Instantiate() Ignores changes to model ?

[Slastraf]

I Instantiate a loaded model like this 
 

worldGenerator->terrainChunk = Model::Load("Models/terrain_Plane.mdl");

...

c->chunkModel = (Model*)terrainChunk->Instance();

then I applied some previously tested code on the surface of the model like this:
 

            Surface* surface = c->chunkModel->GetSurface(0);
            for(int i = 0; i<surface->CountVertices(); i++)
            {
                Vec3 xy = surface->GetVertexPosition(i);
                float height = (rand()%(3));
                if(i==surface->CountVertices()*0.5) {
                    height = -100*(rand()%(3));
                    cout<<"Offset height:"<<height;
                }
                if(i==0)cout<<"height at: "<<height<<endl;
                surface->SetVertexPosition(i, xy+Vec3(0,height*.1,0));
            }
            surface->Update();
            c->chunkModel->UpdateAABB(Entity::LocalAABB | Entity::GlobalAABB);

For every vertex, I set a randomly generated position. This is simplified to show the issue.
All the generated model chunks are the same. A good guess would be that LE copies an already Instantiated model over, and overwrites all changes of the current one to all previous ones, or somehow ignores changes otherwise.
I put a screnshot of the console and two images showing duplicate chunks. There are 9 chunks and each of them looks the same. How to fix this behaviour ?

[Slastraf]

Here another screenshot without the block.
The hole in the middle should only generate 3 times, as the other times the offset for this position is 0. But it is there on every chunk.

[Josh]

Use Copy() if you want to create a new model with unique geometry.

[Slastraf]

9 minutes ago, Josh said:

Use Copy() if you want to create a new model with unique geometry.

I was very happy with performance of Instance. Does Copy have similar performance ?

[Josh]

1 minute ago, Slastraf said:

I was very happy with performance of Instance. Does Copy have similar performance ?

It will be slower under some conditions but you would need a large number of models before you saw much difference.

[Rick]

@Slastraf I would imagine you're recycling 9 chunks? If you make 8 copies of the 1 terrain model then as the player moves around I would think you could just reuse the ones the player is furthest away from so then you only need to call Copy() during initialization of your game right?

[Slastraf]

6 minutes ago, Rick said:

@Slastraf I would imagine you're recycling 9 chunks? If you make 8 copies of the 1 terrain model then as the player moves around I would think you could just reuse the ones the player is furthest away from so then you only need to call Copy() during initialization of your game right?

That would be doable if copy takes a long time. For now the Idea is to copy it and iterate over vertices for every new chunk and hide out of bound ones.

[Slastraf]

Hmmm. I cant tell for sure but copy seems to make it lag even less than Instantiate.