GL_POLYGON working strangely

Question

On the right is the shape generated by GL_LINE_STRIP and on the left is it generated by GL_POLYGON.

There's a function which generates each point 1 by 1 in order.

Why is there such a big difference in the basic shape? Notice how less 'curved' each portion of the cloud is in the GL_POLYGON version.

Any clue how to fix this? Or maybe use something else to fill this polygon I have?

fairly impressive it drew the way it did, it's still concave somehow! — peter karasev, Jun 07 '17 at 19:45

score 2 · Accepted Answer · edited May 23 '17 at 10:30

2

GL_POLYGON: Draws a single, convex polygon. Vertices 1 through N define this polygon.

You'll have to triangulate your polygon and use GL_TRIANGLES instead.

edited May 23 '17 at 10:30

Community

answered Oct 03 '13 at 20:09

genpfault

Jean-Simon Brochu · Answer 2 · 2013-10-04T17:26:51.167

0

Or you could "shade" the fragments inside of the polygon. Just like a polygon filling algorithm

edited Oct 04 '13 at 17:26

answered Oct 04 '13 at 13:46

Jean-Simon Brochu

2 Answers2