isl-org/Open3D

Copy UV coordinates from a reference mesh.

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#6,625 opened on Jan 26, 2024

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feature requestgood first issuemesh

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Description

Checklist

Proposed new feature or change

In many mesh processing workflows, UV coordinates are not preserved (e.g. mesh simplification). UV coordinates are required for many downstream tasks. One way to propagate UV coordinates through mesh processing workflows is by copying them from the original mesh. Here is an outline:

  1. Mesh A is processed to mesh B. Mesh A contains UV coordinates (and textures), but mesh B does not have them.
  2. Call meshB.InterpolateTextureCoordinatesFrom(meshA). This does:
  • Create a ray casting scene with mesh A.
  • For each vertex in mesh B, find nearest point in mesh A.
  • Assign UV coordinates of nearest point in mesh A to the vertex in mesh B.
  • Optionally, copy over any textures from mesh B to mesh A.

References

No response

Additional information

It may be necessary to convert from per-triangle UVs to per-vertex UVs (or vice versa). The following code shows an example of how to make that conversion: https://github.com/isl-org/Open3D/blob/main/cpp/open3d/visualization/rendering/filament/TriangleMeshBuffers.cpp#L614

Contributor guide

Research direction
Implement the proposed InterpolateTextureCoordinatesFrom method. Use Open3D's ray casting functionality to find the nearest point on mesh A for each vertex in mesh B. Assign UV coordinates accordingly. Pay attention to conversion between per triangle and per vertex UVs, as referenced in the provided code snippet from TriangleMeshBuffers.cpp. Test with sample meshes.
Tech stack
cpppython
Domain
data
Issue type
Feature
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-2 days
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Fresh
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
Basic knowledge of Open3D mesh APIUnderstanding of UV coordinatesFamiliarity with ray casting
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
70