glEnable(3g)

1GLENABLE(3G)                     OpenGL Manual                    GLENABLE(3G)
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NAME

6       glEnable - enable or disable server-side GL capabilities
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C SPECIFICATION

9       void glEnable(GLenum cap);
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PARAMETERS

12       cap
13           Specifies a symbolic constant indicating a GL capability.
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C SPECIFICATION

16       void glDisable(GLenum cap);
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PARAMETERS

19       cap
20           Specifies a symbolic constant indicating a GL capability.
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C SPECIFICATION

23       void glEnablei(GLenum cap, GLuint index);
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PARAMETERS

26       cap
27           Specifies a symbolic constant indicating a GL capability.
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29       index
30           Specifies the index of the swtich to enable.
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C SPECIFICATION

33       void glDisablei(GLenum cap, GLuint index);
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PARAMETERS

36       cap
37           Specifies a symbolic constant indicating a GL capability.
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39       index
40           Specifies the index of the swtich to disable.
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DESCRIPTION

43       glEnable and glDisable() enable and disable various capabilities. Use
44       glIsEnabled() or glGet() to determine the current setting of any
45       capability. The initial value for each capability with the exception of
46       GL_DITHER and GL_MULTISAMPLE is GL_FALSE. The initial value for
47       GL_DITHER and GL_MULTISAMPLE is GL_TRUE.
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49       Both glEnable and glDisable() take a single argument, cap, which can
50       assume one of the following values:
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52       Some of the GL's capabilities are indexed.  glEnablei and glDisablei
53       enable and disable indexed capabilities.
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55       GL_BLEND
56
57           If enabled, blend the computed fragment color values with the
58           values in the color buffers. See glBlendFunc().
59
60       GL_CLIP_DISTANCEi
61
62           If enabled, clip geometry against user-defined half space i.
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64       GL_COLOR_LOGIC_OP
65
66           If enabled, apply the currently selected logical operation to the
67           computed fragment color and color buffer values. See glLogicOp().
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69       GL_CULL_FACE
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71           If enabled, cull polygons based on their winding in window
72           coordinates. See glCullFace().
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74       GL_DEBUG_OUTPUT
75
76           If enabled, debug messages are produced by a debug context. When
77           disabled, the debug message log is silenced. Note that in a
78           non-debug context, very few, if any messages might be produced,
79           even when GL_DEBUG_OUTPUT is enabled.
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81       GL_DEBUG_OUTPUT_SYNCHRONOUS
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83           If enabled, debug messages are produced synchronously by a debug
84           context. If disabled, debug messages may be produced
85           asynchronously. In particular, they may be delayed relative to the
86           execution of GL commands, and the debug callback function may be
87           called from a thread other than that in which the commands are
88           executed. See glDebugMessageCallback().
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90       GL_DEPTH_CLAMP
91
92           If enabled, the -wc≤zc≤wc plane equation is ignored by view volume
93           clipping (effectively, there is no near or far plane clipping). See
94           glDepthRange().
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96       GL_DEPTH_TEST
97
98           If enabled, do depth comparisons and update the depth buffer. Note
99           that even if the depth buffer exists and the depth mask is
100           non-zero, the depth buffer is not updated if the depth test is
101           disabled. See glDepthFunc() and glDepthRange().
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103       GL_DITHER
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105           If enabled, dither color components or indices before they are
106           written to the color buffer.
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108       GL_FRAMEBUFFER_SRGB
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110           If enabled and the value of
111           GL_FRAMEBUFFER_ATTACHMENT_COLOR_ENCODING for the framebuffer
112           attachment corresponding to the destination buffer is GL_SRGB, the
113           R, G, and B destination color values (after conversion from
114           fixed-point to floating-point) are considered to be encoded for the
115           sRGB color space and hence are linearized prior to their use in
116           blending.
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118       GL_LINE_SMOOTH
119
120           If enabled, draw lines with correct filtering. Otherwise, draw
121           aliased lines. See glLineWidth().
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123       GL_MULTISAMPLE
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125           If enabled, use multiple fragment samples in computing the final
126           color of a pixel. See glSampleCoverage().
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128       GL_POLYGON_OFFSET_FILL
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130           If enabled, and if the polygon is rendered in GL_FILL mode, an
131           offset is added to depth values of a polygon's fragments before the
132           depth comparison is performed. See glPolygonOffset().
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134       GL_POLYGON_OFFSET_LINE
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136           If enabled, and if the polygon is rendered in GL_LINE mode, an
137           offset is added to depth values of a polygon's fragments before the
138           depth comparison is performed. See glPolygonOffset().
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140       GL_POLYGON_OFFSET_POINT
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142           If enabled, an offset is added to depth values of a polygon's
143           fragments before the depth comparison is performed, if the polygon
144           is rendered in GL_POINT mode. See glPolygonOffset().
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146       GL_POLYGON_SMOOTH
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148           If enabled, draw polygons with proper filtering. Otherwise, draw
149           aliased polygons. For correct antialiased polygons, an alpha buffer
150           is needed and the polygons must be sorted front to back.
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152       GL_PRIMITIVE_RESTART
153
154           Enables primitive restarting. If enabled, any one of the draw
155           commands which transfers a set of generic attribute array elements
156           to the GL will restart the primitive when the index of the vertex
157           is equal to the primitive restart index. See
158           glPrimitiveRestartIndex().
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160       GL_PRIMITIVE_RESTART_FIXED_INDEX
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162           Enables primitive restarting with a fixed index. If enabled, any
163           one of the draw commands which transfers a set of generic attribute
164           array elements to the GL will restart the primitive when the index
165           of the vertex is equal to the fixed primitive index for the
166           specified index type. The fixed index is equal to 2n−1 where n is
167           equal to 8 for GL_UNSIGNED_BYTE, 16 for GL_UNSIGNED_SHORT and 32
168           for GL_UNSIGNED_INT.
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170       GL_SAMPLE_ALPHA_TO_COVERAGE
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172           If enabled, compute a temporary coverage value where each bit is
173           determined by the alpha value at the corresponding sample location.
174           The temporary coverage value is then ANDed with the fragment
175           coverage value.
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177       GL_SAMPLE_ALPHA_TO_ONE
178
179           If enabled, each sample alpha value is replaced by the maximum
180           representable alpha value.
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182       GL_SAMPLE_COVERAGE
183
184           If enabled, the fragment's coverage is ANDed with the temporary
185           coverage value. If GL_SAMPLE_COVERAGE_INVERT is set to GL_TRUE,
186           invert the coverage value. See glSampleCoverage().
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188       GL_SAMPLE_SHADING
189
190           If enabled, the active fragment shader is run once for each covered
191           sample, or at fraction of this rate as determined by the current
192           value of GL_MIN_SAMPLE_SHADING_VALUE. See glMinSampleShading().
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194       GL_SAMPLE_MASK
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196           If enabled, the sample coverage mask generated for a fragment
197           during rasterization will be ANDed with the value of
198           GL_SAMPLE_MASK_VALUE before shading occurs. See glSampleMaski().
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200       GL_SCISSOR_TEST
201
202           If enabled, discard fragments that are outside the scissor
203           rectangle. See glScissor().
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205       GL_STENCIL_TEST
206
207           If enabled, do stencil testing and update the stencil buffer. See
208           glStencilFunc() and glStencilOp().
209
210       GL_TEXTURE_CUBE_MAP_SEAMLESS
211
212           If enabled, cubemap textures are sampled such that when linearly
213           sampling from the border between two adjacent faces, texels from
214           both faces are used to generate the final sample value. When
215           disabled, texels from only a single face are used to construct the
216           final sample value.
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218       GL_PROGRAM_POINT_SIZE
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220           If enabled and a vertex or geometry shader is active, then the
221           derived point size is taken from the (potentially clipped) shader
222           builtin gl_PointSize and clamped to the implementation-dependent
223           point size range.
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ERRORS

226       GL_INVALID_ENUM is generated if cap is not one of the values listed
227       previously.
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229       GL_INVALID_VALUE is generated by glEnablei and glDisablei if index is
230       greater than or equal to the number of indexed capabilities for cap.
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NOTES

233       GL_PRIMITIVE_RESTART is available only if the GL version is 3.1 or
234       greater.
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236       GL_TEXTURE_CUBE_MAP_SEAMLESS is available only if the GL version is 3.2
237       or greater.
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239       GL_PRIMITIVE_RESTART_FIXED_INDEX is available only if the GL version is
240       4.3 or greater.
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242       GL_DEBUG_OUTPUT and GL_DEBUG_OUTPUT_SYNCHRONOUS are available only if
243       the GL version is 4.3 or greater.
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245       Any token accepted by glEnable or glDisable is also accepted by
246       glEnablei and glDisablei, but if the capability is not indexed, the
247       maximum value that index may take is zero.
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249       In general, passing an indexed capability to glEnable or glDisable will
250       enable or disable that capability for all indices, resepectively.
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ASSOCIATED GETS

253       glIsEnabled()
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255       glGet()
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COPYRIGHT

265       Copyright © 1991-2006 Silicon Graphics, Inc. Copyright © 2010-2011
266       Khronos Group. This document is licensed under the SGI Free Software B
267       License. For details, see http://oss.sgi.com/projects/FreeB/.
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AUTHORS

270       opengl.org
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274opengl.org                        06/10/2014                      GLENABLE(3G)