Copy MFDB Opaque
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VOID vro_cpyfrm(handle, mode, location, source, destination)
WORD handle, mode;
WORD *pxy;
MFDB *source, *destination

	Handle specifies a valid VDI workstation handle. Mode specifies the copy 
	mode as follows..
	

	Mode		Operation
	0               destination = 0	
	1               destination = source AND destination		
	2               destination = source !AND destination 
	3               destination = source			
	4               destination = !source AND destination
	5               destination = destination			
	6               destination = source XOR destination		
	7               destination = source OR destination		
	8               destination = !(source OR destination)
	9               destination = !(source XOR destination)
	10              destination = !destination 
	11              destination = source OR !destination 
	12              destination = !source
	13		destination = !source OR destination
	14              destination = !(source AND destination)
	15              destination = 1	
	
	location is a eight WORD array. Location[0-3] contain a VDI bounding 
	rectangle for the source (i.e. what part of the source bitmap is to be 
	copied) and location[4-7] are the destination bounding box i.e. where 
	the section is copied to in the destination. Note the use of this array 
	when copying to or from the screen...
	
	source and destination are MFDB structures. One or both can be 0, to 
	signify the screen.
	

Copy raster transparent
-----------------------

VOID vrt_cpyfrm(handle, mode, location, source, destination, colours)
WORD handle, mode;
WORD *pxy;
MFDB *source, *destination
WORD *colours

	Handle, source, destination and pxy are as in the function above. Mode 
	in this case has only four possible values...
	
		1	Replace
		2       Transparent
		3       XOR
		4       Reverse transparent
		
	colours specifies a two word array, colours[0] defining the colour used 
	for '0' bits in the source, and colours[1] the colour used for '1' bits 
	in the source.
	
	
	
NOTE: for both these functions the bitmaps must be in ST specific form, i.e not 
VDI independant form. Therefore, you may need this function...

Transform Bitmaps
-----------------

VOID vr_trnfm(handle, source, destination)
WORD handle;
MFDB *source, *destination;

	handle is the VDIO handle, source and destination are MFDB structures. 
	Note they can be the same. The function will not increase or reduce 
	colour depths of the bitmaps.
	
	Note that, especially for large, many coloured bitmaps, this function is 
	quite slow.