Texture access

..how to access texture applied in to some objects, in order to make that texture moving , for example, waterfall or something? I dont want to load that texture and apply again on to same object(I assume its memory waste)...

getsurfacebrush? or some of the surface commands may help.

i thought it would be handy when you make a brush and apply it to entities, that any changes you make to the brush would effect any surfaces it was used on.

shoots me in the head for wanting that

Yeah. You need to use GetSurface(), then GetSurfaceBrush(), then GetBrushTexture(). I think that's the right order anyway :D. Mind you will be creating a new brush so you'll need to free it.