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I'm drastically displacing a mesh (with procedural textures) and due to the displacement being rather big and practically "vertical" there aren't enough polygons and it starts to look very stretched:

enter image description here

Is there a way to get more polygons for these vertical walls? I know that Vector Displacement allows to move polygons in all directions, so I guess I could use the polygons on the bottom of these wholes to "line the walls" but how would I achieve this?

(PS: I'm creating this for Nodevember, that's why it's all on a simple sphere. Obviously, if it was for anything else, I would simply model this shape)

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  • $\begingroup$ It gets quite complicated, and varies case-to-case. You have to 1: Make verticals slope slightly. 2: 'Feed' the verticals from surrounding surfaces, to ensure they have enough topo of their own. 3: Bevel sharp corners. All by procedurally soft-mapping chunks of your original geometry. $\endgroup$ Sep 28 at 8:03
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I don't think this is a polygon problem, you are just stretching the texture so much it just has nothing to put on this side of the brick, it has no information. It's just not possible to do this this way, you have to model it and texture it manually

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  • $\begingroup$ I'd agree with you, but after seeing what some people did for Nodevember I am certain that it is possible to solve this properly... $\endgroup$
    – enyo
    Nov 22 '19 at 12:34
  • $\begingroup$ Well, could you show examples what they did? Maybe this helps to get an idea how they achieved what you want. But I agree it's not a polygon problem. Or course a higher mesh resolution provides better displacement results, but one thing remains: if your displacement for example has a black area next to a white area, and black is 0 m height and white maybe 1 m height, this means the mesh has to go from 0 to 1 in a distance of "nothing", because even with a dense mesh there will be polygons where one is at the bottom and the next at the top - there are none to build the sides. $\endgroup$ Sep 28 at 7:10
  • $\begingroup$ @Gordon interested to know if adaptive subdivision solves this $\endgroup$ Sep 28 at 13:06
  • $\begingroup$ @AllenSimpson I'm not sure how it should. If you have a completely black area adjacent to a completely white area without greys inbetween for example and the displacement is extremely strong, than there will always be a polygon that uses black be close to a polygon that uses white with nothing inbetween. The same goes for adaptive subdivision, only that one black pixel will be close to a white pixel. Maybe there is a grey pixel inbetween if it's exactly on the border of the white and black, but that cannot build something like a vertical wall as if it had real geometry. $\endgroup$ Sep 28 at 13:14
  • $\begingroup$ In my head there's an opportunity for a second pass at generating new geometry once you have the lion's share of displacement applied to the mesh (say subdivide a limited amount and try to form a sort of convex hull first) but I don't know enough about it. $\endgroup$ Sep 28 at 16:02

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