glIsEnabled

From OpenGL Reference
Jump to navigation Jump to search

Test whether a capability is enabled.

C Specification[edit]

GLboolean glIsEnabled( GLenum cap );
GLboolean glIsEnabledi( GLenum cap, GLuint index );


Parameters[edit]

cap - Specifies a symbolic constant indicating a GL capability.
index - Specifies the index of the capability.


Description[edit]

 glIsEnabled returns GL_TRUE if cap is an enabled capability and returns GL_FALSE otherwise. Boolean states that are indexed may be tested with glIsEnabledi . For glIsEnabledi , index specifies the index of the capability to test. index must be between zero and the count of indexed capabilities for cap . Initially all capabilities except GL_DITHER are disabled; GL_DITHER is initially enabled.

The following capabilities are accepted for cap :



Constant See
GL_BLEND   glBlendFunc , glLogicOp 
GL_CLIP_DISTANCE i  glEnable 
GL_COLOR_LOGIC_OP   glLogicOp 
GL_CULL_FACE   glCullFace 
GL_DEPTH_CLAMP   glEnable 
GL_DEBUG_OUTPUT   glEnable 
GL_DEBUG_OUTPUT_SYNCHRONOUS   glEnable 
GL_DEPTH_TEST   glDepthFunc , glDepthRange 
GL_DITHER   glEnable 
GL_FRAMEBUFFER_SRGB   glEnable 
GL_LINE_SMOOTH   glLineWidth 
GL_MULTISAMPLE   glSampleCoverage 
GL_POLYGON_SMOOTH   glPolygonMode 
GL_POLYGON_OFFSET_FILL   glPolygonOffset 
GL_POLYGON_OFFSET_LINE   glPolygonOffset 
GL_POLYGON_OFFSET_POINT   glPolygonOffset 
GL_PROGRAM_POINT_SIZE   glEnable 
GL_PRIMITIVE_RESTART   glEnable , glPrimitiveRestartIndex 
GL_SAMPLE_ALPHA_TO_COVERAGE   glSampleCoverage 
GL_SAMPLE_ALPHA_TO_ONE   glSampleCoverage 
GL_SAMPLE_COVERAGE   glSampleCoverage 
GL_SAMPLE_MASK   glEnable 
GL_SCISSOR_TEST   glScissor 
GL_STENCIL_TEST   glStencilFunc , glStencilOp 
GL_TEXTURE_CUBE_MAP_SEAMLESS   glEnable 


Notes[edit]

If an error is generated, glIsEnabled and glIsEnabledi return GL_FALSE .

 GL_DEBUG_OUTPUT and GL_DEBUG_OUTPUT_SYNCHRONOUS are available only if the GL version is 4.3 or greater.


Errors[edit]

 GL_INVALID_ENUM is generated if cap is not an accepted value.

 GL_INVALID_VALUE is generated by glIsEnabledi if index is outside the valid range for the indexed state cap .


Version Support[edit]

 glIsEnabled  2.0+
 glIsEnabledi  3.0+

See Also[edit]

 glEnable , glDisable , glGet 


Copyright[edit]

Copyright© 1991-2006 Silicon Graphics, Inc. Copyright© 2010-2014 Khronos Group. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.