Click here to Skip to main content
13,354,132 members (55,980 online)
Click here to Skip to main content
Add your own
alternative version


23 bookmarked
Posted 6 Feb 2002

Tesselation of Mono Connected Non Convex Polygon

, 6 Feb 2002
Rate this:
Please Sign up or sign in to vote.
Tesselation of mono connected non convex polygon

Sample Image - PolyTry.jpg


A simple alternative to OpenGL polygon tesselation callback. You can focus on file triangle.h that contain the class to evaluate convexity of polygon and tesselate the polygon. No extra points are inserted. You can work only with planar polygon also in 3D.

Every suggestion in order to speed up the class and create better tesselation ('better' triangles) is appreciated.


  • 6th February, 2002: Initial post


This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)


About the Author

Peppino Sbargzeguti
United States United States
No Biography provided

You may also be interested in...

Comments and Discussions

Generalcut object in slicing Pin
joy_nim24-Feb-06 7:01
memberjoy_nim24-Feb-06 7:01 
GeneralPossible error and fix Pin
GregDude21-Jul-05 16:34
memberGregDude21-Jul-05 16:34 
GeneralRobust tesselation Pin
Skavenger1-Jul-05 23:04
memberSkavenger1-Jul-05 23:04 
GeneralRe: Robust tesselation [modified] Pin
Liu Guoping9-Aug-06 16:51
memberLiu Guoping9-Aug-06 16:51 
AnswerRe: Robust tesselation Pin
Skavenger310-Aug-06 2:42
memberSkavenger310-Aug-06 2:42 
GeneralProblem in CPolyTri::ComputeNormal Pin
Torsten B8-Jun-04 2:43
memberTorsten B8-Jun-04 2:43 
GeneralRe: Problem in CPolyTri::ComputeNormal Pin
Sebastien Maraux13-Dec-04 4:52
memberSebastien Maraux13-Dec-04 4:52 
GeneralRe: Problem in CPolyTri::ComputeNormal Pin
Sébastien Maraux14-Dec-04 0:45
memberSébastien Maraux14-Dec-04 0:45 
GeneralGood Article Pin
mchapman123422-May-04 12:50
membermchapman123422-May-04 12:50 
GeneralFound an index range error in code Pin
TruePyroman23-Feb-03 15:38
memberTruePyroman23-Feb-03 15:38 
GeneralRe: Found an index range error in code Pin
topus10-Apr-03 3:46
membertopus10-Apr-03 3:46 
GeneralBetter tesselation Pin
jeckle8-Feb-02 10:00
memberjeckle8-Feb-02 10:00 
GeneralRe: Better tesselation Pin
pepito10-Feb-02 23:05
memberpepito10-Feb-02 23:05 
A more little explanation about my article. In order to tesselate the polygon i use this tecnique:
First compute the normal of polygon (i use the newell method see Graphic Gems..)
For each sequence of three vertex ( i, j, k ) in the polygon compute the vector area (alias normal of triangle).
If the normal go in the opposite direction of polygon normal the triangle is 'concave' and go ahead.
If the area il 0.0 the point j is alligned from i to k and eliminated from the list of vertex.
If the normal of triangle is in the same direction of polygon normal the triangle is convex. In the last case check if any other point is inside the triangle (the IsPointInside function). This function test if the point is on solid angle ik ^ jk. if this is true compute distance of intersection k->point to line ij and test distance. If all is good emit triangle, remove vertex j from list and go to the next triplet....
The reason for wich i posted this article is that i don't find this tecnique in any book or article and ave a doubt about the mathematical basic of my algoritm In other words is true that it work in any case ? (my experience ask yes but is very far from a theorem...)
The Delauney algortim work fine but is 'computational' more expensive than my algortim (using my Delauney implementation) for this reason i try this way. At the end my apologize for my poor english but my sincerly idea is to contribute to codeproject and suggest a way to resolv a problem that i found. Thanks pepito.
GeneralRe: Better tesselation Pin
jeckle11-Feb-02 11:46
memberjeckle11-Feb-02 11:46 
GeneralRe: Better tesselation Pin
Rick York11-Feb-02 11:53
memberRick York11-Feb-02 11:53 
GeneralBetter tesselation Pin
Tim Aidley8-Feb-02 3:45
memberTim Aidley8-Feb-02 3:45 
GeneralRe: Better tesselation Pin
kilowatt8-Feb-02 9:21
memberkilowatt8-Feb-02 9:21 
GeneralRe: Better tesselation Pin
pepito sbarzeguti10-Feb-02 23:03
memberpepito sbarzeguti10-Feb-02 23:03 
QuestionGuareschiano anche tu? Pin
Anonymous7-Feb-02 22:19
memberAnonymous7-Feb-02 22:19 
AnswerRe: Guareschiano anche tu? Pin
Dieter Hammer8-Feb-02 1:04
memberDieter Hammer8-Feb-02 1:04 
GeneralRe: Guareschiano anche tu? Pin
pepito8-Feb-02 2:38
memberpepito8-Feb-02 2:38 
GeneralRe: Guareschiano anche tu? Pin
Anonymous10-Feb-02 23:37
memberAnonymous10-Feb-02 23:37 
GeneralVery poor article on very interesting subject... Pin
George7-Feb-02 15:25
memberGeorge7-Feb-02 15:25 
GeneralRe: Very poor article on very interesting subject... Pin
Pepito Sbarzeguti7-Feb-02 22:46
memberPepito Sbarzeguti7-Feb-02 22:46 
GeneralRe: Very poor article on very interesting subject... Pin
Anonymous7-Feb-02 22:47
memberAnonymous7-Feb-02 22:47 

General General    News News    Suggestion Suggestion    Question Question    Bug Bug    Answer Answer    Joke Joke    Praise Praise    Rant Rant    Admin Admin   

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.

Permalink | Advertise | Privacy | Terms of Use | Mobile
Web03 | 2.8.180111.1 | Last Updated 7 Feb 2002
Article Copyright 2002 by Peppino Sbargzeguti
Everything else Copyright © CodeProject, 1999-2018
Layout: fixed | fluid