yes it's just a heightvalue and some math

I made it like this because I have no idea how I could write this as an objectshader

But I'm still having some very little artifacts I'd like to fix.

It looks good but is also very slow on my machine. I wonder if you are clipping pixels if they are not on the water plane and/or not visible? Because if I look against in the middle of the scene along the XY-plane, I get no fps increase (it stays the same).

To turn that into an object shader you would have to render the scene like usual in the camera-view but without the water-plane. And in a second, staged view you would render only the water plane and turn NOSKY on. By this the z-Buffer won'tz be cleared and the plane gets clipped against the z-Buffer of the camera view. With TargetMap you can then access the previous rendering result.

Thanks for the information HeelX.
Yes I am clipping the not-affected pixels and yes the shader is slow but I'm pretty sure that this isn't caused by the watershader because it 'just' uses some clever math, but nothing too complex.

I think it's the complex & inefficient objectshader I'm using there and the textures because they don't have mipmaps.

EDIT: I just tested it, in the worst case the textures and the specular lighting reduce the framerate by 50% (~120 fps)

On my machine which is rather fast, I got only 15 fps!

thats weird...

I know!

First version of my street creator.
You can't edit the street curve but that will be the easier part i think
I will support also rivers carved in terrains.

@Kartoffel: Just tested your pp water demo, surprisingly the water isn't visible at all on my machine/ 5870. I can see the rather nice material on the curtains and the two colored lights but no water.

You need to use the ctrl and shift key to change waterheight.

@MasterQ32
Will u release this wonderfull tool into the wild ?