Questions tagged [vertices]

A vertex (plural: vertices) has a slightly different meaning depending on context. Computer graphics - data structure that describes position of a point in 2D or 3D space. Geometry - point where higher-dimensional geometric objects meet; Graph theory - fundamental unit of graphs;

A vertex in computer graphics is a data structure that describes certain attributes, like the position of a point in 2-Dimensional or 3-Dimensional space, at multiple points on a surface.

In geometry, a vertex is a point where two or more curves, lines, or edges meet. As a consequence of this definition, the point where two lines meet to form an angle and the corners of polygons and polyhedra are vertices.

In mathematics, and more specifically in graph theory, a vertex or node is the fundamental unit of which graphs are formed (usually represented by a circle with a label)

471 questions
3
votes
1 answer

Creating Graph class in C#

I have a task to create Graph class in C#, that would have following properties: private List vertices; private List> adjacencyMatrix; private int n; n is the number of nodes, the rest is self explanatory I believe. The class…
MWPodgorni
  • 83
  • 2
  • 9
3
votes
1 answer

How to access single vertices of mesh loaded with GLTFLoader in Three.js

I am loading a glb-File using GLTFLoader in Three.js: Before I was using the JSONLoader. Accessing the vertices of the loaded mesh was easy: meh.geometry.vertices But when looking at the mesh loaded with GLTFloader, I just can not find, where the…
3
votes
4 answers

Accessing mesh vertices performance issue

I am having trouble with this code running slow (around 250ms to execute the loop) The mesh.triangles.Length is 8700. I am using c# on the latest Unity platform (version 2018.2.3). I suspect this is because I am switching between two arrays for…
Dave502619
  • 57
  • 6
3
votes
1 answer

Does the Dijkstra algorythm need to check all vertices?

I recently had to take a look at the Dijkstra algorithm and it's proof. The proof of the algorithm terminates in all sources I could find with the equality of quantity of all vertices and the quantity of all vertices visited (e.g. R=V or S=V).…
BenStudio
  • 51
  • 1
  • 4
3
votes
1 answer

OpenGL z value. Why negative value in front?

Opengl has right-hand coordinate system. It means z values increase towards me. right-hand coordinate system I draw two triangles: float vertices[] = { //position //color //triangle 1 0.0f, 1.0f, -1.0f, …
3
votes
1 answer

How to draw or plot a mesh using the mouse in JavaFX which can then be textured and deformed?

I am trying to implement a tool into my application. the tool would allow the user to plot a triangle meshes using the mouse. I have looked everywhere for a way to do this, tutorials, examples, etc and have not been successful. I have seen the FXyz…
Lunayah
  • 110
  • 7
3
votes
2 answers

mapping a texture on a square (Android)

Im new to openGL, and im trying to map an texture to a square. I followed NeHe's tutorial on texture mapping here: http://insanitydesign.com/wp/wp-content/uploads/lesson06.zip Right now i see my image...but its not mapping correctly. Heres the…
jfisk
  • 6,125
  • 20
  • 77
  • 113
3
votes
2 answers

igraph: Remove vertices from layout

I want to create a visualization of a graph at 4 steps, i.e. different points in time. The positions of my vertices (nodes) should always stay the same (use the positions of the full graph). All I want is to remove some vertices from the R igraph…
Rnaldinho
  • 421
  • 2
  • 6
  • 15
3
votes
1 answer

Three.js: Get updated vertices with morph targets

I've got some morph targets working: https://jsfiddle.net/3wtwzuh3/2/ (Use the slider control to see the morph) However, I'd like to be able to access the new positions of the vertices after the morph. If you notice in the linked example, I am…
AlexKempton
  • 1,648
  • 15
  • 28
3
votes
1 answer

Three.js - Merge multiple geometries/meshes removing common areas

I´m trying to merge two geometries/meshes (red and blue) into a unique one. But after creating a new geometry and applying geometry.merge() I found that all the inner vertices and faces are still there (the green area). I would like to remove all…
spacorum
  • 495
  • 6
  • 16
3
votes
2 answers

Algorithm for classification of vertices in a graph based on their weight

I have the following complete weighted graph, where each weight represents the probability of a vertice belonging to the same category as the next. I know a priori the category for which some of the vertices belong to; how would I be able to…
3
votes
1 answer

igraph initialisation with weights

How can I initialise an igraph with weights? This is what I have cr = csv.reader(open("atlas.csv","rb")) mapping = {} for row in cr: if int(row[2]) == 1: continue source = int(row[0]) target = int(row[1]) if source in…
MTA
  • 739
  • 2
  • 9
  • 29
3
votes
1 answer

Leaflet - draw polyline vertices only

The title is quite clear, I'm using Leaflet and I need to show only the vertices of a polyline. For exemple see this image : Currently I can only have the black line, I'd like only the red squares. Using markers is not an option for performance…
Tim Autin
  • 6,043
  • 5
  • 46
  • 76
3
votes
1 answer

XNA - Using Dynamic Vertex Buffer and only four(4) vertices

Just a quick question on drawing quads. I'm currently using: GraphicsDevice.DrawPrimitives(PrimitiveType primitiveType, int startVertex, int primitiveCount); This draws my quads perfectly fine but the only way I can make it…
Robert Kaufmann
  • 768
  • 1
  • 9
  • 21
3
votes
1 answer

How to create a collada file from an objects faces' vertices information?

I have a project that requires me to export a model in a .dae Collada format. I am struggling to figure out how to do this. I have been trying to use pyCollada to do so, but I have limited experience with 3D modeling and the file structure is…
Skylion
  • 2,696
  • 26
  • 50