In case of polygon from points, tolerances have no effect.
These settings are used when curves or spheres are faceted.
Pass 0, 0, 0, 3 to get triangulated mesh element from your shape element.
As input use descriptor made using mdlElmdscr_createFromVertices with 'closed' parameter set to TRUE.
Example:
MSElementDescrP poylgElm;
MSElementDescrP meshElm;
if (
SUCCESS == mdlElmdscr_createFromVertices(&polygElm, NULL, points, num_points, TRUE, FALSE)
&&
SUCCESS == mdlMeshDscr_fromElmdscr(&meshElm, polygElem, MASTERFILE, 0,0,0,3,FALSE)
)
{
// use mesh element
mdlElmdscr_freeAll(&polygElm);
mdlElmdscr_freeAll(&meshElm);
}