Analog vga_scaler vertical screen rotation cuts off 1/3 of image (CRT TV)

Discussion about displays and related hardware including MiSTer filters and video settings.
HappehLemons
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Analog vga_scaler vertical screen rotation cuts off 1/3 of image (CRT TV)

Unread post by HappehLemons »

Cross posting from:
viewtopic.php?f=25&t=3494

I'm running into a really strange bug (Image attached)

My setup:
I'm hooked up directly to component thru the VGA port with ypbpr=1 and vga_scaler=1
I'm using a CRT TV (Sony Trinitron)
Playing games that require vertical rotation

Issue:
Games that vertically rotate on my CRT get 1/3 of the image cut off on the right side

Using:
video_mode= 320,8,32,40,240,1,8,6,6120

I get almost get the exact result I'm looking for, but for some reason the right side is cropped off:
4HskgyE.jpg
4HskgyE.jpg (2.51 MiB) Viewed 1345 times
With:
video_mode= 640,76,60,118,240,4,1,20,14200

I get a thinner result, but the image is super thin, with the same issue of the right side is cropped off
5iasQqC.jpg
5iasQqC.jpg (1.51 MiB) Viewed 1345 times
If I switch the games to "fullscreen" they take up the whole width of the TV and the FULL IMAGE is restored properly, but the picture is the wrong ratio of course.

If I play a game that doesn't require vertical rotation the whole image is there, this only happens with vertical games.

Any ideas why this would happen?
rgavril
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Re: Analog vga_scaler vertical screen rotation cuts off 1/3 of image (CRT TV)

Unread post by rgavril »

I've bumped into same problem when trying to use the scaler to play vertical arcade on my pvm.

Looks like the scaler is calculating the a 3:4 viewport correctly (240px vertical / 180px horizontal) but it doesn't do any horizontal downscaling. That particular game in TATE mode has a horizontal resolution of 224px resulting in 224px - 180px = 44px outside of the viewport.

We probably should open an issue on github and hope it will get fixed.
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