NAME
	BltMaskBitMapRastPort -- blit from source bitmap to destination rastport
	with masking of source image.

   SYNOPSIS
	BltMaskBitMapRastPort
	    (srcbm, srcx, srcy, destrp, destX, destY, sizeX, sizeY,
	     A0     D0    D1    A1      D2     D3     D4     D5
	     minterm, bltmask)
	     D6       A2

	void BltMaskBitMapRastPort
	     (struct BitMap *, WORD, WORD, struct RastPort *, WORD, WORD,
	      WORD, WORD, UBYTE, APTR);

   FUNCTION
	Blits from source bitmap to position specified in destination rastport
	using bltmask to determine where source overlays destination, and
	minterm to determine whether to copy the source image "as is" or
	to "invert" the sense of the source image when copying. In either
	case, blit only occurs where the mask is non-zero.

   INPUTS
	srcbm   - a pointer to the source bitmap
	srcx    - x offset into source bitmap
	srcy    - y offset into source bitmap
	destrp  - a pointer to the destination rastport
	destX   - x offset into dest rastport
	destY   - y offset into dest rastport
	sizeX   - width of blit in pixels
	sizeY   - height of blit in rows
	minterm - either (ABC|ABNC|ANBC) if copy source and blit thru mask
	          or     (ANBC)          if invert source and blit thru mask
	bltmask - pointer to the single bit-plane mask, which must be the
	          same size and dimensions as the planes of the
	          source bitmap.

   RESULT

   BUGS

   SEE ALSO
	BltBitMapRastPort() graphics/gfx.h graphics/rastport.h