Mesh closest point #420
Mesh closest point #420
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2) Added a loop in the CloudClosestPoint instead of the IndexOf(Min()) method 3) Added an if statement to distiguish triangular faces and/or quad faces in the Mesh class
- from lists to arrays - code refinements - addition of polygon option (fan strategy)
Ngon doesn't get detected
…3 class) - added Ngon implementation (stellate method) (Notice: the vertices of the Ngon are being converted to Point3. Can't index a IEnumerable instead of a list)
Added Docstrings for all methods. Quad analysed as Ngon. Cloud closest point now static method.
Co-authored-by: iltabe <64929000+iltabe@users.noreply.github.com>
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Thank you for this contribution! Please check comments and update code accordingly. Mostly cosmetic and readibility comments.
Please also add the relevant unit tests in the appropriate test classes for the new methods. For closest point methods edge and point coincidence edge cases will be important to include.
There is also another PR open for PointInPolygon which may or may not be useful. #419
| /// <param name="trianglePoints">Triangle vertices.</param> | ||
| /// <returns>Boolean result (In - True , Out - False).</returns> | ||
| /// <exception cref="ArgumentOutOfRangeException">Thrown when trianglePoints is not 3 points.</exception> | ||
| private bool IsPointInTriangle(Point3 projection, Point3[] trianglePoints) |
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- Could take in a Polygon and check it has three vertices instead of an array of Point3.
- If you keep array as input, do you need to check the three points for collinearity?
- Rename input args to point and triangle for clarity
- What happens with coincident points with an edge? Are they in or out?
| @@ -547,6 +547,122 @@ private FaceData CountFaceEdges() | |||
| return data; | |||
| } | |||
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| /// <summary> | |||
| /// Checks if point is in or out a triangle. | |||
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inside or outside of a triangle
| /// <param name="point">Test point.</param> | ||
| /// <returns>Closest point to the triangle.</returns> | ||
| /// <exception cref="ArgumentOutOfRangeException">Thrown when trianglePoints is not 3 points.</exception> | ||
| private Point3 ClosestPointToTriangle(Point3[] trianglePoints, Point3 point) |
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- ClosestPoint is fine as method name on Mesh, trianglular polygon implied by input args
- Same comments regarding Polygon input vs point array as above
- Same comments regarding naming
| } | ||
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| /// <summary> | ||
| /// Finds the closest point to a mesh. |
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A bit more detail to differentiate the different ClosestPoint methods would be helpful in the summary docstring
| Point3 ClosestPointToNgon = ClosestPointToTriangle(trianglePoints, point); | ||
| TrianglesCP.Add(ClosestPointToNgon); | ||
| } | ||
| Point3 ClosestPoint = Point3.CloudClosestPoint(TrianglesCP, point); |
| { | ||
| // Ngon triangulation using the vertices' centroid and consecutive vertices to create the triangles | ||
| Point3 ngonCentre = Point3.AveragePoint(faceVertices); | ||
| var TrianglesCP = new List<Point3>(); |
| List<MeshVertex> meshVertices = Vertices; | ||
| // All faces check | ||
| IEnumerable<MeshFace> allFaces = this.Faces; | ||
| var closerPointToFaceList = new List<Point3>(); |
| for (int i = 0; i < faceVertices .Count; i++) | ||
| { | ||
| Point3[] trianglePoints = new Point3[] { ngonCentre, faceVertices[i], faceVertices[(i + 1)% faceVertices.Count] }; | ||
| Point3 ClosestPointToNgon = ClosestPointToTriangle(trianglePoints, point); |
| /// </summary> | ||
| /// <param name="points"></param> | ||
| /// <returns>The average point.</returns> | ||
| public static Point3 AveragePoint (IEnumerable<Point3> points) |
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Already implemented as Centroid() method in Point3
G-Shark/src/GShark/Geometry/Point3.cs
Line 520 in 76819e0
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| /// <summary> | ||
| /// Finds closest point to a test point from a cloud of points. |
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This should be moved to Point3 class as Point3.ClosestPoint(Point3[] points, Point3 testPoint). I don't think the "cloud" terminology is useful here as we do not have a specialized PointCloud class.
sonomirco
added
enhancement 📢
What type of PR is this? (check all applicable)
Description
This PR adds a ClosestPoint() implementation for meshes. The method takes a mesh and a test point and returns the closest point to the test point on the mesh. The algorithm finds the closest point to all the faces, then the absolute closest. This point can be either on a mesh vertex, mesh edge, or inside a mesh face. The method can be used with triangle meshes, quad meshes, and Ngon meshes. Any Ngons faces are triangulated using vertices' centroid and consecutive vertices. Quads are treated as Ngons. I did not work on the tests yet, I'd like some feedback first.
Related Tickets & Documents
Please use this format link issue numbers: Fixes #416
#416 (comment)
Added tests?
Added to documentation?