Hry all, im trying to make a room that is curved, one thats like an oval and one that is like a semi circle.
QUESTIONS:
1) how do i make a round room w/o useing endcap (because i need both sides of the wall to carry a texture)??????
2) how do i clip the floor and cealing so that it perfectly fits w/o going beyond the walls and w/o using "cap selection" (because i can only texture one side of a capped selection)????

NOTE: this room will be visible from inside and outside so i need to be able to have textures on both sides of all surfaces (minus the floor of course)

Easiest way, is to make a textured brush over a quarter of the room, goto the Curve menu and select Bevel, then with the bevel selected, goto Curve > Matrix > Invert (ctrl-I is default hotkey to invert a patch).

Then, you can just clone that curve, and rotate it to fit all the walls.

To get both sides of the wall to be textured, simply use two different patches, with the matrices facing outwards, and space them apart by however thick you want your wall to be.

im not sure bout this but to make textures on both sides i use thicken (ctrl+T)

That works too. It would probably be better to do that if you wanted to add thicness to the curve but I personaly like building it from scratch : /

If you use thicken, don't forget to delete the unnecessary top, bottom and side patches. :) Or don't use seams.

To get proper ceiling and floor, you can form them from a simple patch mesh by editing its vertices (V). Or you can cap the inside bevels with SHIFT+C.