The data contained in each of a mesh's vertices can be obtained from the vertex buffer. This data includes the position of and normal at the vertex as well as color and/or uv values. You can also obtain the indices for each vertex.
var positions = mesh.getVerticesData(BABYLON.VertexBuffer.PositionKind);
var normals = mesh.getVerticesData(BABYLON.VertexBuffer.NormalKind);
var colors = mesh.getVerticesData(BABYLON.VertexBuffer.ColorKind);
var uvs = mesh.getVerticesData(BABYLON.VertexBuffer.UVKind);
var indices = mesh.getIndices();
Each set of data is an array of numbers as detailed in Creating Custom Meshes.
For example positions will be an array such as [-5, 2, -3, -7, -2, -3, -3, -2, -3, 5, 2, 3, 7, -2, 3, 3, -2, 3] and the
indices array such as [0, 1, 2, 3, 4, 5] giving the following table.
| index | position |
|---|---|
| 0 | (-5, 2, -3) |
| 1 | (-7, -2, -3) |
| 2 | (-3, -2, -3) |
| 3 | (5, 2, 3) |
| 4 | (7, -2, 3) |
| 5 | (3, -2, 3) |
Make sure that the mesh has been set as updatable on creation. Then this is just a matter of altering any of the data in the positions, normals, colors and uvs arrays to suit the project followed updating the vertex data
mesh.updateVerticesData(BABYLON.VertexBuffer.PositionKind, positions);
mesh.updateVerticesData(BABYLON.VertexBuffer.NormalKind, normals);
mesh.updateVerticesData(BABYLON.VertexBuffer.ColorKind, colors);
mesh.updateVerticesData(BABYLON.VertexBuffer.UVKind, uvs);
Note: When creating your own custom mesh to make it updatable you need to add a second parameter with value true when applying the mesh to the vertex data.
vertexData.applyToMesh(customMesh, true);
Playground Example Scaling Positions -
Playground Example Playing Around with Positions -