JPEG_PlotFileScaled (changes)
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Programmer's SpriteExtend Reference Manuals
» Part 11 – Sound and Video?SWI Calls
» JPEG_PlotFileScaledJPEG?
» JPEG SWI Calls
» JPEG_PlotFileScaled
JPEG_PlotFileScaled
(SWI &49983)
| Entry | |
|---|---|
| R0 | Pointer to control character terminated filename |
| R1 | X coordinate |
| R2 | Y coordinate |
| R3 | Pointer to scale factors, or 0 for 1:1 scaling |
| R4 | Flags: |
| Bit 0: Dither output | |
| Bit 1: Use full error diffused dithering | |
| Bit 3: Use colour mapping | |
| Bits 4-11: Translucency (0 = opaque, 255 = 1/256 visibility) | |
| Other bits reserved, should be zero | |
| R5 | Pointer to Colour Mapping Descriptor, if relevant |
| Exit | |
|---|---|
| - | All registers preserved |
Use
This call is used to plot a scaled JPEG image to screen.
Notes
Coordinates are in OS units, and specify the bottom-left corner of the image.
1:1 scaling maps directly from source pixels to destination pixels; the DPI and eigen values of the source and destination are ignored.
This call is effectively just a convenience wrapper around JPEG_PlotScaled.
See also
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