Hello
I am new to bryce. Can anyone point me to tutorials on using the terrains in the boolean palette or can someone please tell me how these are used. I am trying to make the river and the lake ones but do not understand how one does it.
thanx Blue Boy

I can't think of any tutorials for that specifically...
Anyway, the terrain(s), or objects, that is going to 'cut away' should be set to negative ('A' - Attributes). The object(s) that it is going to be 'cut away' from should be set to positive.
Then group ('G') the two.
 - A material on the negative terrain will cover the cut-out part. Use a rocky material, or whatever, for the water bed.
 - Some part of the negative boolean terrain has to be above the postive boolean part, or you can't see it.
 - You can select, move, and apply materials after the boolean. CTRL + mouse click, select from the list that pops up.
Then you need either a plane, a terrain, or an infinite plane' to use as the water. Doesn't have to be booleaned. Has to be somewhat below the 'lip' of the cut out. I usually use terrains for water, with a 'wave' image applied in the terrain editor, to get some waviness for the surface.

Thanxs guys working on it

My major advice for making water features is to ignore them.  I used to try and "build the water" so I had a complete surface underneath, then realized I was going about it wrong.  So I set my infinite plane to the water I wanted, and then focused on building the shores and let the water do what it wanted.

Over time I then learned to build waves and currents with terrains, customize textures, blending different opacities and reflections, and mixing terrain waves and wakes with planes, slowly adding more and more to my lexicon of tricks.

So, I never worry about the shape of the river, I worry about the shape of the shore, and customize individual pieces to do what I need them to, to gain the result I'm looking for.