Integer scaling not pixel-perfect in 2.3.3 and 2.4.0 beta 21

[Bonifacy]

I do not get a pixel-perfect integer scaling. I have attached two screen shots (no scaling and 2x scaling comparison) and the logs for beta 22. The second one has clearly visible artifacts - the most prominent being a diagonal tear line.

The artifacts for 2.3.3 not exactly the same, but very similar (diagonal line included).

I have disabled all GPU controlling software and changed all possible settings in display driver to "Application Controlled". I have an ATI card.

Also a separate confirmation can be found here:
http://eab.abime.net/showpost.php?p=...&postcount=299

[Toni Wilen]

This diagonal line appears in some filter settings, I have seen it myself but I am no sure where it comes from, probably texel center position is not calculated correctly but this is stuff I am not that familiar..

[Bonifacy]

Originally Posted by Toni Wilen

This diagonal line appears in some filter settings, I have seen it myself but I am no sure where it comes from, probably texel center position is not calculated correctly but this is stuff I am not that familiar..

OK.

It may be as well that pixel-exact integer scaling is not even an advertised feature of WinUAE, and this is in fact a request rather than a bug report

In any case, nevermind. A good combination of mildly smoothing filters should be enough for me and it may be even more visually pleasing than pixel-exactness.

Hi,

I think I have the same problem with the latest non-beta.

I was using Powerstrip to set my CRT monitor @50Hz refresh rate, to have smooth scrolling. It was difficult to find the right V-sync settings (the legacy V-sync is too laggy for actual gameplay on my machine, and some other settings wouldn't work smoothly) but I could eventually get everything right, except for that line.
It's a pity because except this small line, the result was smooth and pixel perfect !

I could post all my settings and even capture and upload it (w/ FRAPS) it if it can be of any help.

Regards

[Toni Wilen]

Test using latest beta. Include winuaebootlog.txt, config file and screenshot.

Do you mean low latency vsync mode isn't smooth? If yes, include low latency vsync winuaelog.txt.

I have just tried again with latest Beta 8.

1. I couldn't replicate the V-sync problem I had before, sorry about that !

2. I tried to actually record the diagonal line problem but I can't get it right. I will try my capture card later.
Anyway, I couldn't replicate the diagonal line problem with "integer scaling" alone (I can't make integer scaling work at all, probably wrong settings on my part), I had to use "automatic integer scaling" and the diagonal line can be seen live and on screenshots (see attached files). It's very hard to spot on screenshots (be sure to check the screenshots with 1:1 scale), so I have outlined it. It looks like the location of the line can vary over time.

Regards

edit: stupid typo

[Toni Wilen]

Originally Posted by Keade

I have just tried again with latest Beta 8.

It is same problem. I guess I need to take closer look. again.

[Toni Wilen]

I finally tried to debug this but I can't duplicate it, I used exact same settings, exact same resolution and exact same game.

Possibly ATI only? (Going to test using 6970 later this week)

[Dunny]

Originally Posted by Toni Wilen

I finally tried to debug this but I can't duplicate it, I used exact same settings, exact same resolution and exact same game.

Possibly ATI only? (Going to test using 6970 later this week)

FWIW, I had exactly the same problem when writing the D3D Scaler for ZXSpin - on ATI cards I got a diagonal line. Offsetting texture coordinates by 0.5 pixels fixed it, with no visible artifacts on nVidia/Intel cards.

D.

[Toni Wilen]

Originally Posted by Dunny

FWIW, I had exactly the same problem when writing the D3D Scaler for ZXSpin - on ATI cards I got a diagonal line. Offsetting texture coordinates by 0.5 pixels fixed it, with no visible artifacts on nVidia/Intel cards.

I already have 0.5 offsets like documented somewhere, really need to retest..

EDIT: Thanks for confirming that there can be differences between different manufacturers. Bleh..

[Toni Wilen]

AMD HD 6970 test done and issue confirmed.

Should be fixed in next beta.

Actually I just removed comments from "useless looking" 0.5 offsets that fixed the problem.. I thought D3D spec says texel positions should be exact same but real world, as usual, works differently..

Hi,

Confirming I was having the problem with an ATI card too (Radeon HD 5870).
Thanks for your (re)checking the issue and fixing it !