Indivision AGA MK2 issue: games show as cropped and witha lot of lines

[guybrush]

I have installed a new Indivision Aga MK2 on my A1200, and noticed pretty bad output in PAL mode. At boot, the video look quite bad, with a visible black border, that has a ton of lines, both on the border and on the actual image.


https://ibb.co/sRr508w


https://ibb.co/Nm1wggB




Once it load Workbench, it looks fine; the screen is set to be a 1280x1024 at 60Hz. But when I run games or demos, the screen shrink, and you can see those ugly borders and black lines. How do I fix this?



I thought it was a matter of the card not sitting correctly on the chip, so I pressed it to be sure it is sitting correctly. I posted some pictures to show the difference between standard PAL mode and the WB mode.


Also the Indivision tool to set up the screen is probably the hardest thing I had to deal with in my life; it is hard to make sense of how to set it up, because the screen size and the actual monitor resolution size do not match at all.

[guybrush]

Ok, I figured this out...really whoever wrote the indivision software should take some UI classes
Basically the left side of the tool show the "amiga mode"; that means whatever the normal output of the amiga would be. The right side show the actual resolution. So I noticed that my config had "pal" amiga mode on the left to be 1024x768@60Hz; which should be totally fine, but the video mode on my DVI monitor look like the picture I posted in the thread.
I changed it to 640x480 and now the screen is stretched, so now the image when I play demos and games, is fully stretched, exactly like when I use the 1280x1024 workbench mode.

Why is that? Who knows; I just went through all the various resolutions for PAL mode until I found one that was filling the screen. That did solve also the problem of the bands, although it made them smaller and thinner; so I assume what is happening there is that the actual refresh frequency output is not latching to the LCD monitor, or the multiplier for the frequency (from 15KHz to 30KHz), is not exactly accurate, so there are some artifacts that makes those lines in the raster.

I just find out what works, and I won't touch it basically I wish there was a better way to figure out what is going on but as is now; there is not, so at least I am happy that my 19 inches LCD can show the Amiga WB at higher resolution, and also show the standard PAL resolution output, by filling the screen.
Hope this may help other poor souls that like me, have no clue about how the indivision software works

[Jope]

The bands are scaling artifacts added by your monitor. It depends a lot on how close your output resolution and the monitor's native resolution are to each other. If you choose an output resolution that is the same or an integer division of your native resolution, you don't get banding. Anything fractional will result in some kind of banding, especially on lower resolution monitors. WQHD is already pretty nice, you don't see the banding that badly.

It's rather difficult to get a setup that always fills your screen with an Amiga, as the Amiga's video signal resolution is larger than what the graphics usually take up. If you do not want to configure your Indivision to show the Amiga's full output resolution, it is probably the next best thing to boot without startup-sequence and configure it so, that the maximized initial CLI is fully visible.

Basically two compromises:

1) Show everything the Amiga outputs. Games will never fill the screen, but you will never have anything clipped away and you can have the largest possible Workbench screen.
2) Crop to the initial CLI. Games will still hardly ever fill the screen (at least with PAL Amigas), sometimes they will go over the edge of your viewport if the author configured their image position a bit differently to the standard system-configuration.

I always choose 1) because I love my max overscan workbench + I don't want any graphics clipped ever. This was how I had my CRT set up as a kid anyway. To me the Amiga just isn't a machine where games fill the screen due to how the hardware is.

[guybrush]

Originally Posted by Jope

The bands are scaling artifacts added by your monitor. It depends a lot on how close your output resolution and the monitor's native resolution are to each other. If you choose an output resolution that is the same or an integer division of your native resolution, you don't get banding. Anything fractional will result in some kind of banding, especially on lower resolution monitors. WQHD is already pretty nice, you don't see the banding that badly.

It's rather difficult to get a setup that always fills your screen with an Amiga, as the Amiga's video signal resolution is larger than what the graphics usually take up. If you do not want to configure your Indivision to show the Amiga's full output resolution, it is probably the next best thing to boot without startup-sequence and configure it so, that the maximized initial CLI is fully visible.

Basically two compromises:

1) Show everything the Amiga outputs. Games will never fill the screen, but you will never have anything clipped away and you can have the largest possible Workbench screen.
2) Crop to the initial CLI. Games will still hardly ever fill the screen (at least with PAL Amigas), sometimes they will go over the edge of your viewport if the author configured their image position a bit differently to the standard system-configuration.

I always choose 1) because I love my max overscan workbench + I don't want any graphics clipped ever. This was how I had my CRT set up as a kid anyway. To me the Amiga just isn't a machine where games fill the screen due to how the hardware is.

Excellent, thanks for clarifying! I found that my LCD monitor has some settings to change the refresh, so playing with those settings, I was "moving" those bands. They are not gone for good but it looks much better!


For some reasons, the Indivision software does not allow me to set both Workbench video mode and Amiga mode to 1280x1024 (native LCD resolution), so I just use native resolution for workbench, and 640x480 for games, which seems a good compromise between bands on screen, borders and pixellated graphics

[Jope]

Yeps, it's a world of compromises. Really the only good display is a high quality CRT, but that's not so easy either in 2020. :-)

[guybrush]

I wish I had space and was able to find an original 1080s

[jPV]

I'm not sure if we're talking about the same vertical bands/lines, but you get those if you're using VGA output, but also have DVI enabled. So whenever you use VGA output, don't use the "VGA & DVI" output, but just "VGA".