Sample points from textured mesh

[sebaFP]

Hi,
I need to generate a point cloud from a textured obj, I can generate it but without colors.
Can I generate a sample but getting vertex color from texture?
Thanks!

[griegler]

Textures are not considered yet in sample_point_cloud_*. It shouldn't be hard to implement. Would you be interested in contributing a PR with our guidance?

[Xelawk]

Textures are not considered yet in sample_point_cloud_*. It shouldn't be hard to implement. Would you be interested in contributing a PR with our guidance?

I also really need this feature

[ShougangShen]

Hi,
I need to generate a point cloud from a textured obj, I can generate it but without colors.
Can I generate a sample but getting vertex color from texture?
Thanks!

Hello, I have the same requirement as you. Have you realized this feature?

[Xelawk]

Hi,
I need to generate a point cloud from a textured obj, I can generate it but without colors.
Can I generate a sample but getting vertex color from texture?
Thanks!

Hello, I have the same requirement as you. Have you realized this feature?

Yep, I have the code to do this operation. If you need it, please contact me :-)

[MaybeOjbk]

Hi,
I need to generate a point cloud from a textured obj, I can generate it but without colors.
Can I generate a sample but getting vertex color from texture?
Thanks!

Hello, I have the same requirement as you. Have you realized this feature?

Yep, I have the code to do this operation. If you need it, please contact me :-)
can you give me your code ?

[Xelawk]

Hi,
I need to generate a point cloud from a textured obj, I can generate it but without colors.
Can I generate a sample but getting vertex color from texture?
Thanks!

Hello, I have the same requirement as you. Have you realized this feature?

Yep, I have the code to do this operation. If you need it, please contact me :-)
can you give me your code ?

OK, Tell me you email

[cr139139]

Hi,
I need to generate a point cloud from a textured obj, I can generate it but without colors.
Can I generate a sample but getting vertex color from texture?
Thanks!

Hello, I have the same requirement as you. Have you realized this feature?

Yep, I have the code to do this operation. If you need it, please contact me :-)

Can I also get the code for the operation? I'll send a note to your gmail address.

[Xelawk]

Feel free to the repo: https://github.com/Xelawk/mesh_utils
If it does help you, pls star it, Thanks

[cr139139]

Of course! Thanks a lot! By the way, I have one more question. I saw your code and didn't find out how to use it. Can you show me a sample usage if possible? I'm really sorry for asking this. I'm not a coding guru...

…

On Sat, Jul 10, 2021 at 12:04 AM Xelawk ***@***.***> wrote: Feel free to the repo: https://github.com/Xelawk/mesh_utils If it does help you, pls star it, Thanks — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#2483 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AJXNZ6EXEYT3T2HTWC6GFCTTW4FWXANCNFSM4SSPN3CA> .

[benjaminum]

Thanks for sharing a solution.

[NiuCY]

I think this way is better:
mesh = trimesh.load_mesh(mesh_path)
samples, face_idx, colors = trimesh.sample.sample_surface(mesh, 30000, sample_color=True)

[nikste]

It seems @Xelawk solution does not work anymore with the new version of Open3d (or I am doing something wrong)
@benjaminum @griegler can we reopen this and do you have some pointers how this could be implemented for open3d?

[nikste]

so I guess I can put it there:

Open3D/cpp/open3d/geometry/TriangleMesh.cpp

Line 476 in fcf98ee

if (has_vert_color) {

check if there has_textures() returns true and then read the color from the texture.
how to arrive at the right pixel coordinate though to read the color and add to the resulting point cloud color?
what does triangle_uvs[triangle_idx] ?

[benjaminum]

Hi @nikste
The steps to implement this would be

1. Remember triangle idx for each point
2. Compute triangle barycentric coordinates for the sampled point from the point xyz and the triangle vertices xyz
3. Compute UV coordinates using the triangle_uvs with the weights from the barycentric coordinates
4. Look up the color values in the texture at the respective UV coordinates