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Old 31 March 2021, 20:56   #269
Toni Wilen
WinUAE developer
 
Join Date: Aug 2001
Location: Hämeenlinna/Finland
Age: 49
Posts: 26,517
No update yet available but just a note that Prometheus Voodoo 3 driver works after byteswap fix but it also has odd bug:

if mode is 8-bit, when blitting icons (and probably also other image elements) it tells Voodoo blitter to blit x*1 size region in host to screen mode (=blitter's source is host CPU) and then it unexpectedly writes multiple rows of data.

Voodoo documentation only says "If more data is written to the launch area than is required for the host blt specified, the extra data will be discarded, or may be used in the following host blt, if it is requested while the 2D is operating on the first hblt"

All rows (except last) must be blitted or icons are not correct. It seems blitter pushes the data to display when line is complete and next line's first word arrives and blit was supposedly already finished.

Last line needs to be skipped because there is another driver bug:

It has off by one bug in font blit routine, one extra row is blitted and if it is blitted to screen, there is garbage line below the font..

This needs annoying workaround to blitter code..

Every bridge hardware manufacturer appearently needed to code their own Voodoo driver from scratch because every driver works very differently, with different kind of weird behavior.. Only Amiga makes it possible. Again.)
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