i was playing a custom map (cant remember what it was called) and saw textures that changed sort of like an animated gif.

does anyone know how to create these?

The only way you could do it in COD4 is to make a series of textures and texture a few script_brushmodels with each frame. Then you could show/hide each frame as required (max speed would be 20fps).

Alternatively, you could create a looping fx which spawns flat particles with those textures and animates, with no frame speed limitation.

thanks. i should be able to do that :D. never thought of it like that

So, you can add custom textures to the efx ? How ?