So, recently, I was playing Return of Castle Wolfenstein, and a detail caught my attention – clouds in the sky. This game uses a trick with flat planes in the skybox to give the animation of moving clouds in the sky. Honestly, I find this effect very appealing, so I decided to use it in my map Ice Tower. I don't know why more mappers don't use this trick, considering it's easy to implement and not expensive to render.

This texture is based on one that already exists in the game (specifically in Half-Life 2), called 'cloud001c.vmt.' I modified it to suit my needs.

In this download, you'll find the texture (VMT and VTF) and a vmf demo so you can see how to implement it in the 3D skybox.

Just put the 'material' folder into the 'tf' folder of your game.

I also included the original texture 'cloud001c.vmt' renamed to 'scroll_clouds_1.vtf' in case some versions of the source engine don't have the original texture. You can use outside of Team Fortress 2 if you want.

If you want to adjust the brightness of the texture, just edit the $color value in the VMT. Higher values make the clouds brighter, while lower values make them less bright. If you want to modify the speed at which the clouds move, just edit the $rate value. Higher values increase the speed, while lower values decrease the speed:​

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