convert a convex path to triangle list - c++

Question

What is the best way to convert a convex path (it is describing in points set) to a list of triangles to be used in opengl render. I think the best stuff is sample code or demo :) thanks!

Answer 1

It sounds like you are looking for one of the many "convert a polygon to a series of triangles" solutions:
Maybe something in one of these will help:
Ear Clipping
List item
poly2tri (with source code)
If you are trying to understand the concepts, the first two are a good place to start.
If you need an implementation, start with the third.
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Answer 2

If your polygon is really convex and not concave you can just draw it as a triangle fan. That is guaranteed to work.
Here is a alternative recursive algorithm that I wrote a few years ago. It also triangulates a concave polygon and on average generates a much nicer triangulation (e.g. less sliver polygons):
void ConcaveTesselator (unsigned a_NumVertices)
{
unsigned left[32]; // enough space for 2^32 recursions:
unsigned right[32];
unsigned stacktop = 0;
// prepare stack:
left[0] = 0;
right[0] = a_NumVertices-1;
stacktop = 1;
while (stacktop)
{
unsigned l,r,m;
// pop current interval from the stack and subdivide:
stacktop--;
l = left[stacktop];
r = right[stacktop];
m = (l+r)>>1;
// replace this with your triangle drawing function
// or store the indices l,m,r and draw the triangles
// as a triangle list later:
DrawTriangleWithIndices (l,m,r);
// recursive subdivide:
if (m-l > 1)
{
left[stacktop] = l;
right[stacktop] = m;
stacktop++;
}
if (r-m > 1)
{
left[stacktop] = m;
right[stacktop] = r;
stacktop++;
}
}
}