VideoOverlay_RedrawWindow (changes)
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VideoOverlay
» SWI Calls
» VideoOverlay_RedrawWindow
VideoOverlay_RedrawWindow
(SWI &59CCA)
| Entry | |
|---|---|
| R0 | Overlay ID |
| R1 | Pointer to block from Wimp_RedrawWindow / Wimp_GetRectangle |
| Exit | |
|---|---|
| - | All registers preserved |
Use
The owner of the window which an overlay is attached to must call this SWI for every redraw rectangle associated with the window. Taking into account the current clipping rectangle set by VideoOverlay_SetPosition, VideoOverlay will fill the corresponding screen pixels with the correct colour in order to allow the alpha blending / TCK hardware to operate correctly. For overlays which are composited directly into the framebuffer (e.g. software fallback for Basic overlays), this will trigger the rendering to take place.
Whenever necessary, VideoOverlay will automatically call Wimp_ForceRedraw in order to request that relevant areas of the window are redrawn.
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