glEnable

Name

glEnable , glDisable - enable or disable server-side GL capabilities

C Specification

void glEnable(GLenum cap)
void glDisable(GLenum cap)

Parameters

cap: Specifies a symbolic constant indicating a GL capability.

Description

glEnable and glDisable enable and disable various capabilities. The initial value for each capability with the exception of GL_DITHER and GL_MULTISAMPLE is GL_FALSE. The initial value for GL_DITHER and GL_MULTISAMPLE is GL_TRUE.

Both glEnable and glDisable take a single argument, cap, which can assume one of the following values:

GL_ALPHA_TEST: If enabled, do alpha testing. See glAlphaFunc.
GL_BLEND: If enabled, blend the incoming color values with the values in the color buffers. See glBlendFunc.
GL_CLIP_PLANEi: If enabled, clipping plane i is enabled. See glClipPlane.
GL_COLOR_LOGIC_OP: If enabled, apply the currently selected logical operation to the incoming color and color buffer values. See glLogicOp.
GL_COLOR_MATERIAL: If enabled, have ambient and diffuse material parameters track the current color.
GL_CULL_FACE: If enabled, cull polygons based on their winding in window coordinates. See glCullFace.
GL_DEPTH_TEST: If enabled, do depth comparisons and update the depth buffer. Note that even if the depth buffer exists and the depth mask is non-zero, the depth buffer is not updated if the depth test is disabled. See glDepthFunc, glDepthMask, and glDepthRange.
GL_DITHER: If enabled, dither color components or indices before they are written to the color buffer.
GL_FOG: If enabled, blend a fog color into the posttexturing color. See glFog.
GL_LIGHTi: If enabled, include light i in the evaluation of the lighting equation. See glLightModel and glLight.
GL_LIGHTING: If enabled, use the current lighting parameters to compute the vertex color. Otherwise, simply associate the current color with each vertex. See glMaterial, glLightModel, and glLight.
GL_LINE_SMOOTH: If enabled, draw lines with correct filtering. Otherwise, draw aliased lines. See glLineWidth.
GL_MATRIX_PALETTE_OES: If enabled, the matrix palette extension is enabled. See glMatrixMode.
GL_MULTISAMPLE: If enabled, perform multisampling of fragments for single-pass antialiasing and other effects. See glSampleCoverage.
GL_NORMALIZE: If enabled, normal vectors are scaled to unit length after transformation. See glNormal and glNormalPointer.
GL_POINT_SMOOTH: If enabled, draw points with proper filtering. Otherwise, draw aliased points. See glPointSize.
GL_POINT_SPRITE_OES: If enabled, point sprites are enabled. See glPointSize and glTexEnv
GL_POLYGON_OFFSET_FILL: If enabled, an offset is added to depth values of a polygon's fragments before the depth comparison is performed. See glPolygonOffset.
GL_RESCALE_NORMAL: If enabled, normal vectors are scaled by a factor derived from the modelview matrix. See glNormal and glNormalPointer.
GL_SAMPLE_ALPHA_TO_COVERAGE: If enabled, a temporary coverage value is generated where each bit is determined by the alpha value at the corresponding sample location. The temporary coverage value is then ANDed with the fragment coverage value. Otherwise the fragment coverage value is unchanged at this point. See glSampleCoverage.
GL_SAMPLE_ALPHA_TO_ONE: If enabled, each fragment alpha value is replaced by the maximum representable alpha value. Otherwise, the alpha values are not changed. See glSampleCoverage.
GL_SAMPLE_COVERAGE: If enabled, the fragment coverage is ANDed with another temporary coverage. This temporary coverage is generated in the same manner as for GL_SAMPLE_ALPHA_TO_COVERAGE described above, but as a function of the value of GL_SAMPLE_COVERAGE_VALUE. If GL_SAMPLE_COVERAGE_INVERT is GL_TRUE, the temporary coverage is inverted (all bit values are inverted) before it is ANDed with the fragment coverage. See glSampleCoverage.
GL_SCISSOR_TEST: If enabled, discard fragments that are outside the scissor rectangle. See glScissor.
GL_STENCIL_TEST: If enabled, do stencil testing and update the stencil buffer. See glStencilFunc, glStencilMask, and glStencilOp.
GL_TEXTURE_2D: If enabled, two-dimensional texturing is performed for the active texture unit. See glActiveTexture, glTexImage2D, glCompressedTexImage2D, and glCopyTexImage2D.

Errors

GL_INVALID_ENUM is generated if cap is not one of the values listed previously.

Copyright