VDI raster functions

raster functions More...

Functions
void	v_get_pixel (VdiHdl, short x, short y, short *pel, short *color_idx)
void	vr_trnfm (VdiHdl, MFDB *src, MFDB *dst)
void	vro_cpyfm (VdiHdl, short mode, short pxy[], MFDB *src, MFDB *dst)
void	vrt_cpyfm (VdiHdl, short mode, short pxy[], MFDB *src, MFDB *dst, short color[])

Detailed Description

raster functions

todo: add description here

Function Documentation

void v_get_pixel	(	short	handle,
		short	x,
		short	y,
		short *	pel,
		short *	index
	)

On a device with up to 8 planes (256 simultaneously displayable colors) this function returns the value and the color index of a pixel.

Parameters

handle	Device handle
x
y
pel	pixel value [option CHECK_NULLPTR] pel may be NULL
index	color index [option CHECK_NULLPTR] index may be NULL

Since

all VDI versions (screen drivers only)

In HiColor (15 or 16 bits) pel contains the pixel value and index is usually -1.

In TrueColor pel ist the low word and index the high word of the pixel value.

References VDI_CNTRLMAX.

void vr_trnfm	(	short	handle,
		MFDB *	src,
		MFDB *	dst
	)

transforms a raster from standard format to device-specific format and vice-versa. The transformation can be "in place" which means that both MFDBs point to the same address. In this case transforming a big bitmap takes ages...

Parameters

handle	Device handle
src	pointer to the source MFDB
dst	pointer to the destination MFDB

Since

all VDI versions

References VDI_CNTRLMAX.

void vro_cpyfm	(	short	handle,
		short	mode,
		short	pxy[],
		MFDB *	src,
		MFDB *	dst
	)

copies a rectangular raster onto another rectangular raster and performs the specified logic operations. Both rasters must be in device-specific format or they must have only one plane.

Parameters

handle	Device handle
mode	logical operation 0: result=0 1: result=source and destination 2: result=source and (not destination) 3: result=source 4: result=(not source) and destination 5: result=destination (!) 6: result=source xor destination 7: result=source or destination 8: result=not (source or destination) 9: result=not (source xor destination) 10: result=not destination 11: result=source or (not destination) 12: result=not source 13: result=(not source) or destination 14: result=not (source and destination) 15: result=1
pxy	coordinates xyarr[0..3]: coordinates of the source rectangle xyarr[4..7]: coordinates of the destination rectangle
src	pointer to the source MFDB
dst	pointer to the destination MFDB

Since

all VDI versions (extended since NVDI 4.10)

If the screen (or the device specified by handle) is the source or destination of a raster operation, the MFDB structure element fd_addr should be zero!

The clipping rectangle for the destination raster is enabled only if fd_addr of the destination MFDB is zero.

The source rectangle will not be clipped (it must be within the raster area).

Note:
Usually vro_cpyfm() ignores the height and width of the destination rectangle and uses the size of the source. If you want to scale a bitmap, you have to set the most significant bit in the transfer mode (wr_mode | 0x8000). In this case vro_cpyfm() scales the bitmap according to the size of the destination rectangle. Wheter the driver is able to scale or not is returned by vq_extnd() in work_out[30] (you are only allowed to set the upper bit of the mode if it is able to).

References VDI_CNTRLMAX.

void vrt_cpyfm	(	short	handle,
		short	mode,
		short	pxy[],
		MFDB *	src,
		MFDB *	dst,
		short	color[]
	)

This function expands a monochrome raster (one plane) considering the foreground and background color and copies the raster onto the destination raster using the specified writing mode.

Parameters

handle	Device handle
mode	writing mode
pxy	coordinates xyarr[0..3]: coordinates of the source rectangle xyarr[4..7]: coordinates of the destination rectangle
src	pointer to the source MFDB
dst	pointer to the destination MFDB
color	color[0] : color index for "black" points color[1] : color index for "white" points

Since

all VDI versions

If the screen is the destination raster, fd_addr should be zero!

Note:
Usually vrt_cpyfm() ignores the height and width of the destination rectangle and uses the size of the source. If you want to scale a bitmap, you have to set the most significant bit in the transfer mode (wr_mode | 0x8000). In this case vrt_cpyfm() scales the bitmap according to the size of the destination rectangle. Wheter the driver is able to scale or not is returned by vq_extnd() in work_out[30] (you are only allowed to set the upper bit of the mode if it is able to).

References VDI_CNTRLMAX.