locationtech / locationtech/jts
ConformingDelaunayTriangulationBuilder poor triangulation for single-triangle input, possibly for any already-Delaunay set of constraints.
Nobody has claimed this yet.
- Dominant language
- Java
- Stars
- 2.2k
- Forks
- 475
- Avg merge
- 14d 10h
- Merged PRs (30d)
- 1
Description
Starting from a single triangle, passing the 3 vertices as sites with empty constraints reproduces the same triangle.
No constraint result, same as original triangle:
Adding the triangle's 3 edges as constraints nominally succeeds, but produces 3 unnecessary and incorrect triangles, one of which has zero area.
I have seen similar issues with constraints that happen to correspond to a triangulation of the sites which is already Delaunay.
I could add some multiple triangle examples if that would helpful.
Code:
https://github.com/palisades-lakes/jts-issues/blob/main/src/main/java/jts/CDTBIssues.java
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start with the reproduction in src/main/java/jts/CDTBIssues.java and run it against ConformingDelaunayTriangulationBuilder. Compare the unconstrained triangle output with the output when its three edges are supplied as constraints, then trace the builder's handling of already-Delaunay constraints. Done means no unnecessary or zero-area triangles are produced for the reported case.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- java
- Domain
- computer-graphics
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Quiet
- Clarity
- Mostly clear
- Newbie friendliness
- 45/100