
Graphic Orders
BLT2UB_XD
MOTOROLA
MC68322 USER’S MANUAL
13-37
The XOFF:XMUL parameter is divided into two fields. The least-significant four bits contain
the XMUL field, which specifies the factor used to scale the unexpanded source bitmap in
the X dimension. XMUL must equal a specific value from 0–15, which represents a scaling
factor of 1–16. Only certain scaling factors are supported, as defined in Table 13-3. Values
other than those listed are ignored and no X scaling is performed.
The XOFF field occupies the four most-significant bits and indicates the number of bits to be
clipped at the left edge of the expanded source bitmap. XOFF ranges from 0–XMUL. If
XOFF is zero, no clipping occurs at the left extent, but if it is non-zero, XOFF number of bits
in the left edge of the expanded bitmap are skipped and the next bit is the first one
transferred to the destination bitmap. The YOFF:YMUL parameter is also divided into two
fields. The least-significant four bits contain the YMUL field, which specifies the factor used
to scale the unexpanded source bitmap in the Y dimension. YMUL can equal any value from
0–15, which represents a scaling factor of 1–16.
The YOFF field occupies the four most-significant bits and indicates the number of scanlines
to be clipped at the top edge of the expanded source bitmap. YOFF ranges from 0–YMUL.
If YOFF is zero, no clipping occurs at the top or bottom extent, but if it is non-zero, YOFF
number of scanlines at the top edge of the expanded bitmap are skipped and the next
scanline is the first one transferred to the destination bitmap.
Related Graphic Orders
SET_BOOL_SD
SET_UBMAP
Figure 13-21. Expanded Source, Destination
bitBLT To Unbanded Bitmap
DA
BOOL_SD USED
TO COMBINE FRAMES
EXPANDED
SOURCE BITMAP
DESTINATION UNBANDED
BITMAP
XMUL
FW
XOFF
YOFF
YMUL
SW
UNEXPANDED
SOURCE BITMAP
SA
DWU
FH
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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