Blender export to Threejs.json bug, objects has been rotated

[gaoqi8985]

Description of the problem

when i use blender to export my scene to threejs, all
objects looks like rotated in my website.
but when i change the code of
'utils/exporters/blender/addons/io_three/exporter/api/mesh.py'
from line 23 to 37 like this :

everything is ok!

but why? and how to fixed ?

before I change the code:

after I change the code:

Three.js version

• Dev
• r88
• ...

Browser

• All of them
• Chrome
• Firefox
• Internet Explorer

OS

• All of them
• Windows
• macOS
• Linux
• Android
• iOS

Hardware Requirements (graphics card, VR Device, ...)

[mrdoob]

/ping @douglasppaz

[dougppaz]

@gaoqi8985 You export cameras too? Or just the objects?
If you rotate the camera, you can take the same result.

flip_axes's code commented isn't good solution. I created this pull request #12784 with a possible solution to our problems.

[gaoqi8985]

@douglasppaz
if you look the picture more careful, you will find that we can not take the same result by rotate camera,
in the picture 1, It is one face to three model, in the picture 2, it is three model face to one, and I can tell you ,the model in picture 1 , the model is look at a little upper, and in picture 2 ,they look at a little down,
It looks like every model rotated by it's self center, or mirrored 2 axis by it self center.
Could you catch up with me ? my English is poor.

[muhammedmaruf]

if dir == XZ_Y:
a = (a[0], a[2], -a[1])
elif dir == X_ZY:
a = (a[0], -a[2], a[1])
elif dir == _XY_Z:
a = (a[0], a[1], a[2])

When I removed the X and Y negative values, I saw that the problem was solved.
But I do not know if it will cause another problem.

[giangm9]

@muhammedmaruf sure it will, when i try to export a skinned mesh and play animation, the meshes transfrom incorrectly, so i tried to use gltf extesion instead

[Mugen87]

Hey guys. Please note #14117

[Mugen87]

The JSON Blender exporter has been removed with R93 (#14117).

Also see: https://threejs.org/docs/#manual/introduction/Loading-3D-models