From hi-poly sculpted model to low-poly animated (?) model

Hi everyone,
I am modelling a character to make animations.
I have sculpted a head, and I am happy with it, but it is very high poly mesh, and it would be hard to animate.
So I am doing an other head paying attention to topology.
Are there specific tools to do that ? An easy way to “draw” loops on the sculpted mesh and turn them into a mesh ?
Any hints, tutorials of pieces of advices mostly welcome.



Here you see I’ve drawn the loops in 2D on XZ plan (on the left) and I’d like to project those on Y axis (on the right).

Take a look at this video http://www.blendernerd.com/retopo/the cool thing about this method (for me) is you can go with a really low poly mesh that is only focused on the topology and still end up with a not so low poly mesh that works really well.

Great ! this is exactly what I need ! I don’t understand how I missed it in the first place.
Just a question : Do you keep the high poly mesh and the modifier of do you apply the modifier and store the high poly in another .blend file ?

It sort of depends on what you’re planning to do with it. Your sculpt there doesn’t look very detailed; it doesn’t have a bunch of wrinkles or pores or other fine details. That tells me that you’re using the sculpted model to organically feel out a shape for your model, not to create the fine high-res details that you would want if, for instance, you wanted to make extremely realistic skin.

If my impression is correct, you won’t need the high poly model at all once the low poly version is done. It’s essentially a memory-intensive reference sketch, and contributes nothing to the final model (phrasing it that way kind of makes it sound like a criticism of the technique, but it’s not. I do the same thing). So when you’re done with retopo, I’d recommend saving a duplicate of your blend file with a new name (just for oh-crap-I-broke-it-backup purposes), then just delete the high poly version.

Alternatively, if you are planning on using the high poly to sculpt in those fine details later on, you’ll need to keep it around long enough to bake a normals map out of it. But even then you won’t need to keep it beyond that step. In any case, by the time you’re ready to animate, you won’t need to have that high poly model anymore, though as you can see the reasons for this can vary.

Thanks for the explanations. You’re right, my model is for a cartoon like animation. no need for any details.

With that low level of detail, sculpting isn’t really a necessary step at all. The only reason to sculpt for something that simple is if you’re using the sculpt as your reference sketch, essentially doodling in 3d rather than drawing a character sketch and using it as a reference image while modeling. Nine times out of ten, I’d say just use a reference image. Sculpting for something this simple just takes up too much time with too little benefit. Of course, since you’ve already done the sculpt, I guess that makes this time number ten. :yes: