IOP_WPAP
This SMSQ/E trap sets the wallpaper.
| Call Parameters | Return Parameters | ||
|---|---|---|---|
| D0.B | $6B | D0.L | Error code |
| D1.L | Colour code | D1.L | Preserved? |
| D2.L | Image code | D2.L | Preserved? |
| D3.W | Timeout | D3.L | Preserved. |
| A0.L | Channel ID | A0.L | Preserved. |
| A1.L | Address of Image | A1.L | Preserved. |
Errors
| ERR_NC | Not complete. |
| ERR_NO | Channel not open. |
Notes
- All registers not shown above are not used on entry and are probably preserved on exit.
- The code in D1.L has the following meanings:
- -1 if the background colour is not to be changed.
- 0 for a black background.
- 1-255 for a stippled QL colour background.
- n*256 for a 24 bit true colour background.
- The code in D2.L is -1 for no background image and 0 for an image.
- The address in A1 is only needed when D2 = 0. In this case the image to which A1 points must be a snapshot of the screen in the current mode and resolution.
Example
The example below shows the use of this trap call to set a QL colour background. It is assumed that A0 contains the ID of a valid screen channel.
wallp moveq #-1,d3 ; Timeout
moveq #119,d1 ; A QL stipple colour
moveq #-1,d2 ; No image
moveq #iop_wpap,d0 ; $6B
trap #3 ; Set the background colour
tst.l d0 ; OK? . .
bne error ; . . no!
george.gwilt