HOw to change a triangle in a mesh?

General Discussion
1

Hello,

I wanted to change a triangle position inside a mesh (when the player click over the surface), so I tried this (using a collision ray):


Triangle t = results.getCollision(i).getTriangle(null);
Vector3f n = new Vector3f(0, 0, 10);

//n = n.mult(20);

t.set1(n);
t.set2(n);
t.set3(n);

results.getCollision(i).getGeometry().updateModelBound();


I correctly detect the geometry, but I cannot move the triangle. What's wrong? Can you help me please?
Thank you!
2

The triangle is not actually part of the mesh, see the wiki entry on custom meshes about modifying meshes.

3

Hello,

I red that article (https://wiki.jmonkeyengine.org/legacy/doku.php/jme3:advanced:custom_meshes) but it does not explain how to modify it, only the creation

:frowning:



What do you mean with

The triangle is not actually part of the mesh
? How can I modify a face of a mesh? How to modify a vertex?



Thank you for your support!

4

Modify the buffers that the custom meshes tutorial deals with.

5

Understood, thank you!

One question more: based on the fact I will use a ray to check which face I’m working on, how can I find the vertex in the buffer associated to the selected face (using ray and colliders)?



[java]

Triangle t = results.getCollision(i)[/java]



I’m working on the code based on “HelloPicking” in the wiki:

https://wiki.jmonkeyengine.org/legacy/doku.php/jme3:beginner:hello_picking

6

I guess you’ll have to find the vertices that have the same coordinates…

7
nehon said:
I guess you'll have to find the vertices that have the same coordinates...


OMG! I hope this is not the method :'(
I hope there is comething like an index to work with it.
8

Actually you’re right

the returned triangle as an index parameter that is the index of the triangle in the corresponding mesh.



look at the getTrangle method in the Mesh class