Extrude CAP problem

[c75]

"CAP" procedure of extruding works not so good

Here is the demo of problem

http://www.babylonjs-playground.com/#EALGM#0

 

Problem in Polygon triangulation algoritm. Will be nice if babylon include some effective triangulation algoritms.

I think it can be good base https://github.com/mapbox/earcut for it. Unfortunately I'm weak to realize it myself

[jerome]

yep

 

The extrude cap process only computes the barycenter of the shape, so it can get some weird results if the shape isn't concave nor symetric what is the case in your  demo.

This a (my) choice of implementation because the extruded shapes can be dynamically morphed and the computation speed really matters to change the geometry on air. In brief, the cap algo must be as simple as possible.

demo : http://www.babylonjs-playground.com/#20IBWW#2

doc : http://doc.babylonjs.com/tutorials/How_to_dynamically_morph_a_mesh#extruded-shape 

 

So if you have a convex model shape and you don't need to morph your extrusion dynamically, I would suggest you not to use the embbeded caps but to generate a triangulated plane polygon instead : http://doc.babylonjs.com/classes/2.2/PolygonMeshBuilder

 

 

Unless someone wants to try to implement a fast cap triangulation process 

[c75]

Jerome, thank you. Now I understood why it realized so. And i did not know about "PolygonMeshBuilder" It works fine in my case.

http://www.babylonjs-playground.com/#EALGM#1

[jerome]

happy it helped you