glEdgeFlag — flag edges as either boundary or nonboundary
void glEdgeFlag( | GLboolean | flag) ; |
flag
Specifies the current edge flag value,
either GL_TRUE
or GL_FALSE
. The initial value is GL_TRUE
.
void glEdgeFlagv( | const GLboolean * | flag) ; |
flag
Specifies a pointer to an array that contains a single boolean element, which replaces the current edge flag value.
Each vertex of a polygon,
separate triangle,
or separate quadrilateral specified between a glBegin/glEnd pair
is marked as the start of either a boundary or nonboundary edge.
If the current edge flag is true when the vertex is specified,
the vertex is marked as the start of a boundary edge.
Otherwise, the vertex is marked as the start of a nonboundary edge.
glEdgeFlag
sets the edge flag bit to GL_TRUE
if flag
is GL_TRUE
and to GL_FALSE
otherwise.
The vertices of connected triangles and connected quadrilaterals are always marked as boundary, regardless of the value of the edge flag.
Boundary and nonboundary edge flags on vertices are significant only if
GL_POLYGON_MODE
is set to GL_POINT
or GL_LINE
.
See glPolygonMode.
The current edge flag can be updated at any time.
In particular,
glEdgeFlag
can be called between a call to glBegin and the corresponding
call to glEnd.
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