OS_SpriteOp 41 (changes)
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Programmer's OS Reference SWI Manuals Calls
» Part OS_SpriteOp 15 – SWI Calls
» OS_SpriteOp 41 – Read pixel colourOS
» OS_SpriteOp
» OS_SpriteOp 41 – Read pixel colour
OS_SpriteOp 41 – Read pixel colour
(SWI &2E)
| Entry | |
|---|---|
| R0 | 41 (Reason code) + Area value |
| R1 | Unused/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 |
| Exit | |
|---|---|
| R5 | Pixel colour |
| R6 | Pixel tint |
| All other registers preserved | |
Use
This call allows the colour of a sprite pixel to be read.
Notes
Coordinates are specified in pixels, with (0,0) being the bottom-left corner of the sprite.
For 256 colour sprites which lack a full palette, R5 will contain the pixel colour/palette index (0-63) and R6 the tint value (0, 64, 128 or 192).
For all other sprites, R5 will be the pixel colour/palette index and R6 will be zero.
See also
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