I have the same problem. The only way I can see the map is to turn of "Enhanced Water Effects" and "Landscape Bumpmapping" off in the graphics settings to see the map then turn them back on after.
Edit: I made a ticket on January 31st but have not yet received a reply yet. Im using Windows 7.

Probably won't help, but just in case - forcing anti-aliasing through the drivers (and disable in-game if it's enabled) - this worked on one or two other games for me.

Tried Giants Hook. It at least made it so the fog of war lifted when i walked around, but I still get the giant diagonal light and the map is broken, unless I turn off Enhanced Water Effects. I sent in a ticket, it seems to have just faded away.

Same problem here with ATI HD 5850.

Also have the retail version (I think it came with one of my old nvidia cards) where I don't remember having this issue.


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Ended up installing the 1.497 (1.5 Beta) patch. With this the map semi-works (still weird lighting but it's usable) but the graphics glitch with landscape bump mapping on so that had to be turned off either way.

Sigh, it's an old game, always had issues even when it was new - but it's still great, if you can get used to the weird genre mix, and to the even weirder humour

Same problem here, just got the game, everyone here seems to having the problem since 2008 so I don't have much faith in them releasing a fix.

The patch linked above isn't accessible any-more, does anyone know of any other workaround to this annoying issue?

EDIT: FOUND A PATCH: http://www.giantswd.org/?file=60

FIXES BOTH THIS PROBLEM AND ANOTHER PROBLEM INVOLVING VSYNC/MOUSE SENSITIVITY. I RECOMMEND IT.