Mysterious .OBJ file doesn’t appear in my scene (But others do)

Questions
1

Hello,

I’m struggling to visualize an .OBJ file in my scene, I have .obj files comin’ from different sources, and one of them refused to show !

Let’s call them OK.obj & NOTOK.obj
I have a scene with :
objLoader, PerpectiveCamera & AmbiantLight

To setup the context : I tried/discover using three.js/editor, because on threeJS editor both are loading

  • NOTOK.obj have a scale different of OK.obj (so I defined object.scale.set(1000,1000,1000))

And then I’m trying to recreate the same configuration of camera than the three.js/editor but I do not succeed to view NOTOK.obj,

Do you have an idea of what I’m doing wrong ? what else can I try/check ?
NOTOK.obj (238.8 KB)
OK.obj (301.9 KB)

2

Using .obj format :full_moon_with_face:

Both files seem to load nicely in Blender, so it’s something most likely with the code (the scale is ~1000x different between the objects, but if you rescale the smaller one, it should show fine.)

3

Yess thanks,

Like I said I already try it to rescale x1000 but still it doesn’t appears,

It’s working in three.js/editor but not in my scene …

4

Hard to help without seeing the code though (at least the part used for loading the models) :sweat_smile:

5

The camera :

export function createCamera(sizes) {
    const camera = new PerspectiveCamera(
        50,
        sizes.width / sizes.height,
        0.1,
        10000,
    )
    camera.position.x = 0
    camera.position.y = 0
    camera.position.z = 320

    return camera
}

The light :

const light = new AmbientLight(0x404040);

The control :

export function createArcballControls(camera, canvas, scene) {

    const controls = new ArcballControls(camera, canvas, scene)
    controls.enableRotate = true
    controls.enableZoom = true
    controls.enablePan = true
    controls.enableAnimations = false // correspond to disable damping

    controls.setGizmosVisible(true)

    controls.setMouseAction('PAN', 0) // left
    // controls.setMouseAction('ZOOM',1) // middle 
    controls.setMouseAction('ROTATE', 2) // right

    controls.zoomSpeed = 2
    controls.panSpeed = 1
    controls.rotateSpeed = 1
    // controls.maxZoom = 120
    // controls.maxZoom = 120
    // controls.tick = () => controls.update();

    // controls.update()

    return controls
}

And the part to load the Obj :

   let object = await OBJloader.loadAsync(objUrl)
        //Go through all children of the loaded object and search for a Mesh
        object.traverse( function ( child ) {
            //This allow us to check if the children is an instance of the Mesh constructor
            if(child.isMesh ){
                f_moveFootPrint(child, standardMaterial)
                // if the points are already set we update the map
                child.name = "footPrint"
            }
        });
        console.log(object)
        
        importMesh = object
        console.log(importMesh.position)


       // add box  helper to the scene
         var helper = new THREE.BoxHelper( importMesh, 0xffff00 );
         scene.add( helper );
        

        scene.add(importMesh)


        camera.lookAt(importMesh.children[0].position)
6

That just one obj though - please show or replicate the complete code of how you load both obj’s after which one of them fails to show.

7

I’m using the same code to load them, just changing the URL to select the file

8

In that case - the code above does load both models, but one of them is 1000x smaller, and the code above does not scale it up to a proper scale :sweat_smile:

Also - if both models are loaded with that snippet, they are likely overlapping one-another - and since they are both rendered using MeshBasicMaterial, they will have no shading applied, so it may be impossible to tell one model from another in the scene.

1 Like
9

Okay I succeed to get the part of code which is problematic …

I have a code to Smooth the geometry which is the following :

export function setSmoothGeometry(geometry,tolerance=1 ) {
    // https://discourse.threejs.org/t/solved-how-can-we-smooth-model-loaded-with-objloader-i-e-not-flat-shading/5531/7
    
    const merged = mergeVertices(geometry,tolerance ); // this is a mystery
    // tempGeometry.mergeVertices();
    merged.computeVertexNormals();
    return merged
}

from this old topic : [SOLVED] How can we smooth model loaded with OBJLoader (i.e. not flat shading)? - #7 by Mugen87

I do not totally get what’s the tolerance for … But with the NOTOKAY file if I let the tolerance to 1 the geometry disappears