glEdgeFlag

NAME

glEdgeFlag, glEdgeFlagv - flag edges as either boundary or non-boundary

C SPECIFICATION

void glEdgeFlag(GLboolean flag)

PARAMETERS

flag Specifies the current edge flag value, either GL_TRUE or GL_FALSE. The initial value is GL_TRUE.

C SPECIFICATION

void glEdgeFlagv(const GLboolean *flag)

PARAMETERS

flag Specifies a pointer to an array that contains a single Boolean element, which replaces the current edge flag value.

DESCRIPTION

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 non-boundary 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 non-boundary 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 non-boundary edge flags on vertices are significant only if GL_POLYGON_MODE is set to GL_POINT or GL_LINE. See glPolygonMode.

NOTES

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.

ASSOCIATED GETS

glGet with argument GL_EDGE_FLAG

SEE ALSO

glBegin, glEdgeFlagPointer, glPolygonMode