[hatari-devel] Killing impact screen problem : I've found the problem

Laurent Sallafranque laurent.sallafranque at free.fr
Tue Feb 2 23:50:46 CET 2010


Hello,

I've found the problem about Killing impact screen.
It displays garbage.

The problem is linked to address $ff8265 (Horizontal scroll register) 
which is not 0.

In this case, the bitplanes are not correct.

I've tried to modify the value of " fvram_column " in the 
Videl_bitplaneToChunky call.
I've added 2.

+ Videl_bitplaneToChunky( fvram_column +2, vbpp, color );

With this, hatari displays wrong (of course) because the 4 bitplanes are 
shifted.
But in killing impact (in the game), the 4 bitplanes display correctly 
(horizontal scroll register is not 0).
The main menu picture displays wrong (scroll register =0) which is OK.

fvram_column comes from     "Uint16 *fvram = (Uint16 *) 
Atari2HostAddr(atariVideoRAM);"

#define Atari2HostAddr(a) (&STRam[a])


I don't think that adding something like the following patch is a good idea:

if (hscrolloffset !=0)
   fvram +=2;

Perhaps "atariVideoRAM" is the problem too ?


Any idea of how to correct this correctly.


Regards

Laurent




More information about the hatari-devel mailing list