Re: [hatari-devel] Motion demo Susie screen

[Laurent Sallafranque <laurent.sallafranque@xxxxxxx>]

I've managed to find what I had in mind : with hatari 1.4, I get the following image :

(You have to wait 30 seconds before the image arrives, at first, the screen displays garbage and then, the effect starts.

Regards

Laurent

Le 30/11/2020 à 21:19, Laurent Sallafranque a écrit :

> I've seen
>       this Suzie demo with a previous version of hatari (it displays
>       some blue and white buildings if I remember correctly).
>       
>       
>       the demo had a problem with the screen (videl emu I think).
>       
>       
>       I'll check with previous versions of Hatari if I can let it run
>       again.
>       
>       
>       Laurent
>       
>       
>       
>       Le 30/11/2020 à 20:22, Eero Tamminen a écrit :
>       
> > Hi,
> >         
> >         
> >         On 11/1/20 4:54 PM, Nicolas Pomarède wrote:
> >         
> > > Le 27/10/2020 à 00:12, Eero Tamminen a
> > >           écrit :
> > >           
> > > > Only "Susie" doesn't work, it's now
> > > >             stuck
> > > >             
> > > >             executing these instructions:
> > > >             
> > > >                $00016690 : btst   #0,$fffffc00.w    50.00%
> > > >             
> > > >                $00016696 : beq.s  $16690            50.00%
> > > >             
> > > >             
> > > >             Nicolas, any ideas what could be the problem?
> > > >             
> > > >           
> > >           
> > >           if you look at the code after, you can see that the btst is in
> > >           fact waiting for a byte to be received from the ikbd ; which
> > >           means a key was pressed (or mouse was moved).
> > >           
> > >           then just after, it compares the content of fffc02 with #$01,
> > >           which is the scancode for the 'esc' key.
> > >           
> > >           
> > >           So, demo is not stuck ; press 'esc' and it will continue. In
> > >           fact it exits. I don't know it's supposed to run sthg instead
> > >           of exiting > someone would need to test on a real falcon.
> > >           (or look at the source code
> > >           
> > >           with the demo)
> > >           
> > >         
> >         
> >         "Susie" screen description states following:
> >         
> >         --------------------------------------------
> >         
> >         Wolfestein/doom routine. Trilinear filtering
> >         
> >         (mipmaps!) and featuring anti-aliasing of wall
> >         
> >         edges. The DSP is used just to do the 3d
> >         
> >         mathematics. Uses blitter in a funny way to read
> >         
> >         one pixel and write it twice, but this causes
> >         
> >         problems with the sound DMA. Massive pre-
> >         
> >         calculations. All wall heights are in memory.
> >         
> >         Features a nice roll effect. 2x2 pixels, but
> >         
> >         proper ultra-low resolution screen might speed
> >         
> >         it up to 50hz. Truecolor.
> >         
> >         --------------------------------------------
> >         
> >         
> >         Which corresponds to attached image (susie-pouet.png) from
> >         pouet.net.
> >         
> >         
> >         But it looks like the attached susie-hatari.png instead.
> >         
> >         
> >         Maybe the blitter stuff is one of the problems?
> >         
> >         
> >         I have no idea how that e.g. interacts with Videl emulation...
> >         
> >         
> >         
> >             - Eero
> >         
> >       
>       
>       
>