Try forcing it in your video driver as you would for any other game (that doesn't have an in game option).

Then try running with direct3d / opengl as the output (if overlay has is unaffected - if overlay works after the change then leave it).

Hi. Tried this with opengl, and it didn't work. I read here somewhere that vsync is difficult with dosbox. Maybe it isn't possible?
Thanks! 😀

You have to understand how dosbox emulation works. Dosbox emulates a full graphics card which, instead of the monitor, draws to a portion of memory. This memory is then read and drawn to the screen. OGL/D3D vsync only works for the second part, if the image drawn by the emulated card already has tearing, then it will also show on the screen...

Thanks, didn't think of it that way before. 😀 So, you're saying that visual vsync isn't possible? I'm not a computer expert, so I can't read between the lines here.. 😀 If there is a way to avoid this tearing, it would be great if you could point me in the right direction.
Thanks!

gulikoza wrote:

You have to understand how dosbox emulation works. Dosbox emulates a full graphics card which, instead of the monitor, draws to a portion of memory. This memory is then read and drawn to the screen. OGL/D3D vsync only works for the second part, if the image drawn by the emulated card already has tearing, then it will also show on the screen...

It is possible. In fact there's a patch somewhere on the forum, I haven't checked it out in a long time but IIRC it requires having to manually synchronize the guest with the host.

That only works if the game respects the emulated vsync. If not, there is still gonna be tearing and there's no way to force dos games to use vsync.

Dunno if this would help or not
NOLFBLIM (updated NOLFB) - Enables VSYNC for DOS Games

Maybe try with my experimental VGA patch an play with the ibmtiming option...
VIDEO - Experimental VGA patch (vgaonly commited)
Win32 build only though

I've read that particualr thread, and downloaded the patch. However, the documentation was sparse, and unfortunately I don't have the knowledge to piece together how this works myself (I use a CRT screen). I have some basic knowledge of things, but it ends there.. 😀 I've tried to search for dark forces+vsync on google unsuccessfully, to find out if the game itselfs supports vsync. I only remember when I played it before, I didn't notice that tearing..however I was younger and (maybe) not so critical of the graphics.

Anyway, thanks for all the comments and replies! It's great to play Dark Forces again, love that 4. level up in the mountains. 😀 This game had some pretty darn amazing moments at it's time.
Thanks again!

DosFreak said:

It is possible. In fact there's a patch somewhere on the forum, I haven't checked it out in a long time but IIRC it requires having to manually synchronize the guest with the host.

Here's a link to that patch-
Vertical retrace sync patch

I was sort of laughing to myself as I added the manual calibration. I couldn't find a way to reliably read the retrace status in a cross-platform way.. then momentarily considered using a webcam or something unusual.. and then decided that the combination of the users' eyes plus keyboard is cross-platform (you likely have a keyboard.. and if you care about vsync, you've got eyes). I apologize for that, as it is rather silly.

The patch got applied to at least one unofficial build, but it wasn't fully functional because it requires two keys (to tweak period and offset) to be made available, but this apparently wasn't done for that build. (I think I made a bad typo in one of my posts and said F8 twice instead of F9 or something..). Anyway, if you want to apply this patch yourself, I wish you luck 😀. I've been meaning to come back to it at some point and do a proper patch that automatically syncs perfectly on Windows.. and then in theory someone who is more familiar with other platforms would take a liking to it after playing a silky smooth game of pinball or two, and find a way to make it crossplatform. I should have done that in the first place.

Here's another thread in which I talked about the issues a bit as I was beginning to implement it (could potentially waste a bit of your time reading it, as there is a lot of text):
Screen tearing in DOS games running through DOSBox

As for Dark Forces in particular.. I remember someone mentioning that the game Tie Fighter always had a lot of shearing and there's nothing you can do about it. I believe both Dark Forces and Tie Fighter were developed by Lucasarts, so I wonder if the developers of both shared similar ideas about screen updates (perhaps Dark Forces is another game that shears, with nothing you can do about it).