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How to create a custom mesh in Babylon.js?

2019-07-15 09:34发布

问题:

I'm using the babylonjs 3D WebGL library.

It's great library, but I can't find the same, which exists in THREE.JS library.

For example, I have 2D polygons in database, I'm fetching the polygon data from it and then create a custom mesh and extruding it.

With the THREE.JS, there isn't any problem, I can add to some array:

...
points.push( new THREE.Vector2( part.x, -part.y ) );
...
var shape = new THREE.Shape( points );
var extrusion = {
    amount: building.height,
    bevelEnabled: false
};
var geometry = new THREE.ExtrudeGeometry( shape, extrusion );
var mesh = new THREE.Mesh( geometry, new THREE.MeshLambertMaterial({
    ambient: 0xbbbbb,
    color: 0xff0000
});
...
scene.add( mesh );

It's very simple. How to do the same, I couldn't find.

I've found only some information here:

  • http://www.html5gamedevs.com/topic/4530-create-a-mesh-from-a-list-of-vertices-and-faces/

  • http://blogs.msdn.com/b/eternalcoding/archive/2013/06/27/babylon-js-a-complete-javascript-framework-for-building-3d-games-with-html-5-and-webgl.aspx

With such an example (from msdn by Ctrl + F -> You can also create a mesh from a list of vertices and faces):

var plane = new BABYLON.Mesh(name, scene);

 var indices = [];
 var positions = [];
 var normals = [];
 var uvs = [];

 // Vertices
 var halfSize = size / 2.0;
 positions.push(-halfSize, -halfSize, 0);
 normals.push(0, 0, -1.0);
 uvs.push(0.0, 0.0);

 positions.push(halfSize, -halfSize, 0);
 normals.push(0, 0, -1.0);
 uvs.push(1.0, 0.0);

 positions.push(halfSize, halfSize, 0);
 normals.push(0, 0, -1.0);
 uvs.push(1.0, 1.0);

 positions.push(-halfSize, halfSize, 0);
 normals.push(0, 0, -1.0);
 uvs.push(0.0, 1.0);

 // Indices
 indices.push(0);
 indices.push(1);
 indices.push(2);

 indices.push(0);
 indices.push(2);
 indices.push(3);

 plane.setVerticesData(positions, BABYLON.VertexBuffer.PositionKind);
 plane.setVerticesData(normals, BABYLON.VertexBuffer.NormalKind);
 plane.setVerticesData(uvs, BABYLON.VertexBuffer.UVKind);
 plane.setIndices(indices);

 return plane;

But's it's rather not the same as with the THREE.JS. For example I need to count index buffer manually where in THREE.JS I don't need it, also it's a sample with plane only and I didn't find any info about extruding exactly.

So... Maybe, there are some easy ways in BabylonJS?

回答1:

There is no support for extrusion right now but this could be a great feature to add :) I will definitely add it to our roadmap. If you would like to discuss the issue further please ask on the babylon.js forum.

EDIT:

Have ability to create custom shapes now.

http://doc.babylonjs.com/tutorials/parametric_shapes#extrusion