Mesh.dispose trigger Uncaught TypeError: Cannot read property 'meshes' of null

Bugs
1

Hello,
When I dispose meshes with mesh.dispose();
disposing meshes give me error:

Uncaught TypeError: Cannot read property 'meshes' of null
    at Array.e.splice (babylonjs.js:16)
    at Array.e.splice (babylonjs.js:16)
    at Array.e.splice (babylonjs.js:16)
    at Array.e.splice (babylonjs.js:16)
    at Array.e.splice (babylonjs.js:16)
    at Array.e.splice (babylonjs.js:16)
    at Array.e.splice (babylonjs.js:16)
    at Array.e.splice (babylonjs.js:16)
    at Array.e.splice (babylonjs.js:16)
    at Array.e.splice (babylonjs.js:16)

Here is my Code

    mesh.onDispose = function(){
        mesh = null;
    };
    mesh.dispose();

I unminified babylon.js and the issue is from here:

return (
    0 === e.length &&
        t.getScene().meshes.forEach(function (e) {
            e._markSubMeshesAsLightDirty();
         }),
      o);
3

It seems the scene is already disposed when you dispose the mesh, but without a repro in the Playground itā€™s going to be hard to say more.

2 Likes
4

It happen when only there is a mesh remains in scene. If more than one mesh exist, error not triggered.
I donā€™t have any scene.dispose or engine.dispose in my code, but it was working till a few weeks ago, I donā€™t know what happened? I did a few steps to optimize me scene from this page
It is a huge project, but your help let me think checking where scene customized. I will try to make it a Playground. Thanks @Evgeni_Popov

1 Like
5

I found the problem, but it is so weird!!!
One of my optimizations was reduce mapSize of shadowGenerator by FPS after loading each new mesh and this is the code:

        var FPS = engine.getFps().toFixed();
        shadowGenerator.mapSize = Math.min(512, parseInt(512 * (FPS / 60))) - parseInt(isSmallDevice() ? 64 : 0);

When I comment it no more errors found.
Can anyone give me another solution to reduce mapSize on lower power devices?

6

Are you doing this each frame? You should not, it recreates a number of textures under the hood, and the system may not have time to render a new frame that you already change for a new size. Also, you should not change the size if the difference in fps is not significant enough from the last time you changed the size. Thereā€™s no point to change from 503 to 494 for eg (if fps changes from 59 to 58).

7

New explore: the problem is from:
var FPS = engine.getFps().toFixed();
not the mapSize

@Evgeni_Popov

Are you doing this each frame?

No, After user adds a new mesh.

I played around with mapSize of shadowGenerator, it has huge effect on cpu usage.
My point is to reduce mapSize based on userā€™s device, doesnā€™t matter when and where for me, I just want higher quality for better devices, and higher fps for lower devices.
Thanks for considering the issue

8

I guess you will need to provide a repro in the Playground, I canā€™t understand why engine.getFps().toFixed() could be a problem.

9

Ok, I will try to make a Playground
@Evgeni_Popov

1 Like
10

At last I made it,
It happen when a mesh added and mesh accepts shadow, and after that change mapSize of shadowGenerator then remove mesh.
And I successfully made playground (check console)
Note: If another mesh exist in scene that accepts shadow, error will not shows up.

11

Thanks for the repro, hereā€™s the PR that will fix the problem:

1 Like
12

Thanks @Evgeni_Popov , Iā€™m not using .ts and so I did my own changes on babaylonjs.js file like so:
In case someone need:

(e.prototype.recreateShadowMap = function () {
                            var e = this._shadowMap;
                            if (e) {
                                var t = e.renderList;
                                this._disposeRTTandPostProcesses(), this._initializeGenerator(), (this.filter = this.filter), this._applyFilterValues();
                                //(this._shadowMap.renderList = t);
                                 if (t) {
                                    // Note: don't do this._shadowMap!.renderList = renderList;
                                    // The renderList hooked array is accessing the old RenderTargetTexture (see RenderTargetTexture._hookArray), which is disposed at this point (by the call to _disposeRTTandPostProcesses)
                                    if (!this._shadowMap.renderList) {
                                        this._shadowMap.renderList = [];
                                    }
                                    for (const mesh of t) {
                                        this._shadowMap.renderList.push(mesh);
                                    }
                                } else {
                                    this._shadowMap.renderList = null;
                                }
                            }
                        })