Mesh breaks apart when using vertex displacement with shadergraph.

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Hello, the problem I'm having is that the face's of my meshes are breaking apart when using my little shader. This doesn't seem happen to the sphere.

So... how can I create a mesh that behaves like the sphere and well... stays intact :).

So here is whats happening: alt text

And thats the shader: alt text

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Answer by Bunny83 · Feb 01, 2020 at 06:36 PM

That's not possible unless you base your displacement only on the original vertex position. That's because different faces where you have a UV seem have seperate vertices at the same corner. So the faces are not "connected" in any way. Since you offset your vertices along the vertex normal you will offset the vertices which actually belong to the same position into different directions. So you're moving them apart.

When you have a shared mesh this is not that of an issue since there are (almost) no duplicate vertices. A Sphere doesn't have any issues at the UV seems since the vertices actually have the same normal at the same point. This is not true for most other (hard edge) shapes. Keep in mind that shaders always work on individual vertices (vertex shader) and on individual triangles which are rasterized independently from each other. So a shader can not take other neighboring faces into account. If you want to apply such an effect you either need to provide more information per vertex, or use a different approach. For example instead of using the vertex normal you might want to use the vector from the object origin (in other words the normalized local space coordinate of that vertex). Of course that would only work properly when the origin is somewhat in the center of your mesh.

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zastear · Feb 01, 2020 at 07:22 PM 0

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I think I understand :) Now I just need to figure out how to do that with the object origin. Thank you alot, I feel like I became smarter.

Bunny83 zastear · Feb 02, 2020 at 01:01 AM 0

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I haven't really used Unity's shader graph yet. However ins$$anonymous$$d of your "normal" node you should be able to just use the vertex position and normalize it first. This gives you a direction vector from the object's origin to the vertex.

If you want / need to specify a different center position manually, you have to add a property which you can set from C# to specify the center of your object in local space and just subtract that vector from your vertex position before normalizing it .

Answer 2

Answer by nicholascarrow · Mar 25 at 06:54 AM

you can also try to set your meshes to shade smooth in blender and import them 180 smoothing angle, that might fix it for you

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Mesh breaks apart when using vertex displacement with shadergraph.

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