Wimp_TextOp 2
WindowManager
» SWI Calls
» Wimp_TextOp
» Wimp_TextOp (Plot Text)
Wimp_TextOp (Plot Text)
(Reason Code 2)
| Entry | |||
|---|---|---|---|
| R0 | 2 + bits (See below) | ||
| Bits | |||
| 28 | Vertically centre at the Y co-ordinate | ||
| 29 | Co-ords are relative to the window being redrawn | ||
| 30 | Vertical adjust, so baseline of characters is at same Y co-ordinate as system font | ||
| 31 | Right justify (as per R4, R5) | ||
| R1 | Pointer to null-terminated string | ||
| R2 | -1 | ||
| R3 | -1 | ||
| R4 | X co-ordinate | ||
| R5 | Y co-ordinate | ||
| Exit | |
|---|---|
| R0 | String width in OS units |
| R1 | Preserved |
| R2 | Preserved |
Use
With a reason code of 2, this call plots text on screen using the current desktop font.
Notes
Bits 30-28 are used to specify the justification of the text.
This call should be used from within a redraw loop.
Because an outline font may be used, the background colour of the font must be specified, so that the anti-aliasing colours can be set-up.
BUG: The PRMs incorrectly describe the string as “ctrl-terminated”. This is not true when using System Font, so the string must always be null-terminated.
See also
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