NAME
        BitMapScale -- Perform raster scaling on a bit map. (V36)

   SYNOPSIS
        BitMapScale(bitScaleArgs)
                    A0

        void BitMapScale(struct bitscaleargs *);

   FUNCTION
        Scale a source bit map to a non-overlapping destination
        bit map.

   INPUTS
        bitScaleArgs - structure of parameters describing scale:
            bsa_SrcX, bsa_SrcY - origin of the source bits.
            bsa_SrcWidth, bsa_SrcHeight - number of bits to scale from in x
            and y.
            bsa_DestX, bsa_DestY - origin of the destination.
            bsa_DestWidth, bsa_DestHeight - resulting number of bits in x
            and y.  NOTE: these values are set by this function.
            bsa_XSrcFactor:bsa_XDestFactor - equivalent to the ratio
                srcWidth:destWidth, but not necessarily the same
                numbers.  Each must be in the range 1..16383.
            bsa_YSrcFactor:bsa_YDestFactor - equivalent to the ratio
                srcHeight:destHeight, but not necessarily the same
                numbers.  Each must be in the range 1..16383.
            bsa_SrcBitMap - source of the bits to scale.
            bsa_DestBitMap - destination for the bits to scale.  This had
                better be big enough!
            bsa_Flags - future scaling options.  Set it to zero!
            bsa_XDDA, bsa_YDDA - for future use.  Need not be set by user.
            bsa_Reserved1, bsa_Reserved2 - for future use.  Need not be set.

   RESULT
        The destWidth, destHeight fields are set by this function as
        described above.

   NOTES
        o   This function may use the blitter.
        o   Overlapping source and destination bit maps are not
            supported.
        o   No check is made to ensure destBitMap is big enough: use
            scalerdiv to calculate a destination dimension.

   BUGS
        o   This function does not use the HighRes Agnus 'Big Blit'
            facility. You should not use XSrcFactor == XDestFactor,
            where SrcWidth or DestWidth > 1024.

        o   Also, the blitter is used when expanding in the Y direction.
            You should not expand in the Y direction if
            ((DestX & 0xf) + DestWidth) >= 1024 pixels. (Up to 1008 pixels
            is always safe).

   SEE ALSO
        scalerdiv()  graphics/scale.h