1 <?xml version=
"1.0" encoding=
"UTF-8"?>
2 <!DOCTYPE book PUBLIC
"-//OASIS//DTD DocBook MathML Module V1.1b1//EN"
3 "http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd">
4 <refentry id=
"glEdgeFlag">
9 <holder>Silicon Graphics, Inc.
</holder>
12 <refentrytitle>glEdgeFlag
</refentrytitle>
13 <manvolnum>3G
</manvolnum>
16 <refname>glEdgeFlag
</refname>
17 <refpurpose>flag edges as either boundary or nonboundary
</refpurpose>
19 <refsynopsisdiv><title>C Specification
</title>
22 <funcdef>void
<function>glEdgeFlag
</function></funcdef>
23 <paramdef>GLboolean
<parameter>flag
</parameter></paramdef>
27 <refsect1 id=
"parameters"><title>Parameters
</title>
30 <term><parameter>flag
</parameter></term>
33 Specifies the current edge flag value,
34 either
<constant>GL_TRUE
</constant> or
<constant>GL_FALSE
</constant>. The initial value is
<constant>GL_TRUE
</constant>.
40 <refsynopsisdiv><title>C Specification
</title>
43 <funcdef>void
<function>glEdgeFlagv
</function></funcdef>
44 <paramdef>const GLboolean *
<parameter>flag
</parameter></paramdef>
48 <refsect1 id=
"parameters2"><title>Parameters
</title>
51 <term><parameter>flag
</parameter></term>
54 Specifies a pointer to an array that contains a single boolean element,
55 which replaces the current edge flag value.
61 <refsect1 id=
"description"><title>Description
</title>
63 Each vertex of a polygon,
65 or separate quadrilateral specified between a
<citerefentry><refentrytitle>glBegin
</refentrytitle></citerefentry>/
<citerefentry><refentrytitle>glEnd
</refentrytitle></citerefentry> pair
66 is marked as the start of either a boundary or nonboundary edge.
67 If the current edge flag is true when the vertex is specified,
68 the vertex is marked as the start of a boundary edge.
69 Otherwise, the vertex is marked as the start of a nonboundary edge.
70 <function>glEdgeFlag
</function> sets the edge flag bit to
<constant>GL_TRUE
</constant> if
<parameter>flag
</parameter> is
<constant>GL_TRUE
</constant>
71 and to
<constant>GL_FALSE
</constant> otherwise.
74 The vertices of connected triangles and connected quadrilaterals are always
76 regardless of the value of the edge flag.
79 Boundary and nonboundary edge flags on vertices are significant only if
80 <constant>GL_POLYGON_MODE
</constant> is set to
<constant>GL_POINT
</constant> or
<constant>GL_LINE
</constant>.
81 See
<citerefentry><refentrytitle>glPolygonMode
</refentrytitle></citerefentry>.
84 <refsect1 id=
"notes"><title>Notes
</title>
86 The current edge flag can be updated at any time.
88 <function>glEdgeFlag
</function> can be called between a call to
<citerefentry><refentrytitle>glBegin
</refentrytitle></citerefentry> and the corresponding
89 call to
<citerefentry><refentrytitle>glEnd
</refentrytitle></citerefentry>.
92 <refsect1 id=
"associatedgets"><title>Associated Gets
</title>
94 <citerefentry><refentrytitle>glGet
</refentrytitle></citerefentry> with argument
<constant>GL_EDGE_FLAG
</constant>
97 <refsect1 id=
"seealso"><title>See Also
</title>
99 <citerefentry><refentrytitle>glBegin
</refentrytitle></citerefentry>,
100 <function>glEdgeFlagPointer
</function>,
101 <citerefentry><refentrytitle>glPolygonMode
</refentrytitle></citerefentry>
104 <refsect1 id=
"Copyright"><title>Copyright
</title>
106 Copyright
<trademark class=
"copyright"></trademark> 1991-
2006
107 Silicon Graphics, Inc. This document is licensed under the SGI
108 Free Software B License. For details, see
109 <ulink url=
"http://oss.sgi.com/projects/FreeB/">http://oss.sgi.com/projects/FreeB/
</ulink>.