Questions tagged [polygon]
The polygon tag has no usage guidance.
17 questions with no upvoted or accepted answers
10
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How to describe the bi-directional links for the Weiler-Atherton algorithm?
My postscript interpreter currently implements the Hodgeman-Sutherland clipping algorithm but this is limited to simpler shapes and doesn't have a provision for utilizing various winding-number rules. ...
- 1,378
3
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0
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199
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Generate polygons after marching squares in parallel
I've implemented the marching squares algorithm following Wikipedia's https://en.wikipedia.org/wiki/Marching_squares. The output I got is a set of edges, to which each contouring cell contributes 0, 1,...
- 31
3
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What is a good algorithm, and framework, to calculate centres of gravity or mass (cog)?
I'd like to take an photograph, subdivide it into a tesselation, either of squares, or (ideally), hexagons, and then find the centre of gravity (or, if you prefer, centre of mass) of each cell of the ...
- 131
2
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55
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Divide mesh according to level of detail
Background
I need to remesh by OpenVDB, like what Blender remesh does:
Voxel
Uses an OpenVDB to generate a new manifold mesh from the current geometry while trying to preserve the mesh’s original ...
- 133
2
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0
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1k
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Scan Line Polygon Fill Edge Table Entry Order
I am trying to figure out the correct order between edges on edge table on scan line polygon fill.
One example here on Y=1 takes first ...
- 121
1
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27
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Algorithm for real-time rendering of complex 2D polygons under dynamic transforms on GPU
I would like to know what the state-of-the-art approach is for rendering complex (as in non-simple) 2D polygons on the GPU.
My exact use case is a GeoJSON renderer that is supposed to be able to ...
- 11
1
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0
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40
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How to get a polyline from an image with consistent winding number
I am trying to find an algorithm for the following problem.
Assume we have a black and white image. The image contains a white region that encloses a space. This space may be concave but it has no ...
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1
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54
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The ploygon width parallel to the x axis as a function of the y ordonate?
Considering a polygon with n vertices as input.
I need to calculate the integral of the form
\[\int_A p(y) dA \] where $p(y)$ is a piecewise polynomial function of $y$.
May be if I could find the ...
- 111
1
vote
0
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170
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How to do a scanline fill with a self intersecting polygon?
I have a bezier curve and would like to draw it's stroke. To do that, I planned to approximate the stroke to a polygon and fill it with a scanline algorithm. While I feel confident about implementing ...
- 111
1
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65
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Convert a polygon mesh to a bspline surface
Problem:
Getting a polygon mesh as input, I have to construct a surface that looks exactly to the given input. My task is to generate a b-spline surface that exactly looks like the connected polygon ...
- 131
1
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338
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How can I convert a shape made out of pixels to vertices
I'm trying to implement the solution to get the minimum dissection into rectangles of a rectilinear polygon.
My shape is made out of pseudo-pixels (different width/height) but for the moment let's ...
- 183
1
vote
2
answers
213
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Convert triangulated object to a polygonized object
Is there an efficient algorithm to convert a 3D object described with a set of triangles to a 3D object described with a set of polygons. Polygons can have an arbitrary number of points, more is ...
- 111
0
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0
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44
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AMD GPU specific triangles disappearing by subsequent draw calls in same frame
we have a Windows/DirectX11 2D Renderer that paints textured triangles to the screen from back to front. There is no face-culling or depth test activated.
Now on AMD GPUs it happens randomly that an ...
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73
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How would you represent a mesh with tris and quads?
My understanding is that, while subdivision algorithms like Catmull-Clark can work for any polygonal mesh (including triangles) it's preferable to start with a quad mesh.
Currently my rendering engine ...
- 299
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19
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Turning layered curves to polygon mesh?
I am confronted with the problem to render 3D representations for objects marked on microscope slices.
So I have a set of aligned polygons in parallel planes from tracing the outline of the object in ...
- 141
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47
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Cover a polygon with least amount of parallelograms
I am solving the task that is as follows:
Input: a polygon. Can be any kind of polygon without self intersections. Can be a non-convex and with holes inside.
Goal: to cover it with 2 (at least) or ...
- 101
0
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99
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In a polygonal mesh 3d model which consist of triangles is it possible to separate different objects?
I have a 3d city model that is a collada file which consist of many triangles. When I select the model in a 3d software all buildings are selected. But I want every building to be selectable ...
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