Tests whether a capability is enabled.
OpenGL C bindings library: libGL.a
GLboolean glIsEnabled (GLenum Capability)
| Capability | Specifies a symbolic constant indicating a GL capability. |
The glIsEnabled subroutine returns GL_TRUE if the Capability parameter is an enabled capability and returns GL_FALSE otherwise. The following capabilities are accepted for Capability:
| GL_ALPHA_TEST | See glAlphaFunc. |
| GL_AUTO_NORMAL | See glEvalCoord. |
| GL_BLEND | See glBlendFunc. |
| GL_CLIP_PLANEi | See glClipPlane. |
| GL_COLOR_ARRAY | See glColorPointer |
| GL_COLOR_ARRAY_EXT | See glColorPointerEXT |
| GL_COLOR_LOGIC_OP | See glLogicOp. |
| GL_COLOR_MATERIAL | See glColorMaterial. |
| GL_CULL_FACE | See glCullFace. |
| GL_CULL_VERTEX_IBM | See GL_CULL_VERTEX_IBM. |
| GL_DEPTH_TEST | See glDepthFunc and glDepthRange. |
| GL_DITHER | See glEnable. |
| GL_EDGE_FLAG_ARRAY | See glEdgeFlagPointer. |
| GL_EDGE_FLAG_ARRAY_EXT | See glEdgeFlagPointerEXT |
| GL_FOG | See glFog. |
| GL_INDEX_ARRAY | See glIndexPointer. |
| GL_INDEX_ARRAY_EXT | See glIndexPointerEXT |
| GL_LIGHTi | See glLightModel and glLight. |
| GL_LIGHTING | See glMaterial, glLightModel, and glLight. |
| GL_LINE_SMOOTH | See glLineWidth. |
| GL_LINE_STIPPLE | See glLineStipple. |
| GL_LOGIC_OP | See glLogicOp. |
| GL_MAP1_COLOR_4 | See glMap1. |
| GL_MAP1_INDEX | See glMap1. |
| GL_MAP1_NORMAL | See glMap1. |
| GL_MAP1_TEXTURE_COORD_1 | See glMap1. |
| GL_MAP1_TEXTURE_COORD_2 | See glMap1. |
| GL_MAP1_TEXTURE_COORD_3 | See glMap1. |
| GL_MAP1_TEXTURE_COORD_4 | See glMap1. |
| GL_MAP1_VERTEX_3 | See glMap1. |
| GL_MAP1_VERTEX_4 | See glMap1. |
| GL_MAP2_COLOR_4 | See glMap2. |
| GL_MAP2_INDEX | See glMap2. |
| GL_MAP2_NORMAL | See glMap2. |
| GL_MAP2_TEXTURE_COORD_1 | See glMap2. |
| GL_MAP2_TEXTURE_COORD_2 | See glMap2. |
| GL_MAP2_TEXTURE_COORD_3 | See glMap2. |
| GL_MAP2_TEXTURE_COORD_4 | See glMap2. |
| GL_MAP2_VERTEX_3 | See glMap2. |
| GL_MAP2_VERTEX_4 | See glMap2. |
| GL_NORMAL_ARRAY | See glNormalPointer. |
| GL_NORMAL_ARRAY_EXT | See glNormalPointerEXT |
| GL_NORMALIZE | See glNormal. |
| GL_POINT_SMOOTH | See glPointSize. |
| GL_POLYGON_SMOOTH | See glPolygonMode. |
| GL_POLYGON_STIPPLE | See glPolygonStipple. |
| GL_POLYGON_OFFSET_EXT | See glPolygonOffsetEXT |
| GL_POLYGON_OFFSET_FILL | See glPolygonOffset. |
| GL_POLYGON_OFFSET_LINE | See glPolygonOffset. |
| GL_POLYGON_OFFSET_POINT | See glPolygonOffset. |
| GL_RESCALE_NORMAL_EXT | If normal rescaling is enabled, a new operation is added to the transformation of the normal vector into eye coordinates. The normal vector is rescaled after it is multiplied by the inverse modelview matrix and before it is normalized. |
| GL_SCISSOR_TEST | See glScissor. |
| GL_STENCIL_TEST | See glStencilFunc and glStencilOp. |
| GL_TEXTURE_1D | See glTexImage1D. |
| GL_TEXTURE_2D | See glTexImage2D. |
| GL_TEXTURE_3D_EXT | See glTexImage3DEXT |
| GL_TEXTURE_COORD_ARRAY | See glTexCoordPointer. |
| GL_VERTEX_ARRAY | See glVertexPointer. |
| GL_TEXTURE_COORD_ARRAY_EXT | See glTexCoordPointerEXT |
| GL_TEXTURE_GEN_Q | See glTexGen. |
| GL_TEXTURE_GEN_R | See glTexGen. |
| GL_TEXTURE_GEN_S | See glTexGen. |
| GL_TEXTURE_GEN_T | See glTexGen. |
| GL_VERTEX_ARRAY_EXT | See glVertexPointerEXT. |
If an error is generated, glIsEnabled returns 0 (zero).
| GL_INVALID_ENUM | Capability is not an accepted value. |
| GL_INVALID_OPERATION | The glIsEnabled subroutine is called between a call to glBegin and the corresponding call to glEnd. |
| /usr/include/GL/gl.h | Contains C language constants, variable type definitions, and ANSI function prototypes for OpenGL. |
The glBegin or glEnd subroutine, glEnable subroutine.