	while ( --srcx >=stopx && slinex>0)
	{
		(unsigned)linecmds = *cmdptr--;
		if ( !(slinewidth = comptable->width[srcx]) )
			continue;

		if (slinewidth == 1)
		{
			slinex--;
			if (slinex<viewwidth)
			{
				if (wallheight[slinex] >= height)
					continue;		// obscured by closer wall
				ScaleLine ();
			}
			continue;
		}

		//
		// handle multi pixel lines
		//
		if (slinex>viewwidth)
		{
			slinex -= slinewidth;
			slinewidth = viewwidth-slinex;
			if (slinewidth<1)
				continue;		// still off the right side
		}
		else
		{
			if (slinewidth>slinex)
				slinewidth = slinex;
			slinex -= slinewidth;
		}


		leftvis = (wallheight[slinex] < height);
		rightvis = (wallheight[slinex+slinewidth-1] < height);

		if (leftvis)
		{
			if (rightvis)
				ScaleLine ();
			else
			{
				while (wallheight[slinex+slinewidth-1] >= height)
					slinewidth--;
				ScaleLine ();
			}
		}
		else
		{
			if (!rightvis)
				continue;		// totally obscured

			while (wallheight[slinex] >= height)
			{
				slinex++;
				slinewidth--;
			}
			ScaleLine ();
			break;			// the rest of the shape is gone
		}
	}


//
// scale to the right
//
	slinex = xcenter;
	stopx = shape->rightpix;
	if (shape->leftpix<31)
	{
		srcx = 31;
		cmdptr = &shape->dataofs[32-shape->leftpix];
	}
	else
	{
		srcx = shape->leftpix-1;
		cmdptr = &shape->dataofs[0];
	}
	slinewidth = 0;

	while ( ++srcx <= stopx && (slinex+=slinewidth)<viewwidth)
	{
		(unsigned)linecmds = *cmdptr++;
		if ( !(slinewidth = comptable->width[srcx]) )
			continue;

		if (slinewidth == 1)
		{
			if (slinex>=0 && wallheight[slinex] < height)
			{
				ScaleLine ();
			}
			continue;
		}

		//
		// handle multi pixel lines
		//
		if (slinex<0)
		{
			if (slinewidth <= -slinex)
				continue;		// still off the left edge

			slinewidth += slinex;
			slinex = 0;
		}
		else
		{
			if (slinex + slinewidth > viewwidth)
				slinewidth = viewwidth-slinex;
		}


		leftvis = (wallheight[slinex] < height);
		rightvis = (wallheight[slinex+slinewidth-1] < height);

		if (leftvis)
		{
			if (rightvis)
			{
				ScaleLine ();
			}
			else
			{
				while (wallheight[slinex+slinewidth-1] >= height)
					slinewidth--;
				ScaleLine ();
				break;			// the rest of the shape is gone
			}
		}
		else
		{
			if (rightvis)
			{
				while (wallheight[slinex] >= height)
				{
					slinex++;
					slinewidth--;
				}
				ScaleLine ();
			}
			else
				continue;		// totally obscured
		}
	}
}



/*
=======================
=
= SimpleScaleShape
=
= NO CLIPPING, height in pixels
=
= Draws a compiled shape at [scale] pixels high
=
= each vertical line of the shape has a pointer to segment data:
= 	end of segment pixel*2 (0 terminates line) used to patch rtl in scaler
= 	top of virtual line with segment in proper place
=	start of segment pixel*2, used to jsl into compiled scaler
=	<repeat>
=
= Setup for call
= --------------
= GC_MODE			read mode 1, write mode 2
= GC_COLORDONTCARE  set to 0, so all reads from video memory return 0xff
= GC_INDEX			pointing at GC_BITMASK
=
=======================
*/

void SimpleScaleShape (int xcenter, int shapenum, unsigned height)
{
	t_compshape	_seg *shape;
	t_compscale far *comptable;
	unsigned	scale,srcx,stopx,tempx;
	int			t;
	unsigned	far *cmdptr;
	boolean		leftvis,rightvis;


	shape = PM_GetSpritePage (shapenum);

	scale = height>>1;
	comptable = scaledirectory[scale];

	*(((unsigned *)&linescale)+1)=FP_SEG(comptable);	// seg of far call
	*(((unsigned *)&linecmds)+1)=(unsigned)shape;		// seg of shape

//
// scale to the left (from pixel 31 to shape->leftpix)
//
	srcx = 32;
	slinex = xcenter;
	stopx = shape->leftpix;
	cmdptr = &shape->dataofs[31-stopx];

	while ( --srcx >=stopx )
	{
		(unsigned)linecmds = *cmdptr--;
		if ( !(slinewidth = comptable->width[srcx]) )
			continue;

		slinex -= slinewidth;
		ScaleLine ();
	}


//
// scale to the right
//
	slinex = xcenter;
	stopx = shape->rightpix;
	if (shape->leftpix<31)
	{
		srcx = 31;
		cmdptr = &shape->dataofs[32-shape->leftpix];
	}
	else
	{
		srcx = shape->leftpix-1;
		cmdptr = &shape->dataofs[0];
	}
	slinewidth = 0;

	while ( ++srcx <= stopx )
	{
		(unsigned)linecmds = *cmdptr++;
		if ( !(slinewidth = comptable->width[srcx]) )
			continue;

		ScaleLine ();
		slinex+=slinewidth;
	}
}




//
// bit mask tables for drawing scaled strips up to eight pixels wide
//
// down here so the STUPID inline assembler doesn't get confused!
//


byte	mapmasks1[4][8] = {
{1 ,3 ,7 ,15,15,15,15,15},
{2 ,6 ,14,14,14,14,14,14},
{4 ,12,12,12,12,12,12,12},
{8 ,8 ,8 ,8 ,8 ,8 ,8 ,8} };

byte	mapmasks2[4][8] = {
{0 ,0 ,0 ,0 ,1 ,3 ,7 ,15},
{0 ,0 ,0 ,1 ,3 ,7 ,15,15},
{0 ,0 ,1 ,3 ,7 ,15,15,15},
{0 ,1 ,3 ,7 ,15,15,15,15} };

byte	mapmasks3[4][8] = {
{0 ,0 ,0 ,0 ,0 ,0 ,0 ,0},
{0 ,0 ,0 ,0 ,0 ,0 ,0 ,1},
{0 ,0 ,0 ,0 ,0 ,0 ,1 ,3},
{0 ,0 ,0 ,0 ,0 ,1 ,3 ,7} };


unsigned	wordmasks[8][8] = {
{0x0080,0x00c0,0x00e0,0x00f0,0x00f8,0x00fc,0x00fe,0x00ff},
{0x0040,0x0060,0x0070,0x0078,0x007c,0x007e,0x007f,0x807f},
{0x0020,0x0030,0x0038,0x003c,0x003e,0x003f,0x803f,0xc03f},
{0x0010,0x0018,0x001c,0x001e,0x001f,0x801f,0xc01f,0xe01f},
{0x0008,0x000c,0x000e,0x000f,0x800f,0xc00f,0xe00f,0xf00f},
{0x0004,0x0006,0x0007,0x8007,0xc007,0xe007,0xf007,0xf807},
{0x0002,0x0003,0x8003,0xc003,0xe003,0xf003,0xf803,0xfc03},
{0x0001,0x8001,0xc001,0xe001,0xf001,0xf801,0xfc01,0xfe01} };

int			slinex,slinewidth;
unsigned	far *linecmds;
long		linescale;
unsigned	maskword;