GLAPI/glGetShaderPrecisionFormat

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glGetShaderPrecisionFormat
Core in version 4.4
Core since version 4.1
Core ARB extension ARB_ES2_compatibility

glGetShaderPrecisionFormat: retrieve the range and precision for numeric formats supported by the shader compiler

Function Definition

 void glGetShaderPrecisionFormat(GLenum shaderType​, GLenum precisionType​, GLint *range​, GLint *precision​);
shaderType
Specifies the type of shader whose precision to query. shaderType​ must be GL_VERTEX_SHADER​ or GL_FRAGMENT_SHADER​.
precisionType
Specifies the numeric format whose precision and range to query.
range
Specifies the address of array of two integers into which encodings of the implementation's numeric range are returned.
precision
Specifies the address of an integer into which the numeric precision of the implementation is written.

Description

glGetShaderPrecisionFormat retrieves the numeric range and precision for the implementation's representation of quantities in different numeric formats in specified shader type. shaderType​ specifies the type of shader for which the numeric precision and range is to be retrieved and must be one of GL_VERTEX_SHADER​ or GL_FRAGMENT_SHADER​. precisionType​ specifies the numeric format to query and must be one of GL_LOW_FLOAT​, GL_MEDIUM_FLOAT​GL_HIGH_FLOAT​, GL_LOW_INT​, GL_MEDIUM_INT​, or GL_HIGH_INT​.

range​ points to an array of two integers into which the format's numeric range will be returned. If min and max are the smallest values representable in the format, then the values returned are defined to be: range​[0] = floor(log2(|min|)) and range​[1] = floor(log2(|max|)).

precision​ specifies the address of an integer into which will be written the log2 value of the number of bits of precision of the format. If the smallest representable value greater than 1 is 1 + eps, then the integer addressed by precision​ will contain floor(-log2(eps)).

Errors

GL_INVALID_ENUM​ is generated if shaderType​ or precisionType​ is not an accepted value.

Copyright

Copyright © 2010 Khronos Group. This material may be distributed subject to the terms and conditions set forth in the Open Publication License, v 1.0, 8 June 1999. http://opencontent.org/openpub/.