I have GOG version of Martian Dreams and Savage Empire. Naturally, those GOG games come with their own DOSBOX. However, GOG DOSBOX seems to be unable to scale up the game to full screen resolution when using OpenGL, as shown below.

GOG DOSBOX cannot scale Martian Dreams to full screen resolution when using OpenGL.

Out of curiosity, I ran the GOG Martian Dreams using official DOSBOX, and it has no problem scaling up the game to full screen using OpenGL.

Official DOSBOX has no problem scaling up Martian Dreams to full screen using OpenGL.

It should be noted that I captured those screens using plain PrintScreen button in Windows 7 64 bit; I didn't use FRAPS or other, more sophisticated screen capture utilities. And while the captured Martian Dreams main menu is grayscale, the game itself runs in proper colors in official DOSBOX.

In any case, I use the same graphics settings for both GOG DOSBOX and official DOSBOX:

1fullscreen=false
2fulldouble=false
3fullresolution=1360x768
4windowresolution=original
5output=opengl
6autolock=true
7sensitivity=100
8waitonerror=true
9priority=higher,normal
10mapperfile=mapper-0.74.map
11usescancodes=true
12
13language=
14machine=svga_et4000
15captures=capture
16memsize=16
17
18frameskip=0
19aspect=true
20scaler=advinterp2x

I'm not complaining, though. Yes, GOG DOSBOX does not scale up Martian Dreams properly using OpenGL, but I can easily run the GOG Martian Dreams on official DOSBOX. I'm just curious why GOG DOSBOX cannot scale up the game properly, and we might gain new, useful knowledge from discussing this. Both DOSBOXes are version 0.74, by the way.