OS_SpriteOp 53 (changes)
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OS SWI Calls
» OS_SpriteOp
» OS_SpriteOp 53 – Put Sprite Grey Scaled
OS_SpriteOp 53 – Put Sprite Grey Scaled
(SWI &2E)
| Entry | |
|---|---|
| R0 | 53 (Reason code) + Area value |
| R1 | Sprite area (as defined by area value in R0) |
| R2 | Sprite name/pointer (as defined by area value in R0) |
| R3 | X coordinate |
| R4 | Y coordinate |
| R5 | 0 |
| R6 | Pointer to scaling factors, or 0 for 1:1 scaling |
| R7 | Pointer to pixel translation table / Colour Mapping Descriptor, or 0 for no translation |
| Exit | |
|---|---|
| All registers preserved | |
Use
This call anti-aliases a sprite as it scales it.
Notes
This reason code is not available on SpriteExtend version 0.99 and later.
The sprite must have been defined in a 16-colour mode whose pipxels refelect a linear grey scale. This is considerably slower than OS_SpriteOp 52
Coordinates are in OS units, and specify the bottom-left corner of the sprite.
1:1 scaling maps directly from source pixels to destination pixels; the DPI and eigen values of the source and destination are ignored.
See also
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