Blame |
Last modification |
View Log
| RSS feed
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN"
"http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd">
<refentry id="glIsEnabled">
<refmeta>
<refmetainfo>
<copyright>
<year>1991-2006</year>
<holder>Silicon Graphics, Inc.</holder>
</copyright>
</refmetainfo>
<refentrytitle>glIsEnabled</refentrytitle>
<manvolnum>3G</manvolnum>
</refmeta>
<refnamediv>
<refname>glIsEnabled</refname>
<refpurpose>test whether a capability is enabled</refpurpose>
</refnamediv>
<refsynopsisdiv><title>C Specification</title>
<funcsynopsis>
<funcprototype>
<funcdef>GLboolean <function>glIsEnabled</function></funcdef>
<paramdef>GLenum <parameter>cap</parameter></paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
<refsect1 id="parameters"><title>Parameters</title>
<variablelist>
<varlistentry>
<term><parameter>cap</parameter></term>
<listitem>
<para>
Specifies a symbolic constant indicating a GL capability.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1 id="description"><title>Description</title>
<para>
<function>glIsEnabled</function> returns <constant>GL_TRUE</constant> if <parameter>cap</parameter> is an enabled capability
and returns <constant>GL_FALSE</constant> otherwise.
Initially all capabilities except <constant>GL_DITHER</constant> are disabled;
<constant>GL_DITHER</constant> is initially enabled.
</para>
<para>
The following capabilities are accepted for <parameter>cap</parameter>:
</para>
<para>
</para>
<informaltable frame="topbot">
<tgroup cols="2" align="left">
<colspec/>
<colspec/>
<thead>
<row>
<entry rowsep="1" align="left"><emphasis role="bold">
Constant
</emphasis></entry>
<entry rowsep="1" align="left"><emphasis role="bold">
See
</emphasis></entry>
</row>
</thead>
<tbody>
<row>
<entry align="left">
<constant>GL_ALPHA_TEST</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glAlphaFunc</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_AUTO_NORMAL</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glEvalCoord</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_BLEND</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glBlendFunc</refentrytitle></citerefentry>, <citerefentry><refentrytitle>glLogicOp</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_CLIP_PLANE</constant><emphasis>i</emphasis>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glClipPlane</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_COLOR_ARRAY</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glColorPointer</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_COLOR_LOGIC_OP</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glLogicOp</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_COLOR_MATERIAL</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glColorMaterial</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_COLOR_SUM</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glSecondaryColor</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_COLOR_TABLE</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glColorTable</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_CONVOLUTION_1D</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glConvolutionFilter1D</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_CONVOLUTION_2D</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glConvolutionFilter2D</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_CULL_FACE</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glCullFace</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_DEPTH_TEST</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glDepthFunc</refentrytitle></citerefentry>, <citerefentry><refentrytitle>glDepthRange</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_DITHER</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glEnable</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_EDGE_FLAG_ARRAY</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glEdgeFlagPointer</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_FOG</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glFog</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_FOG_COORD_ARRAY</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glFogCoordPointer</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_HISTOGRAM</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glHistogram</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_INDEX_ARRAY</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glIndexPointer</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_INDEX_LOGIC_OP</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glLogicOp</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_LIGHT</constant><emphasis>i</emphasis>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glLightModel</refentrytitle></citerefentry>, <citerefentry><refentrytitle>glLight</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_LIGHTING</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glMaterial</refentrytitle></citerefentry>, <citerefentry><refentrytitle>glLightModel</refentrytitle></citerefentry>, <citerefentry><refentrytitle>glLight</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_LINE_SMOOTH</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glLineWidth</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_LINE_STIPPLE</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glLineStipple</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_MAP1_COLOR_4</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glMap1</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_MAP1_INDEX</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glMap1</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_MAP1_NORMAL</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glMap1</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_MAP1_TEXTURE_COORD_1</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glMap1</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_MAP1_TEXTURE_COORD_2</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glMap1</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_MAP1_TEXTURE_COORD_3</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glMap1</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_MAP1_TEXTURE_COORD_4</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glMap1</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_MAP2_COLOR_4</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glMap2</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_MAP2_INDEX</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glMap2</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_MAP2_NORMAL</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glMap2</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_MAP2_TEXTURE_COORD_1</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glMap2</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_MAP2_TEXTURE_COORD_2</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glMap2</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_MAP2_TEXTURE_COORD_3</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glMap2</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_MAP2_TEXTURE_COORD_4</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glMap2</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_MAP2_VERTEX_3</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glMap2</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_MAP2_VERTEX_4</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glMap2</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_MINMAX</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glMinmax</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_MULTISAMPLE</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glSampleCoverage</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_NORMAL_ARRAY</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glNormalPointer</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_NORMALIZE</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glNormal</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_POINT_SMOOTH</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glPointSize</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_POINT_SPRITE</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glEnable</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_POLYGON_SMOOTH</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glPolygonMode</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_POLYGON_OFFSET_FILL</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glPolygonOffset</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_POLYGON_OFFSET_LINE</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glPolygonOffset</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_POLYGON_OFFSET_POINT</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glPolygonOffset</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_POLYGON_STIPPLE</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glPolygonStipple</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_POST_COLOR_MATRIX_COLOR_TABLE</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glColorTable</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_POST_CONVOLUTION_COLOR_TABLE</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glColorTable</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_RESCALE_NORMAL</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glNormal</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_SAMPLE_ALPHA_TO_COVERAGE</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glSampleCoverage</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_SAMPLE_ALPHA_TO_ONE</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glSampleCoverage</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_SAMPLE_COVERAGE</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glSampleCoverage</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_SCISSOR_TEST</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glScissor</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_SECONDARY_COLOR_ARRAY</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glSecondaryColorPointer</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_SEPARABLE_2D</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glSeparableFilter2D</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_STENCIL_TEST</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glStencilFunc</refentrytitle></citerefentry>, <citerefentry><refentrytitle>glStencilOp</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_TEXTURE_1D</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glTexImage1D</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_TEXTURE_2D</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glTexImage2D</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_TEXTURE_3D</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glTexImage3D</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_TEXTURE_COORD_ARRAY</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glTexCoordPointer</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_TEXTURE_CUBE_MAP</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glTexImage2D</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_TEXTURE_GEN_Q</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glTexGen</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_TEXTURE_GEN_R</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glTexGen</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_TEXTURE_GEN_S</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glTexGen</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_TEXTURE_GEN_T</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glTexGen</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_VERTEX_ARRAY</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glVertexPointer</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_VERTEX_PROGRAM_POINT_SIZE</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glEnable</refentrytitle></citerefentry>
</entry>
</row>
<row>
<entry align="left">
<constant>GL_VERTEX_PROGRAM_TWO_SIDE</constant>
</entry>
<entry align="left">
<citerefentry><refentrytitle>glEnable</refentrytitle></citerefentry>
</entry>
</row>
</tbody>
</tgroup>
</informaltable>
<para>
</para>
</refsect1>
<refsect1 id="notes"><title>Notes</title>
<para>
If an error is generated,
<function>glIsEnabled</function> returns 0.
</para>
<para>
<constant>GL_COLOR_LOGIC_OP</constant>,
<constant>GL_COLOR_ARRAY</constant>,
<constant>GL_EDGE_FLAG_ARRAY</constant>,
<constant>GL_INDEX_ARRAY</constant>,
<constant>GL_INDEX_LOGIC_OP</constant>,
<constant>GL_NORMAL_ARRAY</constant>,
<constant>GL_POLYGON_OFFSET_FILL</constant>,
<constant>GL_POLYGON_OFFSET_LINE</constant>,
<constant>GL_POLYGON_OFFSET_POINT</constant>,
<constant>GL_TEXTURE_COORD_ARRAY</constant>, and
<constant>GL_VERTEX_ARRAY</constant>
are available only
if the GL version is 1.1 or greater.
</para>
<para>
<constant>GL_RESCALE_NORMAL</constant>, and <constant>GL_TEXTURE_3D</constant> are available only if the GL
version is 1.2 or greater.
</para>
<para>
<constant>GL_MULTISAMPLE</constant>,
<constant>GL_SAMPLE_ALPHA_TO_COVERAGE</constant>,
<constant>GL_SAMPLE_ALPHA_TO_ONE</constant>,
<constant>GL_SAMPLE_COVERAGE</constant>,
<constant>GL_TEXTURE_CUBE_MAP</constant>
are available only if the GL version is 1.3 or greater.
</para>
<para>
<constant>GL_FOG_COORD_ARRAY</constant> and <constant>GL_SECONDARY_COLOR_ARRAY</constant>
are available only if the GL version is 1.4 or greater.
</para>
<para>
<constant>GL_POINT_SPRITE</constant>,
<constant>GL_VERTEX_PROGRAM_POINT_SIZE</constant>, and
<constant>GL_VERTEX_PROGRAM_TWO_SIDE</constant>
are available only if the GL version is 2.0 or greater.
</para>
<para>
<constant>GL_COLOR_TABLE</constant>, <constant>GL_CONVOLUTION_1D</constant>, <constant>GL_CONVOLUTION_2D</constant>,
<constant>GL_HISTOGRAM</constant>, <constant>GL_MINMAX</constant>,
<constant>GL_POST_COLOR_MATRIX_COLOR_TABLE</constant>,
<constant>GL_POST_CONVOLUTION_COLOR_TABLE</constant>, and
<constant>GL_SEPARABLE_2D</constant> are available only if <code>ARB_imaging</code> is
returned when <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> is called with <constant>GL_EXTENSIONS</constant>.
</para>
<para>
For OpenGL versions 1.3 and greater, or when the <code>ARB_multitexture</code> extension is supported, the following
parameters return the associated value for the active texture unit:
<constant>GL_TEXTURE_1D</constant>,
<constant>GL_TEXTURE_2D</constant>,
<constant>GL_TEXTURE_3D</constant>,
<constant>GL_TEXTURE_CUBE_MAP</constant>,
<constant>GL_TEXTURE_GEN_S</constant>,
<constant>GL_TEXTURE_GEN_T</constant>,
<constant>GL_TEXTURE_GEN_R</constant>,
<constant>GL_TEXTURE_GEN_Q</constant>,
<constant>GL_TEXTURE_MATRIX</constant>, and
<constant>GL_TEXTURE_STACK_DEPTH</constant>.
Likewise, the following parameters return the associated value for the
active client texture unit:
<constant>GL_TEXTURE_COORD_ARRAY</constant>,
<constant>GL_TEXTURE_COORD_ARRAY_SIZE</constant>,
<constant>GL_TEXTURE_COORD_ARRAY_STRIDE</constant>,
<constant>GL_TEXTURE_COORD_ARRAY_TYPE</constant>.
</para>
</refsect1>
<refsect1 id="errors"><title>Errors</title>
<para>
<constant>GL_INVALID_ENUM</constant> is generated if <parameter>cap</parameter> is not an accepted value.
</para>
<para>
<constant>GL_INVALID_OPERATION</constant> is generated if <function>glIsEnabled</function>
is executed between the execution of <citerefentry><refentrytitle>glBegin</refentrytitle></citerefentry>
and the corresponding execution of <citerefentry><refentrytitle>glEnd</refentrytitle></citerefentry>.
</para>
</refsect1>
<refsect1 id="seealso"><title>See Also</title>
<para>
<citerefentry><refentrytitle>glEnable</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glEnableClientState</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glGet</refentrytitle></citerefentry>
</para>
</refsect1>
<refsect1 id="Copyright"><title>Copyright</title>
<para>
Copyright <trademark class="copyright"></trademark> 1991-2006
Silicon Graphics, Inc. This document is licensed under the SGI
Free Software B License. For details, see
<ulink url="http://oss.sgi.com/projects/FreeB/">http://oss.sgi.com/projects/FreeB/</ulink>.
</para>
</refsect1>
</refentry>