2D Drawing on a 3D Object

How can I draw on the surface of one side of a cube, preferably freehand? I want to do a 2D cartoon mouth on an animated 3D character, sort of like you see on the South Park characters.

You can do it several ways. I’d recommend investigating each and choosing what you find best.

  1. The grease Pencil: The grease pencil is quickly becoming an amazing bridge between 3D and 2D animation within blender. You can animate grease pencil strokes just like anything else.

  2. Animated curves: For something like a mouth you could simply create a bezier curve and add shape keys for the different mouth shapes. Then you can reuse the animated shapekeys over and over.

  3. Texture Painting: You could paint a mouth directly on the texture of your cube in texture painting mode. But if you want the mouth to be animated, this isn’t a good idea, you’d have to do a lot of redrawing and work with image sequenced textures.

Hope that gives you a starting point!

I think the grease pencil is what I want to use, if possible. I want a crayon or jiffy marker look to the mouth. I’m just not familiar with this tool yet.

  1. Animated curves: For something like a mouth you could simply create a bezier curve and add shape keys for the different mouth shapes. Then you can reuse the animated shapekeys over and over.

I tried messing around with 2D curves, but I’m very new to modelling and I was having a hard time getting anything that looked anything like a mouth. My knowledge of what tools are available and how to use them is still lacking.

  1. Texture Painting: You could paint a mouth directly on the texture of your cube in texture painting mode. But if you want the mouth to be animated, this isn’t a good idea, you’d have to do a lot of redrawing and work with image sequenced textures.

This sounds like what you had to do in PovRay years ago to draw on 3D surfaces. I thought there might be a better way by now. I’ll try the grease pen first.

Hope that gives you a starting point!

Yes, this helps a lot. Thanks!

You can create a texture atlas for the mouth, eyes etc then switch the animation states to make specific use of the atlas cycle, another method is by having the eyes, mouth textures on a parented shaped plane to the face to get the cutout animation effect. Try out this file, the creator did a nice job of showcasing anime styled facial animation.

I would go with textures for sure.

@DerpGoose… I couldn’t find what you were referring to at that link. It just took me to the main page.

@Cyaoeu… That looks like something along the lines I want. I’ll check it out.

I want to be able to animate the mouth, rather than just plant different still expressions on the surface of an object and then switch them when needed. I’ve been playing around with shape keys, and they’ll do the job quite well if I can just get a cartoony looking mouth designed that I like. Shape keys offer a lot of variability in controlling the movements. The Blender docs don’t say much about them (they even question why they’re there!), but I found an excellent tutorial by Darrin Lile that explained them very well.