I have a tooth model. I want it to be white outside and (any) voronoi texture inside. Is it possible?

tooth model

tooth model with materials

How to ger rid of those red things? They're caused by boolean modifier

  • $\begingroup$ how are we supposed to see the inside of your tooth, is it with a boolean? $\endgroup$ – moonboots Aug 26 '19 at 10:17
  • $\begingroup$ @moonboots yessss $\endgroup$ – cxnt1 Aug 26 '19 at 10:21
  • $\begingroup$ you've used image textures but didn't pack them, so the objects are pink, please reupload versions with packed images $\endgroup$ – moonboots Aug 26 '19 at 11:51
  • $\begingroup$ How do I pack images in blender? $\endgroup$ – cxnt1 Aug 26 '19 at 11:52
  • $\begingroup$ top horizontal menu on the left, File > External Data > Pack All Into Blend $\endgroup$ – moonboots Aug 26 '19 at 12:03

So, as your question is equivocal, you have 2 possible situations: Either you're talking about an object that is open and you need to give 2 different materials to each side of the same face OR you're talking about the intersection of an object with its boolean object.

  • Option 1: For an open mesh, use the Geometry > Backfacing node as you explain. Mix it in a Mix shader to separate 2 different shaders.

enter image description here

  • Option 2, if you're talking about the face that is the intersection between your tooth and the object you'll use as boolean, you need to give your boolean object the material you want to see, and make sure that your tooth has both its natural material + the same material as its boolean object. Here, both the cube and the tooth have the orange material:

enter image description here

  • $\begingroup$ Backfacing solved my question $\endgroup$ – cxnt1 Aug 26 '19 at 10:29
  • $\begingroup$ oh you're talking about the inner face AFTER applying the boolean? $\endgroup$ – moonboots Aug 26 '19 at 10:34
  • $\begingroup$ does it matter if you apply boolean before or after? @moonboots $\endgroup$ – cxnt1 Aug 26 '19 at 10:37
  • $\begingroup$ if you apply the boolean, my method won't work, what you were asking for was for an open mesh I guess? $\endgroup$ – moonboots Aug 26 '19 at 10:39
  • $\begingroup$ What is open mesh? $\endgroup$ – cxnt1 Aug 26 '19 at 10:40

Geometry node in shader editor solved my problem (Texturing inside of model black)

enter image description here

  • $\begingroup$ Keep in mind that the normals face the opposite direction on the backfaces, so if you mixed shaders that have IOR for example(like the very popular Diffuse and Glossy mix controlled by Freshnel node), you would need to invert the IOR value(1/IOR) to get correct results. $\endgroup$ – Martynas Žiemys Aug 26 '19 at 12:05
  • $\begingroup$ How can I do that? @MartinZ $\endgroup$ – cxnt1 Aug 26 '19 at 12:06
  • $\begingroup$ Like I said, just divide 1 by the IOR value you would normally enter for the part of the shader that is for the backfaces. So say you are making a plastic with Diffuse mixed with Glossy and controlled with Fresnel node and you enter 1.3 as the IOR, let's say you now wish to use the same mix for the backfaces and plug the result of it into your node setup to the bottom input of your mix node. The material will now look wrong. To fix it you need to change the IOR value to 1 divided by it. Like this $\endgroup$ – Martynas Žiemys Aug 26 '19 at 12:31
  • $\begingroup$ Please feel free to edit this into your answer if you find it useful or think this might be useful for whoever stumbles upon it in the future. $\endgroup$ – Martynas Žiemys Aug 26 '19 at 12:33
  • $\begingroup$ @MartinZ It didnt help $\endgroup$ – cxnt1 Aug 26 '19 at 12:41

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.