'\" et  
'\"macro stdmacro
.ds Vn Version 1.2
.ds Dt 24 September 1999
.ds Re Release 1.2.1
.ds Dp May 22 14:45
.ds Dm 9 May 22 14:
.ds Xs 14538     7
.TH GLISENABLED 3G
.SH NAME
.B "glIsEnabled
\- test whether a capability is enabled

.SH C SPECIFICATION
GLboolean \f3glIsEnabled\fP(
GLenum \fIcap\fP )
.nf
.fi

.SH PARAMETERS
.TP \w'\f2cap\fP\ \ 'u 
\f2cap\fP
Specifies a symbolic constant indicating a GL capability.
.SH DESCRIPTION
\%\f3glIsEnabled\fP returns \%\f3GL_TRUE\fP if \f2cap\fP is an enabled capability
and returns \%\f3GL_FALSE\fP otherwise.
Initially all capabilities except \%\f3GL_DITHER\fP are disabled;
\%\f3GL_DITHER\fP is initially enabled.
.P
The following capabilities are accepted for \f2cap\fP:
.P

.Bd -literal
 \%\f3GL_ALPHA_TEST\fP          \%\f3glAlphaFunc\fP
 \%\f3GL_AUTO_NORMAL\fP         \%\f3glEvalCoord\fP
 \%\f3GL_BLEND\fP               \%\f3glBlendFunc\fP, \%\f3glLogicOp\fP
 \%\f3GL_CLIP_PLANE\fP\f2i\fP         \%\f3glClipPlane\fP
 \%\f3GL_COLOR_ARRAY\fP         \%\f3glColorPointer\fP
 \%\f3GL_COLOR_LOGIC_OP\fP      \%\f3glLogicOp\fP
 \%\f3GL_COLOR_MATERIAL\fP      \%\f3glColorMaterial\fP
 \%\f3GL_COLOR_TABLE\fP         \%\f3glColorTable\fP
 \%\f3GL_CONVOLUTION_1D\fP      \%\f3glConvolutionFilter1D\fP
 \%\f3GL_CONVOLUTION_2D\fP      \%\f3glConvolutionFilter2D\fP
 \%\f3GL_CULL_FACE\fP           \%\f3glCullFace\fP
 \%\f3GL_DEPTH_TEST\fP          \%\f3glDepthFunc\fP, \%\f3glDepthRange\fP
 \%\f3GL_DITHER\fP              \%\f3glEnable\fP
 \%\f3GL_EDGE_FLAG_ARRAY\fP     \%\f3glEdgeFlagPointer\fP
 \%\f3GL_FOG\fP                 \%\f3glFog\fP
 \%\f3GL_HISTOGRAM\fP           \%\f3glHistogram\fP
 \%\f3GL_INDEX_ARRAY\fP         \%\f3glIndexPointer\fP
 \%\f3GL_INDEX_LOGIC_OP\fP         \%\f3glLogicOp\fP
 \%\f3GL_LIGHT\fP\f2i\fP        \%\f3glLightModel\fP, \%\f3glLight\fP
 \%\f3GL_LIGHTING\fP            \%\f3glMaterial\fP, \%\f3glLightModel\fP, \%\f3glLight\fP
 \%\f3GL_LINE_SMOOTH\fP         \%\f3glLineWidth\fP
 \%\f3GL_LINE_STIPPLE\fP        \%\f3glLineStipple\fP
 \%\f3GL_MAP1_COLOR_4\fP        \%\f3glMap1\fP
 \%\f3GL_MAP1_INDEX\fP          \%\f3glMap1\fP
 \%\f3GL_MAP1_NORMAL\fP         \%\f3glMap1\fP
 \%\f3GL_MAP1_TEXTURE_COORD_1\fP    \%\f3glMap1\fP
 \%\f3GL_MAP1_TEXTURE_COORD_2\fP    \%\f3glMap1\fP
 \%\f3GL_MAP1_TEXTURE_COORD_3\fP    \%\f3glMap1\fP
 \%\f3GL_MAP1_TEXTURE_COORD_4\fP    \%\f3glMap1\fP
 \%\f3GL_MAP2_COLOR_4\fP        \%\f3glMap2\fP
 \%\f3GL_MAP2_INDEX\fP          \%\f3glMap2\fP
 \%\f3GL_MAP2_NORMAL\fP         \%\f3glMap2\fP
 \%\f3GL_MAP2_TEXTURE_COORD_1\fP    \%\f3glMap2\fP
 \%\f3GL_MAP2_TEXTURE_COORD_2\fP    \%\f3glMap2\fP
 \%\f3GL_MAP2_TEXTURE_COORD_3\fP    \%\f3glMap2\fP
 \%\f3GL_MAP2_TEXTURE_COORD_4\fP    \%\f3glMap2\fP
 \%\f3GL_MAP2_VERTEX_3\fP       \%\f3glMap2\fP
 \%\f3GL_MAP2_VERTEX_4\fP       \%\f3glMap2\fP
 \%\f3GL_MINMAX\fP              \%\f3glMinmax\fP
 \%\f3GL_NORMAL_ARRAY\fP           \%\f3glNormalPointer\fP
 \%\f3GL_NORMALIZE\fP           %\f3glNormal\fP
 \%\f3GL_POINT_SMOOTH\fP        \%\f3glPointSize\fP
 \%\f3GL_POLYGON_SMOOTH\fP      \%\f3glPolygonMode\fP
 \%\f3GL_POLYGON_OFFSET_FILL\fP     \%\f3glPolygonOffset\fP
 \%\f3GL_POLYGON_OFFSET_LINE\fP     \%\f3glPolygonOffset\fP
 \%\f3GL_POLYGON_OFFSET_POINT\fP    \%\f3glPolygonOffset\fP
 \%\f3GL_POLYGON_STIPPLE\fP     \%\f3glPolygonStipple\fP
 \%\f3GL_POST_COLOR_MATRIX_COLOR_TABLE\fP   \%\f3glColorTable\fP
 \%\f3GL_POST_CONVOLUTION_COLOR_TABLE\fP    \%\f3glColorTable\fP
 \%\f3GL_RESCALE_NORMAL\fP          \%\f3glNormal\fP
 \%\f3GL_SCISSOR_TEST\fP            \%\f3glScissor\fP
 \%\f3GL_SEPARABLE_2D\fP            \%\f3glSeparableFilter2D\fP
 \%\f3GL_STENCIL_TEST\fP            \%\f3glStencilFunc\fP, \%\f3glStencilOp\fP
 \%\f3GL_TEXTURE_1D\fP              \%\f3glTexImage1D\fP
 \%\f3GL_TEXTURE_2D\fP              \%\f3glTexImage2D\fP
 \%\f3GL_TEXTURE_3D\fP              \%\f3glTexImage3D\fP
 \%\f3GL_TEXTURE_COORD_ARRAY\fP     \%\f3glTexCoordPointer\fP
 \%\f3GL_TEXTURE_GEN_Q\fP           \%\f3glTexGen\fP
 \%\f3GL_TEXTURE_GEN_R\fP           \%\f3glTexGen\fP
 \%\f3GL_TEXTURE_GEN_S\fP           \%\f3glTexGen\fP
 \%\f3GL_TEXTURE_GEN_T\fP           \%\f3glTexGen\fP
 \%\f3GL_VERTEX_ARRAY\fP            \%\f3glVertexPointer\fP
.Ed

.SH NOTES
If an error is generated,
\%\f3glIsEnabled\fP returns 0.
.P
\%\f3GL_COLOR_LOGIC_OP\fP, 
\%\f3GL_COLOR_ARRAY\fP,
\%\f3GL_EDGE_FLAG_ARRAY\fP,
\%\f3GL_INDEX_ARRAY\fP,
\%\f3GL_INDEX_LOGIC_OP\fP,
\%\f3GL_NORMAL_ARRAY\fP,
\%\f3GL_POLYGON_OFFSET_FILL\fP,  
\%\f3GL_POLYGON_OFFSET_LINE\fP,
\%\f3GL_POLYGON_OFFSET_POINT\fP,
\%\f3GL_TEXTURE_COORD_ARRAY\fP, and
\%\f3GL_VERTEX_ARRAY\fP
are available only
if the GL version is 1.1 or greater
.P
\%\f3GL_RESCALE_NORMAL\fP, and \%\f3GL_TEXTURE_3D\fP are available only if the GL
version is 1.2 or greater.
.P
\%\f3GL_COLOR_TABLE\fP, \%\f3GL_CONVOLUTION_1D\fP, \%\f3GL_CONVOLUTION_2D\fP,
\%\f3GL_HISTOGRAM\fP, \%\f3GL_MINMAX\fP,
\%\f3GL_POST_COLOR_MATRIX_COLOR_TABLE\fP,
\%\f3GL_POST_CONVOLUTION_COLOR_TABLE\fP, and
\%\f3GL_SEPARABLE_2D\fP are available only if \%\f3GL_ARB_imaging\fP is
returned when \%\f3glGet\fP is called with \%\f3GL_EXTENSIONS\fP.
.P
When the \%\f3GL_ARB_multitexture\fP extension is supported, the following
parameters return the associated value for the active texture unit.
\%\f3GL_TEXTURE_1D\fP, \%\f3GL_TEXTURE_BINDING_1D\fP,
\%\f3GL_TEXTURE_2D\fP, \%\f3GL_TEXTURE_BINDING_2D\fP,
\%\f3GL_TEXTURE_3D\fP, \%\f3GL_TEXTURE_BINDING_3D\fP,
\%\f3GL_TEXTURE_GEN_S\fP,
\%\f3GL_TEXTURE_GEN_T\fP,
\%\f3GL_TEXTURE_GEN_R\fP,
\%\f3GL_TEXTURE_GEN_Q\fP,
\%\f3GL_TEXTURE_MATRIX\fP, and
\%\f3GL_TEXTURE_STACK_DEPTH\fP.
Likewise, the following parameters return the associated value for the
active client texture unit:
\%\f3GL_TEXTURE_COORD_ARRAY\fP,
\%\f3GL_TEXTURE_COORD_ARRAY_SIZE\fP,
\%\f3GL_TEXTURE_COORD_ARRAY_STRIDE\fP,
\%\f3GL_TEXTURE_COORD_ARRAY_TYPE\fP.
.SH ERRORS
\%\f3GL_INVALID_ENUM\fP is generated if \f2cap\fP is not an accepted value.
.P
\%\f3GL_INVALID_OPERATION\fP is generated if \%\f3glIsEnabled\fP
is executed between the execution of \%\f3glBegin\fP
and the corresponding execution of \%\f3glEnd\fP.
.SH SEE ALSO
\%\f3glEnable\fP,
\%\f3glEnableClientState\fP,
\%\f3glGet\fP