I figured out a way to make getting the right color of cullfog much easier. Normally, you have to guess to get that nice looking fog that fades away into the background. Open up the env folder and find your sky's tga files. Pick either lt, rt, bk, or ft. Open it in Adobe Photoshop, or some image editing program. you need to find the rgb values of the horizon. In photoshop, simply move your mouse over the horizon and the rgb values show up in the info area (on my version at least). You may have to find another way to do this if you don't have that feature. Take the three numbers and divide them by 255. The results are the three rgb values you use for cullfog. You may need to add or subtract a little from it to get it perfect, but it is very close.

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