glEdgeFlag function

Flags edges as either boundary or nonboundary.

Syntax

void WINAPI glEdgeFlag(
   GLboolean flag
);

Parameters

flag

Specifies the current edge flag value, either TRUE or FALSE.

Return value

This function does not return a value.

Remarks

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. If the current edge flag is FALSE, the vertex is marked as the start of a nonboundary edge. The glEdgeFlag function sets the edge flag to TRUE if flag is nonzero, 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.

Initially, the edge flag bit is TRUE.

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.

The following functions retrieve information related to glEdgeFlag:

glGet with argument GL_EDGE_FLAG

Requirements

Requirement	Value
Minimum supported client	Windows 2000 Professional [desktop apps only]
Minimum supported server	Windows 2000 Server [desktop apps only]
Header	Gl.h
Library	Opengl32.lib
DLL	Opengl32.dll