Create a new mesh with a polygon points list (Triangulation)

[JKoehoorn]

I added extrusion to your code. it's a optional parameter and works with holes to.

see https://github.com/BabylonJS/Babylon.js/pull/522

 

[MauJovi]

So, how is it going? I want to create polygons by points and extrude them. What's the syntax? I only found the example with the big string... Is there a way like: Mesh.addPoint, so I can do simple loop to create it... Thanks

[JKoehoorn]

var contour = BABYLON.Polygon.Parse(PointsData);
contour.push(point)
var b = new BABYLON.PolygonMeshBuilder(name, contour, scene);

 

You could push points into the contour and then create tour polygon.

Job

[MauJovi]

5 hours ago, JKoehoorn said:

var contour = BABYLON.Polygon.Parse(PointsData);
contour.push(point)
var b = new BABYLON.PolygonMeshBuilder(name, contour, scene);

 

You could push points into the contour and then create tour polygon.

Job

What I couldn't understand before was that backslash in the string, but i realized its function was to concatenate. lol. Didn't find it good, cause it makes to lose the indenting.

Anyway, thank you.

[MauJovi]

By the way, i was talking about this example http://www.babylonjs.com/Demos/Polygon/polygon.js

[MauJovi]

I'm getting the "e.equalsWithEpsilon is not a function" error.

My code:

    var contour = BABYLON.Polygon.Parse('');
    for(var i in this.arrEstandes2)
    {
        this.arrEstandes2[i]['pontos'] = jQuery.parseJSON(this.arrEstandes2[i]['pontos']);
        for(var j in this.arrEstandes2[i]['pontos'])
        {
            contour.push(this.arrEstandes2[i]['pontos'][j].replace(',', ' '));
        }
        break;
    }
    var poly = new BABYLON.PolygonMeshBuilder('polygon', contour, this.scene);
    poly.build();
    poly.material = new BABYLON.StandardMaterial("mat", scene);

Am I not including something? Babylon and poly2tri are on...

Thanks

[Dad72]

poly2tri is an external file and is not in Babylon. You'll find it here:

https://github.com/BabylonJS/Babylon.js/tree/master/dist

[MauJovi]

12 hours ago, Dad72 said:

poly2tri is an external file and is not in Babylon. You'll find it here:

https://github.com/BabylonJS/Babylon.js/tree/master/dist

But I already included both 

[Dad72]

Maybe a bug then. I do not know why you got this error.

have you try to create a playground that we can see what's wrong.

[MauJovi]

Here it is

http://www.babylonjs-playground.com/#1LGENM#0

I followed JKoehoorn suggestion, with push. Parsing the whole string i don't get the error but neither the polygon.

Maybe i'm doing something very dumb

[Dad72]

Your problem seems to be here. it is expected vector2 and not a string

    var contour = BABYLON.Polygon.Parse('');
	contour.push('655.55 120.85');
	contour.push('655.55 65.3');
	contour.push('708.75 65.3');
	contour.push('708.75 120.85');

I think it must be something like this:

http://www.babylonjs-playground.com/#1LGENM#1

I have no error, but I do not know the result you expect this playgroud. (This is something that I have no experience yet poly2tri)

[MauJovi]

Oh, i see...

Now the problem is the scale! Very large numbers.

Here it's ok: http://www.babylonjs-playground.com/#1LGENM#3

Thank you very much 

[MauJovi]

Hey, it's me again! haha

I needed to extrude my polygons, so I switched to this:

        shape.push(...Vector3 here...);
        var path = [
            BABYLON.Vector3.Zero(),
            new BABYLON.Vector3(0, 0.05, 0)
        ];
        var extruded = BABYLON.Mesh.ExtrudeShape("extruded", shape, path, 1, 0, 0, scene);
        extruded.material = new BABYLON.StandardMaterial("mat", scene);

But i need my shape to be closed. I saw a lot of examples, but none helped me. Could any of you?

Thanks

[jerome]

Don't be confused by this title post :

triangulation makes a plain polygon (so a surface) from a list of Vector3

extrusion makes a solid from a series of Vector3, what is a linear shape, not a surface

in other terms, extrusion extrudes a linear shape not a plain polygon. That said, extrusion can extrude any linear shape, closed or not. What is your problem ? Could you show us a PG repro ?

[MauJovi]

Thank you for your reply.

Simple example: I got four points that turn into a square and i wanted it to be a cube.

Using the code I posted before, it does the job, but i need my square to be closed at its top. Should I put another shape above it? This should be a little heavy to my application.

And sorry about being a noob at 3D, i may be using wrong terms...

[jerome]

well, to close an extruded shape, you've got two ways :

the most straigt forward is to use the CAP parameter of the extrusion method

if the way the cap is built doesn't fit your expectations, you can then use a polygon built by triangulation

please read the doc about extrusion to know how to add this cap :

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

http://doc.babylonjs.com/tutorials/Mesh_CreateXXX_Methods_With_Options_Parameter#extruded-shapes   if you use the MeshBuilder class instead of Mesh class, what is recommended

[MauJovi]

Yeah, I did it!

I was really using the wrong terms. If I looked for cap before... haha

Thank you again!