drawing concave polygon using OpenGL ES

OpenGL
1

Hello all,

I am a beginner of ios developer and attempt to draw concave polygon on iPhone using OpenGL ES, after checking document, however, I just found the glu library couldn’t be supported in ios SDK, which contains gluTess* for concave polygon drawing.
Is there any simple solution for this? Or I have to implement my own algorithm for polygon triangulation.
Any suggestion will be helpful, including recommended articles or existing solutions.

Thanks
Lingfei Hu

2

The only polygons you can directly draw with OpenGL ES are triangles. So you will need to triangulate your polygons into triangles.

Have a look at
http://en.wikipedia.org/wiki/Polygon_triangulation and ear clipping for example.