Computer Graphics Stack Exchange
Computer Graphics Stack Exchange

Questions tagged [triangulation]

30 questions
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5 answers

Why are quads used in filmmaking and triangle in gaming?

In film school, in the classes of 3D modeling, I was told that when we model something for films we maintain topology of 4 edged polygons. Any polygon which has more or less than 4 edge/vertex is considered bad and should be avoided. Whereas if the…
Santosh Kumar
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14
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1 answer

How to triangulate from a Voronoï diagram?

I computed a Voronoï diagram from a set of points (with Boost.polygon). I try to find a Delaunay triangulation, connecting each cell center for each Voronoï edge, but I miss some edges. In the following image, the red dots are my initial points,…
arthur.sw
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12
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3 answers

How can I concentrate points in areas of higher curvature?

How can I distribute points over an implicit surface, to concentrate them more densely in areas of higher curvature? I've considered adding points randomly and rejecting points not required based on the curvature, but I'd like to know if there is a…
trichoplax is on Codidact now
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How can I perform a triangle inside test in polygon meshes?

I have 3 vertices (V1, V2, V3) randomly selected on a regular triangle mesh. For these 3 vertices, I have computed the geodesic distance and the path (by using Dijkstra) among them and formed a triangle-like surface as in the above figure. Now, I…
mkocabas
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8
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1 answer

What is the definition of a Half Edge?

I ran into half-edges as part of the result of a Delaunay Triangulation library, but can't find an actual definition of what one is. I understand vertices, edges and faces, but can't find a concrete definition of a half-edge.
Mark A. Ropper
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8
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1 answer

Computational Geometry - Triangulation

I'm trying to triangulate complex 3D objects, that may have holes in them. Now I tried going over the problem myself, after a few hours I didn't get anything that would work all of the time, so I've been searching around and without much luck. Does…
Aaron
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7
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1 answer

What is this triangle sub-division scheme called?

I have thought of a triangle sub-division for the purpose of smooth triangulation (no popping) over time on the fly. I think it is very likely the scheme is already invented and has a name but I can´t seem to find it. Sub-division is made on…
Andreas
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6
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4 answers

How to decide which way to triangulate a quad?

Apologies if this is a dumb question... but given four arbitrary (non-coplanar) points in 3D space, there are obviously two different ways to triangulate the quad that they form. One triangulation may produce much more natural results than the…
andygeers
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5
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1 answer

Draw angles lines in raster graphics using bresenham line algorithm

I at the moment trying to draw some angled lines using bresenham line algorithm which can circulate a 2d array of size 21x21, as a line angled from 0 - 2pi. So the idea is that the program has to output the values which the lines pass through in…
Bob Burt
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4
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1 answer

What is better to use for real-time computing Mesh - Plane intersection points, GPU or CPU?

I want to write plugin (library) for Unity3d (it doesn't matter which framework I will choose for this, question is ), for cutting arbitrary mesh with plane (for simplicity it will be plane for beginning). There are following steps: 1) check every…
Ivan Yakovlev
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4
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2 answers

Combination of Triangles and Quads in a mesh

Is it topological correct to combine triangles with quads to form a mesh. If not, why?
user55844
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4
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2 answers

How to determine the object-to-world matrix

I want to ray trace a triangular mesh that I load from a file. The vertices' coordinates are expressed in the reference frame associated with the object (i.e the mesh) and I don't know the object-to-world matrix. Is there a way to calculate this…
S.E.K.
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3
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1 answer

Subdivide a triangle along its UVs

I'm looking into a problem that first occured very trivial to me, but i got stuck and it's becoming a major issue right now. I'd like to subdivide a triangle by its given UVs, e.g. if the UVs are going from -n...+m or if they are greater than 1. So…
Intrins
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Compute angles and thereby endpoints in a raster grid?

I am at the moment having some issues with computing an endpoint in a raster grid that is also a valid position in a graph. I am trying to draw a line between these two points, but as the point I am computing becomes negative, its position becomes…
Bob Burt
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3
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1 answer

Smooth triangular mesh interpolation

I am looking for an algorithm which would smoothly interpolate triangles of a mesh (computed by Delaunay triangulation) where each vertex has some value (elevation in my case). I need it for PDAL where I want to try to implement it. Its current…
Martin Ždila
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