Imported mesh to BABYLON.Mesh

[Aidoru]

Hello,
I have a problem to use CSG on imported meshes, here's my code:

    var a;
    var b;

    BABYLON.SceneLoader.ImportMesh("", "./public/Models/", "model1.stl", scene, function (newMeshes) {
        // Set the target of the camera to the first imported mesh
        camera.target = newMeshes[0];
        a = newMeshes[0];
    });



    BABYLON.SceneLoader.ImportMesh("", "./public/Models/", "model2.stl", scene, function (newMeshes) {
        // Set the target of the camera to the first imported mesh
        //camera.target = newMeshes[0];
        b = newMeshes[0];
    });


    var aCSG = BABYLON.CSG.FromMesh(a);
    var bCSG = BABYLON.CSG.FromMesh(b);

"var a" and "var b" are undefined and Debug told me that

 "BABYLON.CSG: Wrong Mesh type, must be BABYLON.Mesh"

 

Is there any method to convert imported mesh to BABYLON.MESH?

 

Thank you very much

[Guest]

Hello and welcome

(you were not in the right sub forum (I moved the topic already))

So in your example, ImportMesh is an asynchronous function which means that a and b will be set but later when the file will be read. So you have to move to something (not tested) like that:

  var a;
    var b;

    BABYLON.SceneLoader.ImportMesh("", "./public/Models/", "model1.stl", scene, function (newMeshes) {
        // Set the target of the camera to the first imported mesh
        camera.target = newMeshes[0];
        a = newMeshes[0];
        BABYLON.SceneLoader.ImportMesh("", "./public/Models/", "model2.stl", scene, function (newMeshes) 
        {
        // Set the target of the camera to the first imported mesh
        //camera.target = newMeshes[0];
        b = newMeshes[0];

    var aCSG = BABYLON.CSG.FromMesh(a);
    var bCSG = BABYLON.CSG.FromMesh(b);
    });
    });

 

[brianzinn]

It looks like you want to load the meshes at the same time, based on your comment about setting the target.  There may be a race condition - it's untested:

var a;
var b;
var meshesLoaded = 0;

BABYLON.SceneLoader.ImportMesh("", "./public/Models/", "model1.stl", scene, function (newMeshes) {
    a = newMeshes[0];
    meshesLoaded++;

    // Set the target of the camera to the first imported mesh
    if (meshesLoaded === 1) {
        camera.target = newMeshes[0];
    } else if (meshesLoaded === 2) {
        // CSG
    }
});


BABYLON.SceneLoader.ImportMesh("", "./public/Models/", "model2.stl", scene, function (newMeshes) {
    a = newMeshes[0];
    meshesLoaded++;

    // Set the target of the camera to the first imported mesh
    if (meshesLoaded === 1) {
        camera.target = newMeshes[0];
    } else if (meshesLoaded === 2) {
        // CSG
    }
});

I think a better way is with promises and it's easier to make a more generic solution.  Here is a commit that loads all the materials and returns when they are all loaded.  So, you could write a method that takes a list of Models and returns when they are all loaded.  Look for these lines:
mtlPromises.push(new Promise((resolve, reject) => {...}));

and
Promise.all(mtlPromises).then(() => {...});
https://github.com/BabylonJS/Babylon.js/commit/82f8addaae0c84e35adf289b122d3423dd9d59c5#diff-2209ca1e0591b2fc9b58edd4295b48eb