glGetHistogramParameter : PyOpenGL 3.1.4 GL Man Pages

get histogram parameters

Signature

glGetHistogramParameter( )->

glGetHistogramParameterfv( GLenum ( target ) , GLenum ( pname ) , GLfloat * ( params ) )-> void

glGetHistogramParameterfv( target , pname , params )

glGetHistogramParameteriv( GLenum ( target ) , GLenum ( pname ) , GLint * ( params ) )-> void

glGetHistogramParameteriv( target , pname , params )

Parameters

Variables	Description
target	Must be one of GL_HISTOGRAM or GL_PROXY_HISTOGRAM .
pname	The name of the parameter to be retrieved. Must be one of GL_HISTOGRAM_WIDTH , GL_HISTOGRAM_FORMAT , GL_HISTOGRAM_RED_SIZE , GL_HISTOGRAM_GREEN_SIZE , GL_HISTOGRAM_BLUE_SIZE , GL_HISTOGRAM_ALPHA_SIZE , GL_HISTOGRAM_LUMINANCE_SIZE , or GL_HISTOGRAM_SINK .
params	Pointer to storage for the returned values.

Description

glGetHistogramParameter is used to query parameter values for the current histogram or for a proxy. The histogram state information may be queried by calling glGetHistogramParameter with a target of GL_HISTOGRAM (to obtain information for the current histogram table) or GL_PROXY_HISTOGRAM (to obtain information from the most recent proxy request) and one of the following values for the pname argument:

Parameter	Description
GL_HISTOGRAM_WIDTH	Histogram table width
GL_HISTOGRAM_FORMAT	Internal format
GL_HISTOGRAM_RED_SIZE	Red component counter size, in bits
GL_HISTOGRAM_GREEN_SIZE	Green component counter size, in bits
GL_HISTOGRAM_BLUE_SIZE	Blue component counter size, in bits
GL_HISTOGRAM_ALPHA_SIZE	Alpha component counter size, in bits
GL_HISTOGRAM_LUMINANCE_SIZE	Luminance component counter size, in bits
GL_HISTOGRAM_SINK	Value of the sink parameter

Notes

glGetHistogramParameter is present only if

ARB_imaging

is returned when glGetString is called with an argument of GL_EXTENSIONS .

Errors

GL_INVALID_ENUM is generated if target is not one of the allowable values.

GL_INVALID_ENUM is generated if pname is not one of the allowable values.

GL_INVALID_OPERATION is generated if glGetHistogramParameter is executed between the execution of glBegin and the corresponding execution of glEnd .

Copyright

1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/ .

glGetHistogramParameter