GraphicsV 22 (changes)
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GraphicsV
» GraphicsV 22
Graphics Vector (42)
| Entry | |
|---|---|
| R0 | Pointer to coordinate array, where each entry is the following 3-word structure: |
| Word 0: Head number | |
| Word 1: X position | |
| Word 2: Y position | |
| R1 | Number of entries in coordinate array |
| R2 | Bank to display (ignored if R1=0) |
| R4 | Bits 0-15: 22 (reason code) |
| Bits 16-23: Overlay number | |
| Bits 24-31: Driver number |
| Exit | |
|---|---|
| R4 | 0 |
| - | All other registers preserved |
Use
Displays or hides an overlay. The coordinate space is that of logical screen coordinates, i.e. (0,0) is the top-left corner of the screen from the viewer’s perspective (if the screen is rotated, (0,0) is still the top-left). Within that coordinate space, the coordinates specify the top-left corner of the overlay, as it appears on screen (e.g. if the overlay is rotated 180 degrees then it would actually correspond to the bottom-right pixel of the buffer).
The overlay will only appear on the heads which are included in the list. Therefore Therefore, you can hide the overlay completely by specifying R1=0.
See also
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