Modify vertex-positions of Plane?

Hello, I’m new to Three.js and started playing around with the demos. I’ve tried to modify the positions of my plane like this:

var oGeo = new THREE.PlaneGeometry( 1, 1, 1, 1 );

oGeo.vertices[0].position.z =  -0.5;
oGeo.vertices[0].position.y =  0.2;

That worked for the positioning, but I think my light won’t get applied on this plane like it should. There has to be a proper way doing this. Can you help me, please?

What I’m actually trying to do is a tilemap with 16x16 planes. I want to be able to modify the y-position of every plane dynamically.

[matthoz]

I’ve added those two lines:

this.oGeo.computeVertexNormals();
this.oGeo.computeFaceNormals();
//...(old)
this.oGeo.__dirtyVertices = true;
this.oGeo.__dirtyNormals = true;

Now the light seems to be correct. Now I can realize my real-time-modification of those planes. But it really is a very dirty solution, isn’t it? Is this the only way to realize real-time modification of Objects? I know that it is possible to do this directly on the shader, but for the start, this is to high for me. Any other hints?

Btw. Thank you very much fabricasapiens

[chyde]

@murci thank you SO much for the heads up about verticesNeedUpdate