glCullFace specifies whether front- or back-facing facets are culled
(as specified by mode) when facet culling is enabled. Facet
culling is initially disabled.
To enable and disable facet culling, call the
glEnable and glDisable commands
with the argument GL_CULL_FACE .
Facets include triangles,
quadrilaterals,
polygons,
and rectangles.
glFrontFace specifies which of the clockwise and counterclockwise facets
are front-facing and back-facing.
See glFrontFace .