Determining the optimum size of a sculpt map in Blender

When you start out and create a sculpt mesh - how do you determine the number of faces in the x and y direction to start with?

I will not speculate and wait for an answer on this ..

Related to this, how do you resize the actual sculpt UV map after you baked the mesh to a UV Map.


Oh and how come there is not a simple cube as a default shape to pick from?


Thanks in advance

I would like to make a bookshelf but do not exactly know where to start when picking the size or shape... ( just a random example)

I assume you are talking about primstar ... So this is the description for primstar...


You have 3 values:

x-faces
y-faces
subdivision level

The numbers you choose depends on HOW you want to model. So basically you can work with multires mode, subsurf mode, or just on the vertices (lets name that vertex mode).
subsurf mode and multires mode are directly connected with the number of subdivisions.

So technically:

you choose 0 subdiv levels when you want to work in full vertex mode. Then you would choose 32 x-faces and 32 y-faces (making up a standard sculptmesh). Now this mode gives you the most control over each single vertex position. But you are obliged to handle the caveats of sculptie making by hand... namely LOD. But you could just ignore LOD and head off... The results are not good typically...

You would use 2 levels of subdiv to emulate the SL LOD to some extend. You can equaly choose subsurf or multires mode. Both have advantages and disadvantages. So technically:

The number of x-faces and y-faces corresponds to the LOWEST level of detail. And each level of subdivision corresponds to one additional level of LOD. And that corresponds to a duplication of vertices in both dimensions of the sculptmap (factor of 4 per level). Hence you would typically select 8 x and 8 y faces. then 2 subdivision levels which add a factor of 4*4=16 -> 8x * 8y * 16 = 1024 tada... the standard sculptmap is back.

Now:

subsurf mode gives you the least amount of control over individual vertices. Hence you can not Create arbitrary objects. But as long as whatever you create can be done in subsurf mode the benefit is: You do not need to think about LOD. At least it gets almost automatically done.

Multiresmode is a bit more complicated as you can control the position of the vertices in each level. Unfortunately the vertex positions on one level highly influence the positions on the adjacent levels... So Multires is somewhat hard to work with as long as you are not well used to it and know what you do ...

Now lets look at oblongs: You will use any number of faces of power of 2 in both directions. Other sculptmap sizes are simply not supported fr0m SL. So whatever size you use, it will be internally mapped to power of 2 lengths. It is very hard to give you generic advice about which oblong dimensions would be good for your model. So you will need to check that out by yourself. And beware of spatial resolution issues with oblongs. Often they turn out to have by far less quality than expected.

There is much more to write about this topic. I might have forgotten some important parts. But maybe this is a beginning



- You go to edit mode.
- Then in the UV map you create a new image and set the image sizes to the double of the number of vertices you want to have. i.e. if you had a 32*32 sculptmap, the associated image would be 64*64 pixels. If you wanted to change the sculptmap size to 128*32 then your sculptie will end up with 64*16 faces...


Primstar comes with a set of cubes. e.g.:

add -> mesh -> sculpt mesh
then select one of the Cube shapes

The number of faces and the subdivision levels control how the cube will actually be initially created. Try out some combinations and see how versatile this feature is.


If you want to use the "2 in 1" technique where you rip a sculptie into severeal "unconnected" parts, then a good starting point is the 4*256 sculptmap (8*512 pixels) or the 8*128 sculptmap with 16*256 pixels...

Have fun
Gaia

Thank you - that was a lot of info , and very helpful info at that.

You Rock!