Delaunay Triangulation

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  • Опубліковано 8 тра 2020
  • Creating quality meshes is a task common in computer graphics and numerical analysis like finite element methods. Among many others, one technique of much importance is the Delaunay triangulation.
    In this video, we try to introduce you to the Delaunay triangulation and its computation by the Bowyer-Watson algorithm. This video focuses more on the computational part. So, let's enjoy the video!

КОМЕНТАРІ • 47

  • @HoaDucPham
    @HoaDucPham 3 роки тому +12

    I understand it this way:
    for a given number of points, you draw a triangle whose circumference should cover all the points
    1. You take your first point randomly, connect it to each vertex of the first triangle.
    2. If a triangle contains a point within its circumference, then you delete that triangle by deleting an edge which connects the chosen point to the vertex of the first triangle.
    Otherwise, you keep the edge- and the point becomes the new vertex of a new polygon that we will do the same thing with the second point.
    3. Keep doing that till you have the ultimate outer polygon that has vertices match the outer points and the tri-elements with vertices match the inner points.
    (*) easily see that we should take the initial points from the outer ones then work our way in.

  • @sanjanakomateswar8191
    @sanjanakomateswar8191 2 роки тому +3

    Amazing video.Gave me a excellent understanding and visually explained.Thank you sooo much, it was difficult to gain this understanding as not much people have written or made of video about it so clearly.

  • @SecondThread
    @SecondThread 4 роки тому +4

    How do we know that any edges in the 'Super Triangle" aren't relevant? It is possible for there to be some edges on the super triangle that connect to points not on the convex hull of the set of interest, isn't it?

    • @leonardoherfianto897
      @leonardoherfianto897 3 роки тому +4

      Contruct the Super Triangle
      1. find the centeroid from all points
      2. create an axis heading to 3 angle (90, 210, 300) degree
      3. find all max projection axis for all points that align to our 3 axis (use dot product) and scale it to 1,5 or bigger;
      4. the step 3 will result 3 max projection point.
      5. find intersection point of all 3 max projection point.
      6. the intersection point is your super triangle.

  • @tanzeelhassan2934
    @tanzeelhassan2934 3 роки тому +1

    Just wow, the video is awesome!

  • @dalskiBo
    @dalskiBo 3 роки тому

    Lovely video, thanks SCIco.

  • @dalskiBo
    @dalskiBo 3 роки тому +8

    Brilliant video, thanks for sharing; concise intro & unusually dark music.

  • @mwprogrammer
    @mwprogrammer 2 роки тому

    Thanks for low key saving my exam.

  • @Undead34
    @Undead34 2 роки тому

    Thank you, i love this video

  • @sajedehkebriti3548
    @sajedehkebriti3548 3 роки тому

    Awesome! Just come with other movies! It was really intuitive

  • @bln3615
    @bln3615 3 роки тому +1

    Thank you, if you could do one also on building weighted diagrams that would be great.

  • @ian.ambrose
    @ian.ambrose Рік тому

    Beautiful video.

  • @muhammadbilalshahid8010
    @muhammadbilalshahid8010 2 роки тому

    Awesome, Thanks.

  • @nataliazhang4309
    @nataliazhang4309 2 роки тому

    Thanks! Nice video!

  • @louise1021
    @louise1021 Рік тому

    Amazing!!!

  • @amolsamota9104
    @amolsamota9104 3 роки тому

    Great work

  • @AlhambraDream
    @AlhambraDream 3 роки тому

    this is awesome

  • @seunghunlee2598
    @seunghunlee2598 4 роки тому +1

    Hi! your video help to me, but I can't understand what is the standard for find new circumcircle (02:00)

    • @ricardopieper11
      @ricardopieper11 4 роки тому

      If you mean "how to find the circumcircle", wikipedia has the answer en.wikipedia.org/wiki/Circumscribed_circle (Circumcenter coordinates, cartesian coordinates)

    • @ricardopieper11
      @ricardopieper11 4 роки тому

      You can use it like I do here: editor.p5js.org/ricardopieper/sketches/M2lEVxA64
      look at the circumscribedCircle function. This code actually has all the pieces you need to implement the algorithm in the video, together with relevant wikipedia sources.

    • @jamesj2869
      @jamesj2869 3 роки тому

      Ricardo Pieper have you seen Fade2D code (in case) it is in C++. I want to ask some question if in case someone used it

  • @stynod7422
    @stynod7422 2 роки тому +1

    How do you know where to put the vertices of the super triangle??

    • @delicate6930
      @delicate6930 2 роки тому

      i just put the vericies at a number i knew was outside my domain

    • @supergreatoli2
      @supergreatoli2 Рік тому

      I made a square containing all my points and then drew the equilateral triangle which circumscribes the square

  • @NeZversSounds
    @NeZversSounds Рік тому

    From this presentation, which looks awesome, I gather that for this to work, the points need to be more or less evenly spaced, not truly random. I don't see how it could work with points that are forming clusters, it looks like they will be in circles of cluster's outside vertices.

    • @robotlegs
      @robotlegs 6 місяців тому

      It actually works better when they're random because you're less likely to encounter infinite-radius circles (i.e. 3 colinear points). As long as your super-triangle encloses all your points, the algorithm will find all of them.

  • @temesegenabuhay9408
    @temesegenabuhay9408 3 роки тому

    is there any rule to draw the circumcircle for the triangle... Mr

    • @Alkis05
      @Alkis05 3 роки тому

      The only rule is for the circle to contain at least one vertex.

  • @msssivadas10
    @msssivadas10 4 роки тому +1

    Voronoi diagrams can be computed using the same methods of finding Delaunay triangulation.

    • @manuarteteco6153
      @manuarteteco6153 3 роки тому

      seriously? That is helpful, even tough I can't really see how right now

    • @VADroidTS555
      @VADroidTS555 3 роки тому

      @@manuarteteco6153 They share duality.

  • @husseinjafarinia224
    @husseinjafarinia224 2 роки тому

    I think Joker's gonna attack in the end

  • @Rajgrv100
    @Rajgrv100 2 роки тому +1

    Bro can you do a video about Frontal advancement method? I'm a mallu too :-) , nice video.

  • @user-zk1hp1wp3s
    @user-zk1hp1wp3s 3 роки тому +1

    Scary sounds

  • @jamesj2869
    @jamesj2869 3 роки тому

    code: geom.at (Fade2D code)

  • @subject2749
    @subject2749 Рік тому

    great video odd music choice though

  • @roman_roman_roman
    @roman_roman_roman 3 роки тому +3

    Why music is so scary?...

  • @lovegarbage
    @lovegarbage 2 роки тому

    The music added nothing apart from distraction. Why did you feel you had to do that?

  • @sk-7523
    @sk-7523 2 роки тому

    Great video, but why so scary music?

  • @paradigmnnf
    @paradigmnnf Рік тому

    And what is the idea of this background music?

  • @AmanGupta-wb2xh
    @AmanGupta-wb2xh 3 роки тому

    code
    ?

  • @achibaba
    @achibaba 3 роки тому +7

    very bad explanation, waste of time. sorry

  • @TauranusRex
    @TauranusRex 2 роки тому

    The music is way too dramatic :D

  • @TheBeansChopper
    @TheBeansChopper 2 роки тому

    Stop the music, maybe talk instead ... also why stretch the video with unnecessary text

  • @fkeyvan
    @fkeyvan 3 роки тому +1

    Annoying music

  • @gandoreme
    @gandoreme 3 роки тому +7

    very poor selection of music.