Resolution Headaches

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Atari freak
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Resolution Headaches

Post by mib5150 »

I programmed in gfabasic 3.6TT a little earlier today, and something very annoying happened.

I used the XBIOS(5)-function to go from medium to low resolution. On my first tests I let the program tell me if it did it right by printing out a string. So far so good. It looked right, I was satisfied with that, and I added som more code according to my plans... I wanted to draw filled boxes.

When I started to draw the boxes I realized that my Mega STE hadn't switched to low resolution completely. The XBIOS(4) call told me that we were in Low Resolution (0), and my PRINT-lines looked like low resolution, BUT when I draw a box 0,0,319,199 it just filled half the screen! Further tests showed that the resolution was 639x199.

Why?! I got distracted and never tried to boot the computer without NVDI, so therefore I ask here before I get back to my problem tonight: Could NVDI be the problem here?
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Location: Friedrichshafen, Germany

Re: Resolution Headaches

Post by simonsunnyboy »

The VDI is not properly reinitialized when you change the resolution with XBIOS. I can't tell about NVDI.

The workaround is to use Linea or use selfmade functions - or the proper solution is to write resolution independent VDI conform code.
Simon Sunnyboy/Paradize -

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