NPR outline

solar

What's the best way to generate a comic book style outline for a character? At the moment I've tried using a cloned mesh with a push modifier with inverted faces and a black material. This works really well except in areas like lips and eyes. I've also tried using the toon shader in ShaderFX but the outline seems more blocky and doesn't quite follow the outside of my mesh as well as the push modifier method. Are there other better ways of doing this?

rooster

what program, and are you talking realtime for games or just rendering

Ben Cloward

I've used the clone mesh method and the shader method. For the problems you describe with the cloned mesh method, you can simply delete the faces in the outline mesh where you don't want them to be (delete the faces around the eyes and mouth, etc.)

With the clone mesh method, you can create colored outlines by texturing the cloned mesh with the texture that contains darker colors than the regions that the outlines surround. For example, if you model is red, you could apply a dark red texture to the inverted faces. This method works pretty nicely - but it really depends on the style of toon shader you want.

For the shader method, there are lots of adjustments you can make to the shader. I think the reason the edge is blocky is because it's using an "if" statement in the shader. You can change the shader to use a lerp (linear interpolation) instead. This will make the edge softer. At that point it basically becomes a fresnel term and you just have to push it out to the edge with a scale and bias (multiply the result by a tweekable constant and then add a tweekable constant).