%mathent; ]> 1991-2006 Silicon Graphics, Inc. 2010-2014 Khronos Group glGet 3G glGet return the value or values of a selected parameter 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 glGetBooleani_v GLenum target GLuint index GLboolean * data void glGetIntegeri_v GLenum target GLuint index GLint * data void glGetInteger64i_v GLenum target GLuint index GLint64 * data 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. 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_DISPATCH_INDIRECT_BUFFER_BINDING params returns a single value, the name of the buffer object currently bound to the target GL_DISPATCH_INDIRECT_BUFFER. If no buffer object is bound to this target, 0 is returned. The initial value is 0. See glBindBuffer. 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_BUFFERi 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_IMAGE_BINDING_LAYERED params returns one value, corresponding to whether the image bound to the indexed image unit is layered or not. 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_COLOR_TEXTURE_SAMPLES params returns one value, the maximum number of samples in a color multisample texture. GL_MAX_COMBINED_ATOMIC_COUNTERS params returns a single value, the maximum number of atomic counters available to all active shaders. GL_MAX_COMBINED_COMPUTE_UNIFORM_COMPONENTS params returns one value, the number of words for compute shader uniform variables in all uniform blocks (including default). The value must be at least 1. See glUniform. 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_SHADER_STORAGE_BLOCKS params returns one value, the maximum total number of active shader storage blocks that may be accessed by all active shaders. 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_COMPUTE_ATOMIC_COUNTERS params returns a single value, the maximum number of atomic counters available to compute shaders. GL_MAX_COMPUTE_ATOMIC_COUNTER_BUFFERS params returns a single value, the maximum number of atomic counter buffers that may be accessed by a compute shader. GL_MAX_COMPUTE_SHADER_STORAGE_BLOCKS params returns one value, the maximum number of active shader storage blocks that may be accessed by a compute shader. GL_MAX_COMPUTE_TEXTURE_IMAGE_UNITS params returns one value, the maximum supported texture image units that can be used to access texture maps from the compute shader. The value may be at least 16. See glActiveTexture. GL_MAX_COMPUTE_UNIFORM_BLOCKS params returns one value, the maximum number of uniform blocks per compute shader. The value must be at least 14. See glUniformBlockBinding. GL_MAX_COMPUTE_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 compute shader. The value must be at least 1024. See glUniform. GL_MAX_COMPUTE_WORK_GROUP_INVOCATIONS params returns one value, the number of invocations in a single local work group (i.e., the product of the three dimensions) that may be dispatched to a compute shader. GL_MAX_COMPUTE_WORK_GROUP_COUNT Accepted by the indexed versions of glGet. params the maximum number of work groups that may be dispatched to a compute shader. Indices 0, 1, and 2 correspond to the X, Y and Z dimensions, respectively. GL_MAX_COMPUTE_WORK_GROUP_SIZE Accepted by the indexed versions of glGet. params the maximum size of a work groups that may be used during compilation of a compute shader. Indices 0, 1, and 2 correspond to the X, Y and Z dimensions, respectively. 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_ATOMIC_COUNTERS params returns a single value, the maximum number of atomic counters available to fragment shaders. 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_SHADER_STORAGE_BLOCKS params returns one value, the maximum number of active shader storage blocks that may be accessed by a fragment shader. 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_FRAMEBUFFER_HEIGHT params returns one value, the maximum height for a framebuffer that has no attachments, which must be at least 16384. See glFramebufferParameteri. GL_MAX_FRAMEBUFFER_SAMPLES params returns one value, the maximum samples in a framebuffer that has no attachments, which must be at least 4. See glFramebufferParameteri. GL_MAX_FRAMEBUFFER_WIDTH params returns one value, the maximum width for a framebuffer that has no attachments, which must be at least 16384. See glFramebufferParameteri. GL_MAX_INTEGER_SAMPLES params returns one value, the maximum number of samples supported in integer format multisample buffers. 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_SAMPLE_MASK_WORDS params returns one value, the maximum number of sample mask words. 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_SHADER_STORAGE_BUFFER_BINDINGS params returns one value, the maximum number of shader storage buffer binding points on the context, which must be at least 8. 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_UNIFORM_LOCATIONS params returns one value, the maximum number of explicitly assignable uniform locations, which must be at least 1024. 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_ATOMIC_COUNTERS params returns a single value, the maximum number of atomic counters available to vertex shaders. GL_MAX_VERTEX_ATTRIB_BINDINGS params returns a single integer value containing the maximum number of vertex buffers that may be bound. GL_MAX_VERTEX_ATTRIB_RELATIVE_OFFSET params returns a single integer value containing the maximum offset that may be added to a vertex binding offset. 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_SHADER_STORAGE_BLOCKS params returns one value, the maximum number of active shader storage blocks that may be accessed by a vertex shader. 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_PROGRAM_PIPELINE_BINDING params a single value, the name of the currently bound program pipeline object, or zero if no program pipeline object is bound. See glBindProgramPipeline. 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_SHADER_STORAGE_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_SHADER_STORAGE_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 shader storage buffer binding points. The initial value is 0 for all targets. See glBindBuffer, glBindBufferBase, and glBindBufferRange. GL_SHADER_STORAGE_BUFFER_OFFSET_ALIGNMENT params returns a single value, the minimum required alignment for shader storage buffer sizes and offset. The initial value is 1. See glShaderStorateBlockBinding. GL_SHADER_STORAGE_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 shader storage buffer binding. The initial value is 0 for all bindings. See glBindBufferRange. GL_SHADER_STORAGE_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 shader storage buffer binding. The initial value is 0 for all bindings. See glBindBufferRange. 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_TEXTURE_BINDING_2D_MULTISAMPLE params returns a single value, the name of the texture currently bound to the target GL_TEXTURE_2D_MULTISAMPLE. The initial value is 0. See glBindTexture. GL_TEXTURE_BINDING_2D_MULTISAMPLE_ARRAY params returns a single value, the name of the texture currently bound to the target GL_TEXTURE_2D_MULTISAMPLE_ARRAY. 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_VERTEX_BINDING_DIVISOR Accepted by the indexed forms. params returns a single integer value representing the instance step divisor of the first element in the bound buffer's data store for vertex attribute bound to index. GL_VERTEX_BINDING_OFFSET Accepted by the indexed forms. params returns a single integer value representing the byte offset of the first element in the bound buffer's data store for vertex attribute bound to index. GL_VERTEX_BINDING_STRIDE Accepted by the indexed forms. params returns a single integer value representing the byte offset between the start of each element in the bound buffer's data store for vertex attribute bound to index. 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. 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. GL_MAX_VERTEX_ATOMIC_COUNTERS, GL_MAX_FRAMGENT_ATOMIC_COUNTERS, GL_MAX_COMPUTE_ATOMIC_COUNTERS, GL_MAX_COMBINED_ATOMIC_COUNTERS, GL_MAX_COMPUTE_UNIFORM_BLOCKS, GL_MAX_COMPUTE_TEXTURE_IMAGE_UNITS, GL_MAX_COMPUTE_UNIFORM_COMPONENTS, GL_MAX_COMPUTE_ATOMIC_COUNTER_BUFFERS, GL_MAX_COMBINED_COMPUTE_UNIFORM_COMPONENTS, GL_MAX_COMPUTE_WORK_GROUP_INVOCATIONS, GL_MAX_COMPUTE_WORK_GROUP_COUNT, GL_MAX_COMPUTE_WORK_GROUP_SIZE, GL_DISPATCH_INDIRECT_BUFFER_BINDING, GL_MAX_UNIFORM_LOCATIONS, GL_MAX_FRAMEBUFFER_WIDTH, GL_MAX_FRAMEBUFFER_HEIGHT, GL_MAX_FRAMEBUFFER_SAMPLES, GL_MAX_VERTEX_SHADER_STORAGE_BLOCKS, GL_MAX_FRAGMENT_SHADER_STORAGE_BLOCKS, GL_MAX_COMPUTE_SHADER_STORAGE_BLOCKS, GL_MAX_COMBINED_SHADER_STORAGE_BLOCKS, GL_VERTEX_BINDING_DIVISOR, GL_VERTEX_BINDING_OFFSET, GL_VERTEX_BINDING_STRIDE, GL_MAX_VERTEX_ATTRIB_RELATIVE_OFFSET and GL_MAX_VERTEX_ATTRIB_BINDINGS are available only if the GL ES version is 3.1 or greater. 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. glGetBooleanv glGetBooleani_v glGetFloatv glGetIntegerv glGetInteger64v glGetIntegeri_v glGetInteger64i_v glGetActiveUniform, glGetAttachedShaders, glGetAttribLocation, glGetBufferParameter, glGetBufferPointerv, glGetError, glGetProgramiv, glGetProgramInfoLog, glGetQueryiv, glGetQueryObjectuiv, glGetShaderiv, glGetShaderInfoLog, glGetShaderSource, glGetString, glGetTexParameter, glGetUniform, glGetUniformLocation, glGetVertexAttrib, glGetVertexAttribPointerv, glIsEnabled 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/.