it wouldn't be too hard with a shader, i reckon. backfaces (to the light) treat lighting differently to frontfaces, and the bias of the shadows (i'm assuming they're shadow mapping and not using stencils) would allow the polygons to stay out of their own shadow. if it does use stencils, they'd probably shift the stencil volume prior to projection.

that scene is stunning . of course that's almost entirely thanks to good artwork and good use of LoD (for a screenshot, and i guess on these settings it wouldn't be an in-game problem either). there's no denying that the shaders are definitely good. it's a very good appreciation of real-life visuals -- much of that vegetation (aside from the sub-surf) could look just as good in Doom 3 (tech and hardware), but their (Doom-makers') lack of appreciation of the way light interacts with objects lead to a very plastic appearance anyway.

kudos to the artists and shader programmers. i'd really be keen to see similar screenshots on medium and low settings to compare, coz from the sounds of things it isn't very scalable and perhaps somewhat inconsistent(?).

all in all i think it's the high-res textures and high-poly scenery that's the biggest resource hog.

oh wow... after a second look, i really like the shadows of the mountains cast through the fog. looks good!

julz