1991-2006
Silicon Graphics, Inc.
2010-2014
Khronos Group
glGet
3G

# glGet

return the value or values of a selected parameter

## C Specification

                    void glGetBooleanv
                    GLenum pname
                    GLboolean * data

                    void glGetFloatv
                    GLenum pname
                    GLfloat * data

                    void glGetIntegerv
                    GLenum pname
                    GLint * data

                    void glGetInteger64v
                    GLenum pname
                    GLint64 * data

                    void glGetIntegeri_v
                    GLenum target
                    GLuint index
                    GLint * data

                    void glGetInteger64i_v
                    GLenum target
                    GLuint index
                    GLint64 * data

## Parameters

`pname`

  Specifies the parameter value to be returned. The symbolic constants in the list below are accepted.

`target`

  Specifies the parameter value to be returned for indexed versions of `glGet`. The symbolic constants in the list below are accepted.

`index`

  Specifies the index of the particular element being queried.

`data`

  Returns the value or values of the specified parameter.

## Description

These commands return values for simple state variables in GL. `pname` is a symbolic constant indicating the state variable to be returned, and `params` is a pointer to an array of the indicated type in which to place the returned data.

Type conversion is performed if `params` has a different type than the state variable value being requested. If `glGetBooleanv` is called, a floating-point (or integer) value is converted to `GL_FALSE` if and only if it is 0.0 (or 0). Otherwise, it is converted to `GL_TRUE`. If `glGetIntegerv` is called, boolean values are returned as `GL_TRUE` or `GL_FALSE`, and most floating-point values are rounded to the nearest integer value. Floating-point colors and normals, however, are returned with a linear mapping that maps 1.0 to the most positive representable integer value and -1.0 to the most negative representable integer value. If `glGetFloatv` is called, boolean values are returned as `GL_TRUE` or `GL_FALSE`, and integer values are converted to floating-point values.

The following symbolic constants are accepted by `pname`:

`GL_ACTIVE_TEXTURE`

  `params` returns a single value indicating the active multitexture unit. The initial value is `GL_TEXTURE0`. See glActiveTexture.

`GL_ALIASED_LINE_WIDTH_RANGE`

  `params` returns a pair of values indicating the range of widths supported for aliased lines. See glLineWidth.

`GL_ALIASED_POINT_SIZE_RANGE`

  `params` returns two values: the smallest and largest supported sizes for points. The smallest size must be at most 1, and the largest size must be at least 1.

`GL_ALPHA_BITS`

  `params` returns one value, the number of alpha bitplanes in the color buffer of the currently bound draw framebuffer. This is deﬁned only if all color attachments of the draw framebuffer have identical formats, in which case the number of alpha bits of color attachment zero are returned.

`GL_ARRAY_BUFFER_BINDING`

  `params` returns a single value, the name of the buffer object currently bound to the target `GL_ARRAY_BUFFER`. If no buffer object is bound to this target, 0 is returned. The initial value is 0. See glBindBuffer.

`GL_BLEND`

  `params` returns a single boolean value indicating whether blending is enabled. The initial value is `GL_FALSE`. See glBlendFunc.

`GL_BLEND_COLOR`

  `params` returns four values, the red, green, blue, and alpha values which are the components of the blend color. See glBlendColor.

`GL_BLEND_DST_ALPHA`

  `params` returns one value, the symbolic constant identifying the alpha destination blend function. The initial value is `GL_ZERO`. See glBlendFunc and glBlendFuncSeparate.

`GL_BLEND_DST_RGB`

  `params` returns one value, the symbolic constant identifying the RGB destination blend function. The initial value is `GL_ZERO`. See glBlendFunc and glBlendFuncSeparate.

`GL_BLEND_EQUATION_ALPHA`

  `params` returns one value, a symbolic constant indicating whether the Alpha blend equation is `GL_FUNC_ADD`, `GL_FUNC_SUBTRACT`, `GL_FUNC_REVERSE_SUBTRACT`, `GL_MIN` or `GL_MAX`. See glBlendEquationSeparate.

`GL_BLEND_EQUATION_RGB`

  `params` returns one value, a symbolic constant indicating whether the RGB blend equation is `GL_FUNC_ADD`, `GL_FUNC_SUBTRACT`, `GL_FUNC_REVERSE_SUBTRACT`, `GL_MIN` or `GL_MAX`. See glBlendEquationSeparate.

`GL_BLEND_SRC_ALPHA`

  `params` returns one value, the symbolic constant identifying the alpha source blend function. The initial value is `GL_ONE`. See glBlendFunc and glBlendFuncSeparate.

`GL_BLEND_SRC_RGB`

  `params` returns one value, the symbolic constant identifying the RGB source blend function. The initial value is `GL_ONE`. See glBlendFunc and glBlendFuncSeparate.

`GL_BLUE_BITS`

  `params` returns one value, the number of blue bitplanes in the color buffer of the currently bound draw framebuffer. This is deﬁned only if all color attachments of the draw framebuffer have identical formats, in which case the number of blue bits of color attachment zero are returned.

`GL_COLOR_CLEAR_VALUE`

  `params` returns four values: the red, green, blue, and alpha values used to clear the color buffers. Integer values, if requested, are linearly mapped from the internal floating-point representation such that 1.0 returns the most positive representable integer value, and -1.0 returns the most negative representable integer value. The initial value is (0, 0, 0, 0). See glClearColor.

`GL_COLOR_WRITEMASK`

  `params` returns four boolean values: the red, green, blue, and alpha write enables for the color buffers. The initial value is (`GL_TRUE`, `GL_TRUE`, `GL_TRUE`, `GL_TRUE`). See glColorMask.

`GL_COMPRESSED_TEXTURE_FORMATS`

  `params` returns a list of symbolic constants of length `GL_NUM_COMPRESSED_TEXTURE_FORMATS` indicating which compressed texture formats are available. See glCompressedTexImage2D.

`GL_COPY_READ_BUFFER_BINDING`

  `params` returns a single value, the name of the buffer object currently bound to the target `GL_COPY_READ_BUFFER`. If no buffer object is bound to this target, 0 is returned. The initial value is 0. See glBindBuffer.

`GL_COPY_WRITE_BUFFER_BINDING`

  `params` returns a single value, the name of the buffer object currently bound to the target `GL_COPY_WRITE_BUFFER`. If no buffer object is bound to this target, 0 is returned. The initial value is 0. See glBindBuffer.

`GL_CULL_FACE`

  `params` returns a single boolean value indicating whether polygon culling is enabled. The initial value is `GL_FALSE`. See glCullFace.

`GL_CULL_FACE_MODE`

  `params` returns a single value indicating the mode of polygon culling. The initial value is `GL_BACK`. See glCullFace.

`GL_CURRENT_PROGRAM`

  `params` returns one value, the name of the program object that is currently active, or 0 if no program object is active. See glUseProgram.

`GL_DEPTH_BITS`

  `params` returns one value, the number of bitplanes in the depth buffer of the currently bound framebuffer.

`GL_DEPTH_CLEAR_VALUE`

  `params` returns one value, the value that is used to clear the depth buffer. Integer values, if requested, are linearly mapped from the internal floating-point representation such that 1.0 returns the most positive representable integer value, and -1.0 returns the most negative representable integer value. The initial value is 1. See glClearDepthf.

`GL_DEPTH_FUNC`

  `params` returns one value, the symbolic constant that indicates the depth comparison function. The initial value is `GL_LESS`. See glDepthFunc.

`GL_DEPTH_RANGE`

  `params` returns two values: the near and far mapping limits for the depth buffer. Integer values, if requested, are linearly mapped from the internal floating-point representation such that 1.0 returns the most positive representable integer value, and -1.0 returns the most negative representable integer value. The initial value is (0, 1). See glDepthRangef.

`GL_DEPTH_TEST`

  `params` returns a single boolean value indicating whether depth testing of fragments is enabled. The initial value is `GL_FALSE`. See glDepthFunc and glDepthRangef.

`GL_DEPTH_WRITEMASK`

  `params` returns a single boolean value indicating if the depth buffer is enabled for writing. The initial value is `GL_TRUE`. See glDepthMask.

`GL_DITHER`

  `params` returns a single boolean value indicating whether dithering of fragment colors and indices is enabled. The initial value is `GL_TRUE`.

`GL_DRAW_BUFFER` i

  `params` returns one value, a symbolic constant indicating which buffers are being drawn to by the corresponding output color. See glDrawBuffers. The initial value of `GL_DRAW_BUFFER0` is `GL_BACK`. The initial values of draw buffers for all other output colors is `GL_NONE`.

`GL_DRAW_FRAMEBUFFER_BINDING`

  `params` returns one value, the name of the framebuffer object currently bound to the `GL_DRAW_FRAMEBUFFER` target. If the default framebuffer is bound, this value will be zero. The initial value is zero. See glBindFramebuffer.

`GL_ELEMENT_ARRAY_BUFFER_BINDING`

  `params` returns a single value, the name of the buffer object currently bound to the target `GL_ELEMENT_ARRAY_BUFFER`. If no buffer object is bound to this target, 0 is returned. The initial value is 0. See glBindBuffer.

`GL_FRAGMENT_SHADER_DERIVATIVE_HINT`

  `params` returns one value, a symbolic constant indicating the mode of the derivative accuracy hint for fragment shaders. The initial value is `GL_DONT_CARE`. See glHint.

`GL_FRONT_FACE`

  `params` returns a single value indicating the winding order of polygon front faces. The initial value is `GL_CCW`. See glFrontFace.

`GL_GENERATE_MIPMAP_HINT`

  `params` returns one value, a symbolic constant indicating the mode of the generate mipmap quality hint. The initial value is `GL_DONT_CARE`. See glHint.

`GL_GREEN_BITS`

  `params` returns one value, the number of green bitplanes in the color buffer of the currently bound draw framebuffer. This is deﬁned only if all color attachments of the draw framebuffer have identical formats, in which case the number of green bits of color attachment zero are returned.

`GL_IMPLEMENTATION_COLOR_READ_FORMAT`

  `params` returns one value, the format chosen by the implementation in which pixels may be read from the color buffer of the currently bound framebuffer in conjunction with `GL_IMPLEMENTATION_COLOR_READ_TYPE`. See glReadPixels.

`GL_IMPLEMENTATION_COLOR_READ_TYPE`

  `params` returns one value, the type chosen by the implementation with which pixels may be read from the color buffer of the currently bound framebuffer in conjunction with `GL_IMPLEMENTATION_COLOR_READ_FORMAT`. See glReadPixels.

`GL_LINE_WIDTH`

  `params` returns one value, the line width as specified with glLineWidth. The initial value is 1.

`GL_MAJOR_VERSION`

  `params` returns one value, the major version number of the OpenGL ES API supported by the current context. This must be 3.

`GL_MAX_3D_TEXTURE_SIZE`

  `params` returns one value, a rough estimate of the largest 3D texture that the GL can handle. The value must be at least 256. See glTexImage3D.

`GL_MAX_ARRAY_TEXTURE_LAYERS`

  `params` returns one value. The value indicates the maximum number of layers allowed in an array texture, and must be at least 256. See glTexImage2D.

`GL_MAX_COLOR_ATTACHMENTS`

  `params` returns one value, the maximum number of color attachment points in a framebuffer object. The value must be at least 4. See glFramebufferRenderbuffer and glFramebufferTexture2D.

`GL_MAX_COMBINED_FRAGMENT_UNIFORM_COMPONENTS`

  `params` returns one value, the number of words for fragment shader uniform variables in all uniform blocks (including default). The value must be at least `GL_MAX_FRAGMENT_UNIFORM_COMPONENTS` + `GL_MAX_UNIFORM_BLOCK_SIZE` * `GL_MAX_FRAGMENT_UNIFORM_BLOCKS` / 4. See glUniform.

`GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS`

  `params` returns one value, the maximum supported texture image units that can be used to access texture maps from the vertex shader and the fragment processor combined. If both the vertex shader and the fragment processing stage access the same texture image unit, then that counts as using two texture image units against this limit. The value must be at least 32. See glActiveTexture.

`GL_MAX_COMBINED_UNIFORM_BLOCKS`

  `params` returns one value, the maximum number of uniform blocks per program. The value must be at least 24. See glUniformBlockBinding.

`GL_MAX_COMBINED_VERTEX_UNIFORM_COMPONENTS`

  `params` returns one value, the number of words for vertex shader uniform variables in all uniform blocks (including default). The value must be at least . `GL_MAX_VERTEX_UNIFORM_COMPONENTS` + `GL_MAX_UNIFORM_BLOCK_SIZE` * `GL_MAX_VERTEX_UNIFORM_BLOCKS` / 4. See glUniform.

`GL_MAX_CUBE_MAP_TEXTURE_SIZE`

  `params` returns one value. The value gives a rough estimate of the largest cube-map texture that the GL can handle. The value must be at least 2048. See glTexImage2D.

`GL_MAX_DRAW_BUFFERS`

  `params` returns one value, the maximum number of simultaneous outputs that may be written in a fragment shader. The value must be at least 4. See glDrawBuffers.

`GL_MAX_ELEMENT_INDEX`

  `params` returns one value, the maximum index supported by the implementation. The value must be at least 2 24 - 1 .

`GL_MAX_ELEMENTS_INDICES`

  `params` returns one value, the recommended maximum number of vertex array indices. See glDrawRangeElements.

`GL_MAX_ELEMENTS_VERTICES`

  `params` returns one value, the recommended maximum number of vertex array vertices. See glDrawRangeElements.

`GL_MAX_FRAGMENT_INPUT_COMPONENTS`

  `params` returns one value, the maximum number of components of the inputs read by the fragment shader, which must be at least 60.

`GL_MAX_FRAGMENT_UNIFORM_BLOCKS`

  `params` returns one value, the maximum number of uniform blocks per fragment shader. The value must be at least 12. See glUniformBlockBinding.

`GL_MAX_FRAGMENT_UNIFORM_COMPONENTS`

  `params` returns one value, the maximum number of individual floating-point, integer, or boolean values that can be held in uniform variable storage for a fragment shader. The value must be at least 896. See glUniform.

`GL_MAX_FRAGMENT_UNIFORM_VECTORS`

  `params` returns one value, the maximum number of vector floating-point, integer, or boolean values that can be held in uniform variable storage for a fragment shader. The value must be at least 224. See glUniform.

`GL_MAX_PROGRAM_TEXEL_OFFSET`

  `params` returns one value, the maximum texel offset allowed in a texture lookup, which must be at least 7.

`GL_MAX_RENDERBUFFER_SIZE`

  `params` returns one value. The value indicates the maximum supported size for renderbuffers and must be at least 2048. See glFramebufferRenderbuffer.

`GL_MAX_SAMPLES`

  `params` returns one value. The value indicates the maximum supported number of samples for multisampling. The value must be at least 4. See glGetInternalformativ.

`GL_MAX_SERVER_WAIT_TIMEOUT`

  `params` returns one value, the maximum glWaitSync timeout interval.

`GL_MAX_TEXTURE_IMAGE_UNITS`

  `params` returns one value, the maximum supported texture image units that can be used to access texture maps from the fragment shader. The value must be at least 16. See glActiveTexture.

`GL_MAX_TEXTURE_LOD_BIAS`

  `params` returns one value, the maximum, absolute value of the texture level-of-detail bias. The value must be at least 2.0.

`GL_MAX_TEXTURE_SIZE`

  `params` returns one value. The value gives a rough estimate of the largest texture that the GL can handle. The value must be at least 2048. See glTexImage2D.

`GL_MAX_TRANSFORM_FEEDBACK_INTERLEAVED_COMPONENTS`

  `params` returns one value, the maximum number of components which can be written to a single transform feedback buffer in interleaved mode. The value must be at least 64. See glTransformFeedbackVaryings.

`GL_MAX_TRANSFORM_FEEDBACK_SEPARATE_ATTRIBS`

  `params` returns one value, the maximum separate attributes or outputs which can be captured in separate transform feedback mode. The value must be at least 4. See glTransformFeedbackVaryings.

`GL_MAX_TRANSFORM_FEEDBACK_SEPARATE_COMPONENTS`

  `params` returns one value, the maximum number of components which can be written per attribute or output in separate transform feedback mode. The value must be at least 4. See glTransformFeedbackVaryings.

`GL_MAX_UNIFORM_BLOCK_SIZE`

  `params` returns one value, the maximum size in basic machine units of a uniform block. The value must be at least 16384. See glUniformBlockBinding.

`GL_MAX_UNIFORM_BUFFER_BINDINGS`

  `params` returns one value, the maximum number of uniform buffer binding points on the context, which must be at least 24.

`GL_MAX_VARYING_COMPONENTS`

  `params` returns one value, the number components for varying variables, which must be at least 60.

`GL_MAX_VARYING_VECTORS`

  `params` returns one value, the maximum number of interpolators available for processing varying variables used by vertex and fragment shaders. This value represents the number of vector values that can be interpolated; varying variables declared as matrices and arrays will consume multiple interpolators. The value must be at least 15.

`GL_MAX_VERTEX_ATTRIBS`

  `params` returns one value, the maximum number of 4-component generic vertex attributes accessible to a vertex shader. The value must be at least 16. See glVertexAttrib.

`GL_MAX_VERTEX_TEXTURE_IMAGE_UNITS`

  `params` returns one value, the maximum supported texture image units that can be used to access texture maps from the vertex shader. The value may be at least 16. See glActiveTexture.

`GL_MAX_VERTEX_OUTPUT_COMPONENTS`

  `params` returns one value, the maximum number of components of output written by a vertex shader, which must be at least 64.

`GL_MAX_VERTEX_UNIFORM_BLOCKS`

  `params` returns one value, the maximum number of uniform blocks per vertex shader. The value must be at least 12. See glUniformBlockBinding.

`GL_MAX_VERTEX_UNIFORM_COMPONENTS`

  `params` returns one value, the maximum number of individual floating-point, integer, or boolean values that can be held in uniform variable storage for a vertex shader. The value must be at least 1024. See glUniform.

`GL_MAX_VERTEX_UNIFORM_VECTORS`

  `params` returns one value, the maximum number of vector floating-point, integer, or boolean values that can be held in uniform variable storage for a vertex shader. The value must be at least 256. See glUniform.

`GL_MAX_VIEWPORT_DIMS`

  `params` returns two values: the maximum supported width and height of the viewport. These must be at least as large as the visible dimensions of the display being rendered to. See glViewport.

`GL_MIN_PROGRAM_TEXEL_OFFSET`

  `params` returns one value, the minimum texel offset allowed in a texture lookup, which must be at most -8.

`GL_MINOR_VERSION`

  `params` returns one value, the minor version number of the OpenGL ES API supported by the current context.

`GL_NUM_COMPRESSED_TEXTURE_FORMATS`

  `params` returns a single integer value indicating the number of available compressed texture formats. The minimum value is 10. See glCompressedTexImage2D.

`GL_NUM_EXTENSIONS`

  `params` returns one value, the number of extensions supported by the GL implementation for the current context. See glGetString.

`GL_NUM_PROGRAM_BINARY_FORMATS`

  `params` returns a single integer value indicating the number of available program binary formats. The minimum value is 0. See glProgramBinary.

`GL_NUM_SHADER_BINARY_FORMATS`

  `params` returns a single integer value indicating the number of available shader binary formats. The minimum value is 0. See glShaderBinary.

`GL_PACK_ALIGNMENT`

  `params` returns one value, the byte alignment used for writing pixel data to memory. The initial value is 4. See glPixelStorei.

`GL_PACK_ROW_LENGTH`

  `params` returns one value, the row length used for writing pixel data to memory. The initial value is 0. See glPixelStorei.

`GL_PACK_SKIP_PIXELS`

  `params` returns one value, the number of pixel locations skipped before the first pixel is written into memory. The initial value is 0. See glPixelStorei.

`GL_PACK_SKIP_ROWS`

  `params` returns one value, the number of rows of pixel locations skipped before the first pixel is written into memory. The initial value is 0. See glPixelStorei.

`GL_PIXEL_PACK_BUFFER_BINDING`

  `params` returns a single value, the name of the buffer object currently bound to the target `GL_PIXEL_PACK_BUFFER`. If no buffer object is bound to this target, 0 is returned. The initial value is 0. See glBindBuffer.

`GL_PIXEL_UNPACK_BUFFER_BINDING`

  `params` returns a single value, the name of the buffer object currently bound to the target `GL_PIXEL_UNPACK_BUFFER`. If no buffer object is bound to this target, 0 is returned. The initial value is 0. See glBindBuffer.

`GL_POLYGON_OFFSET_FACTOR`

  `params` returns one value, the scaling factor used to determine the variable offset that is added to the depth value of each fragment generated when a polygon is rasterized. The initial value is 0. See glPolygonOffset.

`GL_POLYGON_OFFSET_FILL`

  `params` returns a single boolean value indicating whether polygon offset is enabled for polygons. The initial value is `GL_FALSE`. See glPolygonOffset.

`GL_POLYGON_OFFSET_UNITS`

  `params` returns one value. This value is multiplied by an implementation-specific value and then added to the depth value of each fragment generated when a polygon is rasterized. The initial value is 0. See glPolygonOffset.

`GL_PRIMITIVE_RESTART_FIXED_INDEX`

  `params` returns a single boolean value indicating whether primitive restart with a fixed index is enabled. The initial value is `GL_FALSE`.

`GL_PROGRAM_BINARY_FORMATS`

  `params` returns a list of symbolic constants of length `GL_NUM_PROGRAM_BINARY_FORMATS` indicating which program binary formats are available. See glProgramBinary.

`GL_READ_BUFFER`

  `params` returns one value, a symbolic constant indicating which color buffer is selected for reading. The initial value is `GL_BACK`. See glReadPixels.

`GL_READ_FRAMEBUFFER_BINDING`

  `params` returns one value, the name of the framebuffer object currently bound to the `GL_READ_FRAMEBUFFER` target. If the default framebuffer is bound, this value will be zero. The initial value is zero. See glBindFramebuffer.

`GL_RED_BITS`

  `params` returns one value, the number of red bitplanes in the color buffer of the currently bound draw framebuffer. This is deﬁned only if all color attachments of the draw framebuffer have identical formats, in which case the number of red bits of color attachment zero are returned.

`GL_RENDERBUFFER_BINDING`

  `params` returns a single value, the name of the renderbuffer object currently bound to the target `GL_RENDERBUFFER`. If no renderbuffer object is bound to this target, 0 is returned. The initial value is 0. See glBindRenderbuffer.

`GL_SAMPLE_ALPHA_TO_COVERAGE`

  `params` returns a single boolean value indicating whether modification of sample coverage based on alpha is enabled. The initial value is `GL_FALSE`. See glSampleCoverage.

`GL_SAMPLE_BUFFERS`

  `params` returns a single integer value indicating the number of sample buffers associated with the framebuffer. See glSampleCoverage.

`GL_SAMPLE_COVERAGE`

  `params` returns a single boolean value indicating whether modification of sample coverage based on the value specified by glSampleCoverage is enabled. The initial value is `GL_FALSE`.

`GL_SAMPLE_COVERAGE_INVERT`

  `params` returns a single boolean value indicating if the temporary coverage value should be inverted. See glSampleCoverage.

`GL_SAMPLE_COVERAGE_VALUE`

  `params` returns a single positive floating-point value indicating the current sample coverage value. See glSampleCoverage.

`GL_SAMPLER_BINDING`

  `params` returns a single value, the name of the sampler object currently bound to the active texture unit. The initial value is 0. See glBindSampler.

`GL_SAMPLES`

  `params` returns a single integer value indicating the coverage mask size. See glSampleCoverage.

`GL_SCISSOR_BOX`

  `params` returns four values: the x and y window coordinates of the scissor box, followed by its width and height. Initially the x and y window coordinates are both 0 and the width and height are set to the size of the window. See glScissor.

`GL_SCISSOR_TEST`

  `params` returns a single boolean value indicating whether scissoring is enabled. The initial value is `GL_FALSE`. See glScissor.

`GL_SHADER_BINARY_FORMATS`

  `params` returns a list of symbolic constants of length `GL_NUM_SHADER_BINARY_FORMATS` indicating which shader binary formats are available. See glShaderBinary.

`GL_SHADER_COMPILER`

  `params` returns a single boolean value indicating whether a shader compiler is supported. This value is always `GL_TRUE`. See glCompileShader.

`GL_STENCIL_BACK_FAIL`

  `params` returns one value, a symbolic constant indicating what action is taken for back-facing polygons when the stencil test fails. The initial value is `GL_KEEP`. See glStencilOpSeparate.

`GL_STENCIL_BACK_FUNC`

  `params` returns one value, a symbolic constant indicating what function is used for back-facing polygons to compare the stencil reference value with the stencil buffer value. The initial value is `GL_ALWAYS`. See glStencilFuncSeparate.

`GL_STENCIL_BACK_PASS_DEPTH_FAIL`

  `params` returns one value, a symbolic constant indicating what action is taken for back-facing polygons when the stencil test passes, but the depth test fails. The initial value is `GL_KEEP`. See glStencilOpSeparate.

`GL_STENCIL_BACK_PASS_DEPTH_PASS`

  `params` returns one value, a symbolic constant indicating what action is taken for back-facing polygons when the stencil test passes and the depth test passes. The initial value is `GL_KEEP`. See glStencilOpSeparate.

`GL_STENCIL_BACK_REF`

  `params` returns one value, the reference value that is compared with the contents of the stencil buffer for back-facing polygons. The initial value is 0. See glStencilFuncSeparate.

`GL_STENCIL_BACK_VALUE_MASK`

  `params` returns one value, the mask that is used for back-facing polygons to mask both the stencil reference value and the stencil buffer value before they are compared. The initial value is all 1's. See glStencilFuncSeparate.

`GL_STENCIL_BACK_WRITEMASK`

  `params` returns one value, the mask that controls writing of the stencil bitplanes for back-facing polygons. The initial value is all 1's. See glStencilMaskSeparate.

`GL_STENCIL_BITS`

  `params` returns one value, the number of bitplanes in the stencil buffer of the currently bound framebuffer.

`GL_STENCIL_CLEAR_VALUE`

  `params` returns one value, the index to which the stencil bitplanes are cleared. The initial value is 0. See glClearStencil.

`GL_STENCIL_FAIL`

  `params` returns one value, a symbolic constant indicating what action is taken when the stencil test fails. The initial value is `GL_KEEP`. See glStencilOp. This stencil state only affects non-polygons and front-facing polygons. Back-facing polygons use separate stencil state. See glStencilOpSeparate.

`GL_STENCIL_FUNC`

  `params` returns one value, a symbolic constant indicating what function is used to compare the stencil reference value with the stencil buffer value. The initial value is `GL_ALWAYS`. See glStencilFunc. This stencil state only affects non-polygons and front-facing polygons. Back-facing polygons use separate stencil state. See glStencilFuncSeparate.

`GL_STENCIL_PASS_DEPTH_FAIL`

  `params` returns one value, a symbolic constant indicating what action is taken when the stencil test passes, but the depth test fails. The initial value is `GL_KEEP`. See glStencilOp. This stencil state only affects non-polygons and front-facing polygons. Back-facing polygons use separate stencil state. See glStencilOpSeparate.

`GL_STENCIL_PASS_DEPTH_PASS`

  `params` returns one value, a symbolic constant indicating what action is taken when the stencil test passes and the depth test passes. The initial value is `GL_KEEP`. See glStencilOp. This stencil state only affects non-polygons and front-facing polygons. Back-facing polygons use separate stencil state. See glStencilOpSeparate.

`GL_STENCIL_REF`

  `params` returns one value, the reference value that is compared with the contents of the stencil buffer. The initial value is 0. See glStencilFunc. This stencil state only affects non-polygons and front-facing polygons. Back-facing polygons use separate stencil state. See glStencilFuncSeparate.

`GL_STENCIL_TEST`

  `params` returns a single boolean value indicating whether stencil testing of fragments is enabled. The initial value is `GL_FALSE`. See glStencilFunc and glStencilOp.

`GL_STENCIL_VALUE_MASK`

  `params` returns one value, the mask that is used to mask both the stencil reference value and the stencil buffer value before they are compared. The initial value is all 1's. See glStencilFunc. This stencil state only affects non-polygons and front-facing polygons. Back-facing polygons use separate stencil state. See glStencilFuncSeparate.

`GL_STENCIL_WRITEMASK`

  `params` returns one value, the mask that controls writing of the stencil bitplanes. The initial value is all 1's. See glStencilMask. This stencil state only affects non-polygons and front-facing polygons. Back-facing polygons use separate stencil state. See glStencilMaskSeparate.

`GL_SUBPIXEL_BITS`

  `params` returns one value, an estimate of the number of bits of subpixel resolution that are used to position rasterized geometry in window coordinates. The value must be at least 4.

`GL_TEXTURE_BINDING_2D`

  `params` returns a single value, the name of the texture currently bound to the target `GL_TEXTURE_2D`. The initial value is 0. See glBindTexture.

`GL_TEXTURE_BINDING_2D_ARRAY`

  `params` returns a single value, the name of the texture currently bound to the target `GL_TEXTURE_2D_ARRAY`. The initial value is 0. See glBindTexture.

`GL_TEXTURE_BINDING_3D`

  `params` returns a single value, the name of the texture currently bound to the target `GL_TEXTURE_3D`. The initial value is 0. See glBindTexture.

`GL_TEXTURE_BINDING_CUBE_MAP`

  `params` returns a single value, the name of the texture currently bound to the target `GL_TEXTURE_CUBE_MAP`. The initial value is 0. See glBindTexture.

`GL_TRANSFORM_FEEDBACK_BINDING`

  `params` returns a single value, the name of the transform feedback object currently bound to the `GL_TRANSFORM_FEEDBACK` target. If no transform feedback object is bound to this target, 0 is returned. The initial value is 0. See glBindTransformFeedback.

`GL_TRANSFORM_FEEDBACK_ACTIVE`

  `params` returns a single boolean value indicating if the currently bound transform feedback object is active. See glBeginTransformFeedback and glResumeTransformFeedback.

`GL_TRANSFORM_FEEDBACK_BUFFER_BINDING`

  When used with non-indexed variants of `glGet` (such as `glGetIntegerv`), `params` returns a single value, the name of the buffer object currently bound to the target `GL_TRANSFORM_FEEDBACK_BUFFER`. If no buffer object is bound to this target, 0 is returned. When used with indexed variants of `glGet` (such as `glGetIntegeri_v`), `params` returns a single value, the name of the buffer object bound to the indexed transform feedback attribute stream. The initial value is 0 for all targets. See glBindBuffer, glBindBufferBase, and glBindBufferRange.

`GL_TRANSFORM_FEEDBACK_PAUSED`

  `params` returns a single boolean value indicating if the currently bound transform feedback object is paused. See glPauseTransformFeedback.

`GL_TRANSFORM_FEEDBACK_BUFFER_SIZE`

  When used with indexed variants of `glGet` (such as `glGetInteger64i_v`), `params` returns a single value, the size of the binding range for each transform feedback attribute stream. The initial value is 0 for all streams. See glBindBufferRange.

`GL_TRANSFORM_FEEDBACK_BUFFER_START`

  When used with indexed variants of `glGet` (such as `glGetInteger64i_v`), `params` returns a single value, the start offset of the binding range for each transform feedback attribute stream. The initial value is 0 for all streams. See glBindBufferRange.

`GL_UNIFORM_BUFFER_BINDING`

  When used with non-indexed variants of `glGet` (such as `glGetIntegerv`), `params` returns a single value, the name of the buffer object currently bound to the target `GL_UNIFORM_BUFFER`. If no buffer object is bound to this target, 0 is returned. When used with indexed variants of `glGet` (such as `glGetIntegeri_v`), `params` returns a single value, the name of the buffer object bound to the indexed uniform buffer binding point. The initial value is 0 for all targets. See glBindBuffer, glBindBufferBase, and glBindBufferRange.

`GL_UNIFORM_BUFFER_OFFSET_ALIGNMENT`

  `params` returns a single value, the minimum required alignment for uniform buffer sizes and offset. The initial value is 1. See glUniformBlockBinding.

`GL_UNIFORM_BUFFER_SIZE`

  When used with indexed variants of `glGet` (such as `glGetInteger64i_v`), `params` returns a single value, the size of the binding range for each indexed uniform buffer binding. The initial value is 0 for all bindings. See glBindBufferRange.

`GL_UNIFORM_BUFFER_START`

  When used with indexed variants of `glGet` (such as `glGetInteger64i_v`), `params` returns a single value, the start offset of the binding range for each indexed uniform buffer binding. The initial value is 0 for all bindings. See glBindBufferRange.

`GL_UNPACK_ALIGNMENT`

  `params` returns one value, the byte alignment used for reading pixel data from memory. The initial value is 4. See glPixelStorei.

`GL_UNPACK_IMAGE_HEIGHT`

  `params` returns one value, the image height used for reading pixel data from memory. The initial is 0. See glPixelStorei.

`GL_UNPACK_ROW_LENGTH`

  `params` returns one value, the row length used for reading pixel data from memory. The initial value is 0. See glPixelStorei.

`GL_UNPACK_SKIP_IMAGES`

  `params` returns one value, the number of pixel images skipped before the first pixel is read from memory. The initial value is 0. See glPixelStorei.

`GL_UNPACK_SKIP_PIXELS`

  `params` returns one value, the number of pixel locations skipped before the first pixel is read from memory. The initial value is 0. See glPixelStorei.

`GL_UNPACK_SKIP_ROWS`

  `params` returns one value, the number of rows of pixel locations skipped before the first pixel is read from memory. The initial value is 0. See glPixelStorei.

`GL_VERTEX_ARRAY_BINDING`

  `params` returns a single value, the name of the vertex array object currently bound. If no vertex array object is bound, 0 is returned. The initial value is 0. See glBindVertexArray.

`GL_VIEWPORT`

  `params` returns four values: the x and y window coordinates of the viewport, followed by its width and height. Initially the x and y window coordinates are both set to 0, and the width and height are set to the width and height of the window into which the GL will do its rendering. See glViewport.

Many of the boolean parameters can also be queried more easily using glIsEnabled.

## Notes

The following parameters return the associated value for the active texture unit: `GL_TEXTURE_2D`, `GL_TEXTURE_BINDING_2D`, `GL_TEXTURE_3D` and `GL_TEXTURE_BINDING_3D`.

## Errors

`GL_INVALID_ENUM` is generated if `pname` is not an accepted value.

`GL_INVALID_VALUE` is generated on either `glGetIntegeri_v`, or `glGetInteger64i_v` if `index` is outside of the valid range for the indexed state `target`.

## API Version Support

`glGetBooleanv`
`glGetFloatv`
`glGetIntegerv`
`glGetInteger64v`
`glGetIntegeri_v`
`glGetInteger64i_v`

## See Also

glGetActiveUniform, glGetAttachedShaders, glGetAttribLocation, glGetBufferParameter, glGetBufferPointerv, glGetError, glGetProgramiv, glGetProgramInfoLog, glGetQueryiv, glGetQueryObjectuiv, glGetShaderiv, glGetShaderInfoLog, glGetShaderSource, glGetString, glGetTexParameter, glGetUniform, glGetUniformLocation, glGetVertexAttrib, glGetVertexAttribPointerv, glIsEnabled

## Copyright

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/.