Blender quad export in glTF

[Josh]

There is supposedly a version of the Blender glTF export plugin available that supports quads:
https://github.com/KhronosGroup/glTF-Blender-IO/pull/622#issuecomment-536230661

Has anyone got this working? Quads are optimal for tessellation and I want to support this.

[Vida Marcell]

Where to download?

[reepblue]

52 minutes ago, Vida Marcell said:

Where to download?

It might be included the latest rolling release? I don't see any option to export as quads like I do with objs. Granted, my blender is out of date but seeing that that post was from 2019, I thought I would give it a look.

[Josh]

?

https://github.com/KhronosGroup/glTF-Blender-IO

[reepblue]

6 minutes ago, Josh said:

?

https://github.com/KhronosGroup/glTF-Blender-IO

Quote

Blender 2.80 and higher bundle this addon in the main Blender install package, so no 3rd-party install is required.

I don't see any options for quads here and it exports as triangles. 

[Vida Marcell]

See Josh, this is what i writed. I should have sended a picture too.

[Josh]

GPUs only render triangles, even when rendering quads. But if you open the file in a text editor, there should be an extension listed called "FB_ngon_encoding", or something like that.

[Vida Marcell]

Josh, what software other than blender is capable of that?

 

[reepblue]

It seems the edits were done on files that no longer exist.

[Josh]

I asked about it here:
https://github.com/KhronosGroup/glTF-Blender-IO/issues/1665

[Josh]

If you export as OBJ does that export quads?

[Josh]

It appears so:

# Blender v3.0.0 OBJ File: ''
# www.blender.org
mtllib untitled.mtl
o Cube
v 1.000000 1.000000 -1.000000
v 1.000000 -1.000000 -1.000000
v 1.000000 1.000000 1.000000
v 1.000000 -1.000000 1.000000
v -1.000000 1.000000 -1.000000
v -1.000000 -1.000000 -1.000000
v -1.000000 1.000000 1.000000
v -1.000000 -1.000000 1.000000
vt 0.625000 0.500000
vt 0.875000 0.500000
vt 0.875000 0.750000
vt 0.625000 0.750000
vt 0.375000 0.750000
vt 0.625000 1.000000
vt 0.375000 1.000000
vt 0.375000 0.000000
vt 0.625000 0.000000
vt 0.625000 0.250000
vt 0.375000 0.250000
vt 0.125000 0.500000
vt 0.375000 0.500000
vt 0.125000 0.750000
vn 0.0000 1.0000 0.0000
vn 0.0000 0.0000 1.0000
vn -1.0000 0.0000 0.0000
vn 0.0000 -1.0000 0.0000
vn 1.0000 0.0000 0.0000
vn 0.0000 0.0000 -1.0000
usemtl Material
s off
f 1/1/1 5/2/1 7/3/1 3/4/1
f 4/5/2 3/4/2 7/6/2 8/7/2
f 8/8/3 7/9/3 5/10/3 6/11/3
f 6/12/4 2/13/4 4/5/4 8/14/4
f 2/13/5 1/1/5 3/4/5 4/5/5
f 6/11/6 5/10/6 1/1/6 2/13/6

 

[Josh]

It looks like Blender will export diffuse, emissive, and normal in OBJ but not metal/roughness or AO. That's not too terrible:

# Blender MTL File: 'None'
# Material Count: 1

newmtl Material_MR
Ns 225.000000
Ka 1.000000 1.000000 1.000000
Kd 0.800000 0.800000 0.800000
Ks 0.500000 0.500000 0.500000
Ke 0.000000 0.000000 0.000000
Ni 1.450000
d 1.000000
illum 2
map_Bump Image_4.jpg
map_Kd Image_0.jpg
map_Ke Image_2.jpg

 

[Josh]

I think OBJ will work pretty well. Quads get saved with four indices, and anything else can be added to a second triangle mesh. I'm going to add built-in support for loading and saving OBJ files.

[Josh]

OBJ export from Ultra back to Blender:

[Josh]

Of course OBJ has no support for object hierarchies, so there is currently no way to get a quad-modeled character or hierarchal object into the engine without converting quads to triangles. Maybe Terathon's OpenGEX is an answer?