A couple of screen resolution questions

[Nodoyuna]

Hi

I have latest GroovyMAME installed, with Calamity's CRT Emudriver on a CRT TV, using Windows 7 at 640x480x30 Desktop resolution
I know it's working because it can change resolutions and all, but now I'm in "fine-tuning" mode
I have some questions:

1) About 640x480: GM changes to 640x480i, with the same refresh rate as the original. I think that's correct and it does look great, but it's an interlaced mode. I've read in another forum that if you force 640x480 games to 640x240 you can get a progressive resolution, but I don't really know how to do it, but it should be related to individual .INI files... Does anybody knows something about this?

2) Most of the games are not centered on screen. I've managed to center GroovyMAME game selector itself, but when I play the games, they're not centered. Any ideas on how to resolve it? I'm using arcade_15 monitor

3) Finally, for now at least... How can I add a new modeline? I've installed 120 modelines with VMMaker, getting them from MAME.exe, and if I try to install more modelines, the old set is replaced with the new one. So, how can I add new modelines, if needed, without losing the ones already installed?

Thanks in advance

[big10p]

What monitor do you have?

Standard 15khz arcade monitors can't do progressive scan for 640x480, only interlaced. Not sure why games display off-centre, although you can centre them in the mame slider controls. I recommend using Super Resolutions instead of trying to create a specific modeline for every game.

[Nodoyuna]

What monitor do you have?

Standard 15khz arcade monitors can't do progressive scan for 640x480, only interlaced. Not sure why games display off-centre, although you can centre them in the mame slider controls. I recommend using Super Resolutions instead of trying to create a specific modeline for every game.

Hi

I have a CRT Television, it does accept 50Hz and 60Hz and it's connected to PC via VGA-SCART cable in RGB mode.
In GroovyMAME and VMMaker, the monitor preset is "arcade_15"
The trick of forcing 640x480 games to 640x240 is about force that resolution and apply bilinear filtering to scale to 480... It's still interlaced, but forcing it to 240 first, the display is clearer because bilinear filtering does not blur the image... It does sound good in theory at least...

I'll try slider controls to center the image... Once centered, it stays centered to that game, or if I close GroovyMAME, the next time I choose the game will be off-center again?

[big10p]

Actually, forget what I said about adjusting screen position in MAME. Just realized it'll cut off the edge of the image, instead of moving the whole thing. I suspect your VGA-SCART adapter is somewhat to blame for the off-centre image. See if you can find how to access your TV's service settings. You may be able to position the screen image with those.

Hmm, not sure how bilinear filtering is going to help things. No filters should be needed with a CRT.

[Recapnation]

The trick of forcing 640x480 games to 640x240 is about force that resolution and apply bilinear filtering to scale to 480... It's still interlaced, but forcing it to 240 first, the display is clearer because bilinear filtering does not blur the image... It does sound good in theory at least...

This is nuts. You can halve the vertical resolution with GM indeed (or force whatever resolution, for that matter, but type unevenstretch 1 in machinename.ini if you're subscaling since integer subscaling is not supported), but what you suggest there goes nowhere. You force a particular resolution in order to display that resolution, not to modify MAME's code in regards to the driver's internal resolution. But anyway, taking off half the graphics can never be a good idea, unless it's originally a game with line-doubled/upscaled visuals.

[Nodoyuna]

The trick of forcing 640x480 games to 640x240 is about force that resolution and apply bilinear filtering to scale to 480... It's still interlaced, but forcing it to 240 first, the display is clearer because bilinear filtering does not blur the image... It does sound good in theory at least...

This is nuts. You can halve the vertical resolution with GM indeed (or force whatever resolution, for that matter, but type unevenstretch 1 in machinename.ini if you're subscaling since integer subscaling is not supported), but what you suggest there goes nowhere. You force a particular resolution in order to display that resolution, not to modify MAME's code in regards to the driver's internal resolution. But anyway, taking off half the graphics can never be a good idea, unless it's originally a game with line-doubled/upscaled visuals.

OK, things are clearer now...

About centering the screen, i've tried slider controls but, is there any more automated way? I've centered the main mame screen by changing some values in the monitor preset... Can this be done in a game-per-game basis?

Thanks

[Recapnation]

What Big said. Use the slider controls only to solve very minor overscan issues, if anything. Gaining access to your TV's service controls first and foremost is mandatory. Once your TV's better accommodated to your system's demands, you can try the steps in F.2 here:

http://geedorah.com/eiusdemmodi/forum/viewtopic.php?pid=987#p987

[Nodoyuna]

So, do I need to go to Arcade OSD and configure the centering, for EVERY game, one by one?

[Recapnation]

You didn't read the whole guide, did you? As Big pointed, with super resolutions you'll have a big part solved, since normally you'll only have to worry about the vertical centering and amplitude. For those games you're not happy with super resolutions for whatever reason, the machinename.ini approach may be necessary, yeah. But it all depends on your tolerance to over/underscan and your will to modify your monitor's own settings much like you had to do with the original hardware, in the end. In the worst-case scenario, games sharing a video mode originally will share the concerning configuration in machinename.ini, and many even are already grouped by drivername.ini if you create it.

Start with super resolutions, get your monitor accommodated to a 224-lines, 60-Hz game since it's the most used overall and try all the more advanced things when you're more confident with how it all works.

[Nodoyuna]

Hi
Thanks for the tips...
I've centered the image with TV's service mode and GM is more centered now by default
One thing I've checked is to disable interlaced modes (interlace = 0) and now everything that's 240p is centered by default
Is OK to have interlaced modes disabled in mame.ini? Games seems to work 100% anyway
Thanks in advance