Thread problem with BABYLON.SceneLoader.ImportMesh

[saldukoo]

Hello. Having a problem with BABYLON.SceneLoader.ImportMesh.

I think it is thread related. But i dont know how to fix it. Here's my code:

function Player() {
    this.mesh = null;
} 

...

player = new Player();
BABYLON.SceneLoader.ImportMesh("", "/assets/game/imports/", "player.babylon", scene, function (newMeshes, particleSystems, skeletons) {
     player.mesh = newMeshes[0];
});

Here i am declaring the player class and then using it inside the createScene() -function. This works just fine in the render loop.

Now i want to move the import statements to the player class. Consider the following adjustment:

function Player() {
    this.mesh = null;
    this.addTo = function(scene) {
       BABYLON.SceneLoader.ImportMesh("", "/assets/game/imports/", "player.babylon", scene, function (newMeshes, particleSystems, skeletons) {
           this.mesh = newMeshes[0];
       });
    };
} 

...

player = new Player();
player.addTo(scene);

This instead, doesn't work. The render loop thinks player.mesh is null regardless of time. How should i fix this thing?

[wladimiiir]

Hi,
I believe you are missing bind for your function to correctly set this inside the function.

this.addTo = function(scene) {
       BABYLON.SceneLoader.ImportMesh("", "/assets/game/imports/", "player.babylon", scene, function (newMeshes, particleSystems, skeletons) {
       this.mesh = newMeshes[0];
    }.bind(this));
}.bind(this);

Cheers.

[RaananW]

Hi,

JavaScript has no threads, It has asynchronicity. which is much nicer

When you add the player to the scene, the mesh is not yet set, since it first needs to be loaded and parsed. You can only add the player AFTER the mesh was assigned. To do this, simply move your addTo call inside the success callback:

function Player() {
    this.mesh = null;
    var that = this;
    this.addTo = function(scene) {
       BABYLON.SceneLoader.ImportMesh("", "/assets/game/imports/", "player.babylon", scene, function (newMeshes, particleSystems, skeletons) {
           this.mesh = newMeshes[0];
           that.addTo(scene)
       });
    };
} 

...

player = new Player();

This is a classic callback/async JS question. 

[saldukoo]

Hi RaananW. I tried that but unfortunately didn't work. The ImportMesh refuses to work unless it's direcly inside createScene function. This is weird. Maybe I am setting up my class wrong? Is there an example somewhere?

 

[RaananW]

oh! wait, That was wrong

function Player() {
    this.mesh = null;
    var that = this;
    
    this.addTo = function(scene) {
       BABYLON.SceneLoader.ImportMesh("", "/assets/game/imports/", "player.babylon", scene, function (newMeshes, particleSystems, skeletons) {
            that.mesh = newMeshes[0];
        });
    };
} 

...

player = new Player();
player.addTo(scene);

I just realized what you were trying to do

[saldukoo]

Yes! That works, thank you.

I hate callbacks.