1
$\begingroup$

Does anyone know of a good resource to learn how to create a low poly version of my character, create normal maps, and apply them to the low poly mesh?

I'm specifically confused about whether I should be making shapekeys for the high-poly mesh for facial expressions before creating a normal map. Would I just need to make one normal map and that would cover all the shapekeys? Or would I need to create a normal map for each face shape?

I also have yet to successfully transfer a normal map despite following some YouTube tutorials, so I want to make sure I get this right.

Thanks.

$\endgroup$
1
$\begingroup$

First of all, is your character using a Mirror Modifier to generate symmetry? If it is, you should apply it first before doing your UV mapping, texturing, rigging, and shape-keying. (Symmetrical UV maps are OK in some special cases, but definitely avoid them if you will need to use a Normal Map.)

As for creating a low-poly mesh from your high-poly one, check this technique out. It might seem a bit confusing if you're just starting out, but understanding it can save you a lot of time when creating your low-poly meshes.

Your Normal Map will not change with the Shape Keys, nor should it need to unless you're trying to do something overly complex.

Use the high-poly mesh to bake your maps onto the low-poly mesh. Keep both handy, and only delete your high-poly sculpt once you're done baking textures. Keep a version of your project saved that still contains your final sculpt in case you need to re-bake later.

$\endgroup$
  • $\begingroup$ Thanks for the detailed guidelines and linking me to that awesome shrinkwrapping post! I'll definitely check it out! I was about to start using reoptoflow, but this method looks like a huge help. I'm not using a mirror modifier. The character is slightly asymmetric. I generated it using makehuman. So I suppose that's a good thing based on your answer. One followup question: If I need one normal map, do you know if there is a way to bake it from a specific shape key I've made on my high-poly mesh? My basis key doesn't have the facial wrinkles I want. Thanks! $\endgroup$ – Tyler Feb 17 '17 at 3:37
  • 1
    $\begingroup$ When you bake a normal map Blender ignores Shape Keys. There is a way to get around this though. It's a destructive edit, so save your project first. You can move your key above the "Basis" key in the stack, then delete "Basis". This then becomes your mesh's only shape, and therefore you can bake it! Do not save your file after doing this or you'll be stuck with that deformation. Note that if you have multiple Shape Keys creating the facial expression you'll first need to combine them using "New Shape From Mix" - this option can be found by clicking the triangle button below the +/- buttons. $\endgroup$ – Mentalist Feb 19 '17 at 8:32
  • 1
    $\begingroup$ I should clarify: When you bake a normal map Blender ignores Shape Keys IF you are doing Bake From Multires (baking using one mesh). It does take Shape Keys into account if you are doing Selected to Active (baking from one mesh to another). That is to say, the deformations of your hi-poly mesh's keys will have an effect on your lo-poly mesh's baked texture. And it works the other way around too, if you have Shape Key deformations on your lo-poly mesh. $\endgroup$ – Mentalist Feb 19 '17 at 8:51
  • $\begingroup$ This was extremely helpful! Thank you, I was able to get everything baked exactly how I needed! $\endgroup$ – Tyler Feb 22 '17 at 21:50
  • $\begingroup$ Great! I'm glad to hear it helped. $\endgroup$ – Mentalist Feb 23 '17 at 0:40

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.