id_vl.c

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*/

void VL_TestPaletteSet (void)
{
	int	i;

	for (i=0;i<768;i++)
		palette1[0][i] = i;

	fastpalette = true;
	VL_SetPalette (&palette1[0][0]);
	VL_GetPalette (&palette2[0][0]);
	if (_fmemcmp (&palette1[0][0],&palette2[0][0],768))
		fastpalette = false;
}


/*
==================
=
= VL_ColorBorder
=
==================
*/

void VL_ColorBorder (int color)
{
	_AH=0x10;
	_AL=1;
	_BH=color;
	geninterrupt (0x10);
	bordercolor = color;
}



/*
=============================================================================

							PIXEL OPS

=============================================================================
*/

byte	pixmasks[4] = {1,2,4,8};
byte	leftmasks[4] = {15,14,12,8};
byte	rightmasks[4] = {1,3,7,15};


/*
=================
=
= VL_Plot
=
=================
*/

void VL_Plot (int x, int y, int color)
{
	byte mask;

	mask = pixmasks[x&3];
	VGAMAPMASK(mask);
	*(byte far *)MK_FP(SCREENSEG,bufferofs+(ylookup[y]+(x>>2))) = color;
	VGAMAPMASK(15);
}


/*
=================
=
= VL_Hlin
=
=================
*/

void VL_Hlin (unsigned x, unsigned y, unsigned width, unsigned color)
{
	unsigned		xbyte;
	byte			far *dest;
	byte			leftmask,rightmask;
	int				midbytes;

	xbyte = x>>2;
	leftmask = leftmasks[x&3];
	rightmask = rightmasks[(x+width-1)&3];
	midbytes = ((x+width+3)>>2) - xbyte - 2;

	dest = MK_FP(SCREENSEG,bufferofs+ylookup[y]+xbyte);

	if (midbytes<0)
	{
	// all in one byte
		VGAMAPMASK(leftmask&rightmask);
		*dest = color;
		VGAMAPMASK(15);
		return;
	}

	VGAMAPMASK(leftmask);
	*dest++ = color;

	VGAMAPMASK(15);
	_fmemset (dest,color,midbytes);
	dest+=midbytes;

	VGAMAPMASK(rightmask);
	*dest = color;

	VGAMAPMASK(15);
}


/*
=================
=
= VL_Vlin
=
=================
*/

void VL_Vlin (int x, int y, int height, int color)
{
	byte	far *dest,mask;

	mask = pixmasks[x&3];
	VGAMAPMASK(mask);

	dest = MK_FP(SCREENSEG,bufferofs+ylookup[y]+(x>>2));

	while (height--)
	{
		*dest = color;
		dest += linewidth;
	}

	VGAMAPMASK(15);
}


/*
=================
=
= VL_Bar
=
=================
*/

void VL_Bar (int x, int y, int width, int height, int color)
{
	byte	far *dest;
	byte	leftmask,rightmask;
	int		midbytes,linedelta;

	leftmask = leftmasks[x&3];
	rightmask = rightmasks[(x+width-1)&3];
	midbytes = ((x+width+3)>>2) - (x>>2) - 2;
	linedelta = linewidth-(midbytes+1);

	dest = MK_FP(SCREENSEG,bufferofs+ylookup[y]+(x>>2));

	if (midbytes<0)
	{
	// all in one byte
		VGAMAPMASK(leftmask&rightmask);
		while (height--)
		{
			*dest = color;
			dest += linewidth;
		}
		VGAMAPMASK(15);
		return;
	}

	while (height--)
	{
		VGAMAPMASK(leftmask);
		*dest++ = color;

		VGAMAPMASK(15);
		_fmemset (dest,color,midbytes);
		dest+=midbytes;

		VGAMAPMASK(rightmask);
		*dest = color;

		dest+=linedelta;
	}

	VGAMAPMASK(15);
}

/*
============================================================================

							MEMORY OPS

============================================================================
*/

/*
=================
=
= VL_MemToLatch
=
=================
*/

void VL_MemToLatch (byte far *source, int width, int height, unsigned dest)
{
	unsigned	count;
	byte	plane,mask;

	count = ((width+3)/4)*height;
	mask = 1;
	for (plane = 0; plane<4 ; plane++)
	{
		VGAMAPMASK(mask);
		mask <<= 1;

asm	mov	cx,count
asm mov ax,SCREENSEG
asm mov es,ax
asm	mov	di,[dest]
asm	lds	si,[source]
asm	rep movsb
asm mov	ax,ss
asm	mov	ds,ax

		source+= count;
	}
}


//===========================================================================


/*
=================
=
= VL_MemToScreen
=
= Draws a block of data to the screen.
=
=================
*/

void VL_MemToScreen (byte far *source, int width, int height, int x, int y)
{
	byte    far *screen,far *dest,mask;
	int		plane;

	width>>=2;
	dest = MK_FP(SCREENSEG,bufferofs+ylookup[y]+(x>>2) );
	mask = 1 << (x&3);

	for (plane = 0; plane<4; plane++)
	{
		VGAMAPMASK(mask);
		mask <<= 1;
		if (mask == 16)
			mask = 1;

		screen = dest;
		for (y=0;y<height;y++,screen+=linewidth,source+=width)
			_fmemcpy (screen,source,width);
	}
}

//==========================================================================


/*
=================
=
= VL_MaskedToScreen
=
= Masks a block of main memory to the screen.
=
=================
*/

void VL_MaskedToScreen (byte far *source, int width, int height, int x, int y)
{
	byte    far *screen,far *dest,mask;
	byte	far *maskptr;
	int		plane;

	width>>=2;
	dest = MK_FP(SCREENSEG,bufferofs+ylookup[y]+(x>>2) );
//	mask = 1 << (x&3);

//	maskptr = source;

	for (plane = 0; plane<4; plane++)
	{
		VGAMAPMASK(mask);
		mask <<= 1;
		if (mask == 16)
			mask = 1;

		screen = dest;
		for (y=0;y<height;y++,screen+=linewidth,source+=width)
			_fmemcpy (screen,source,width);
	}
}

//==========================================================================

/*
=================
=
= VL_LatchToScreen
=
=================
*/

void VL_LatchToScreen (unsigned source, int width, int height, int x, int y)
{
	VGAWRITEMODE(1);
	VGAMAPMASK(15);

asm	mov	di,[y]				// dest = bufferofs+ylookup[y]+(x>>2)
asm	shl	di,1
asm	mov	di,[WORD PTR ylookup+di]
asm	add	di,[bufferofs]
asm	mov	ax,[x]
asm	shr	ax,2
asm	add	di,ax

asm	mov	si,[source]
asm	mov	ax,[width]
asm	mov	bx,[linewidth]
asm	sub	bx,ax
asm	mov	dx,[height]
asm	mov	cx,SCREENSEG
asm	mov	ds,cx
asm	mov	es,cx

drawline:
asm	mov	cx,ax
asm	rep movsb
asm	add	di,bx
asm	dec	dx
asm	jnz	drawline

asm	mov	ax,ss
asm	mov	ds,ax

	VGAWRITEMODE(0);
}


//===========================================================================

#if 0

/*
=================
=
= VL_ScreenToScreen
=
=================
*/

void VL_ScreenToScreen (unsigned source, unsigned dest,int width, int height)
{
	VGAWRITEMODE(1);
	VGAMAPMASK(15);

asm	mov	si,[source]
asm	mov	di,[dest]
asm	mov	ax,[width]
asm	mov	bx,[linewidth]
asm	sub	bx,ax
asm	mov	dx,[height]
asm	mov	cx,SCREENSEG
asm	mov	ds,cx
asm	mov	es,cx

drawline:
asm	mov	cx,ax
asm	rep movsb
asm	add	si,bx
asm	add	di,bx
asm	dec	dx
asm	jnz	drawline

asm	mov	ax,ss
asm	mov	ds,ax

	VGAWRITEMODE(0);
}


#endif

/*
=============================================================================

						STRING OUTPUT ROUTINES

=============================================================================
*/




/*
===================
=
= VL_DrawTile8String
=
===================
*/

void VL_DrawTile8String (char *str, char far *tile8ptr, int printx, int printy)
{
	int		i;
	unsigned	far *dest,far *screen,far *src;

	dest = MK_FP(SCREENSEG,bufferofs+ylookup[printy]+(printx>>2));

	while (*str)
	{
		src = (unsigned far *)(tile8ptr + (*str<<6));
		// each character is 64 bytes

		VGAMAPMASK(1);
		screen = dest;
		for (i=0;i<8;i++,screen+=linewidth)
			*screen = *src++;
		VGAMAPMASK(2);
		screen = dest;
		for (i=0;i<8;i++,screen+=linewidth)
			*screen = *src++;
		VGAMAPMASK(4);
		screen = dest;
		for (i=0;i<8;i++,screen+=linewidth)
			*screen = *src++;
		VGAMAPMASK(8);
		screen = dest;
		for (i=0;i<8;i++,screen+=linewidth)
			*screen = *src++;

		str++;
		printx += 8;
		dest+=2;
	}
}



/*
===================
=
= VL_DrawLatch8String
=
===================
*/

void VL_DrawLatch8String (char *str, unsigned tile8ptr, int printx, int printy)
{
	int		i;
	unsigned	src,dest;

	dest = bufferofs+ylookup[printy]+(printx>>2);

	VGAWRITEMODE(1);
	VGAMAPMASK(15);

	while (*str)
	{
		src = tile8ptr + (*str<<4);		// each character is 16 latch bytes

asm	mov	si,[src]
asm	mov	di,[dest]
asm	mov	dx,[linewidth]

asm	mov	ax,SCREENSEG
asm	mov	ds,ax

asm	lodsw
asm	mov	[di],ax
asm	add	di,dx
asm	lodsw
asm	mov	[di],ax
asm	add	di,dx
asm	lodsw
asm	mov	[di],ax
asm	add	di,dx
asm	lodsw
asm	mov	[di],ax
asm	add	di,dx
asm	lodsw
asm	mov	[di],ax
asm	add	di,dx
asm	lodsw
asm	mov	[di],ax
asm	add	di,dx
asm	lodsw
asm	mov	[di],ax
asm	add	di,dx
asm	lodsw
asm	mov	[di],ax
asm	add	di,dx

asm	mov	ax,ss
asm	mov	ds,ax

		str++;
		printx += 8;
		dest+=2;
	}

	VGAWRITEMODE(0);
}


/*
===================
=
= VL_SizeTile8String
=
===================
*/

void VL_SizeTile8String (char *str, int *width, int *height)
{
	*height = 8;
	*width = 8*strlen(str);
}