Sculpties - Blender - UV map question

Hi, I'm a bit of a newbie at this, so please bear with me. I've been doing all the tutorials on making sculpties with Blender, and I think I have the basics down. My problem is that I want to make some shapes that are (for me) difficult create by starting with a sphere.

I'm trying to model a chair seat that is about 1cm thick, and curved in 3 dimensions. (something like this ->http://www.dwr.com/productdetail.cfm?id=11708) I think I can model the shape by using other methods, like manipulating a grid or plane and extruding it, or using bezier curves. But it seems like those shapes do not unwrap to a rectangular grid, and this is where I don't know what I'm doing.

Is is possible to somehow "force" those shapes to unwrap to a grid? I'm willing to do some research to figure this out, but I thought I'd ask first so I don't waste my time. Or, if anyone can point me to some info on how to get a shape like the one I want from a sphere, that would be appreciated too.

Short answer: no. You can't force the unwrapping to be rectangular. However, you shouldn't have to unwrap the UV at all. The UV map will have the same topology as your sculpt map. You can use a larger or even an oblong texture, but it'll be mapped according to your sculpt image.

Hi! I don't claim to be very professional at sculpties in blender (as a matter of fact..im still trying to figure out how To accurately paint the sculpties without having to eyeball it with a grid in SL) but the following tutorial should help. It works with NURBS, and the term "Unwrap" isnt used once. Instead, it has modded in a few ways that have ALWAYS worked for me.

http://iramblesorry.blogspot.com/2007/05/how-i-learned-to-stop-worrying-and-love_28.html

It's a lot easier to get the square UV map first by following the tutorials then use that base sphere to make sculpties from. There's no one click solution to get a square UV map from a mesh modelled another way, you'd basically have to select the points on the UV map and align them by hand.

As far as tips on modelling, using b key to box select then s key and x y or z to constrain to an axis, then 0 key on numeric keypad and Enter will scale the selection to a flat plane. You should be able to rough out a box shape for the seat with those. Using proportional edit (toggle on/off with o key) is a good way for working on curved shapes. You can set the range of influence with the mouse wheel.

Using edge or face select modes (in edit mode the select modes are the 4 dots, double lines, triangle and box icons) and the shift key to select multiples will let you move a section of the mesh quicker than working vertex by vertex.

Using alt right click to select a loop is another handy shortcut

ctrl + to grow the selection and ctrl - to shrink it is another useful thing to know.

the "To Sphere" tool is also handy, this works based on the cursor position so for example, you could left click about 8 times the size of the mesh behind the seat, select the front of the seat vertices and use "To Sphere" to get a rounded front.

Thanks for all your replies! I'm looking forward to trying them out.

Don't worry about using a sphere, it is not a requirement that you use a sphere as a starting
object in blender.

I would recommend using a cylynder as it is easy to prep it into a nice flat uv map
Before you begin modeling it.

You can also use the Amanda Levitski method from this tutorial-
http://amandalevitsky.googlepages.com/sculptedprims


I often recommend that one as it is the one I learned on.

There is a link at the bottom of it to the blend file which has the rgb bake settings already done as well as the uv prep.
Just make sure that the uv map covers the whole UV grid Before you begin modeling.
When done in this way the changes you make to your model are reflected in your uv map.

I've had a similar problem with trying to sculpt a basic rounded square (for mattresses, sofa seats etc) and I'm finding it so difficult! Whatever I try, will almost never produce an even rectangular UV-map. Does anybody have any quick or basic advice on how you would start and proceed to sculpt and import to SL a rounded square?
Thank you so much in before hand.

Milla, I'm using Tokoroten for 'rounded' Squares. I then resave them as a png from .tga and load it into SculptyPaint8 for fine tuning.

Tokoroten uses Lathe process. unlike most 3D modelers you make your shape essentially from top view at your given points and reshape by hand. This can take practice, I've owned Photo Impact for years which handles path editing (like drawing point by point, instead of pixel by pixel) similar to this so it was no problem for me to wrap my head around the concept of Toko.