GLGETHISTOGRAMPARAME(3G)

NAME
glGetHistogramParameter - get histogram parameters

C SPECIFICATION

void glGetHistogramParameterfv(GLenum target, GLenum pname, GLfloat * params);

void glGetHistogramParameteriv(GLenum target, GLenum pname, GLint * params);

PARAMETERS

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().

SEE ALSO

glGetHistogram(), glHistogram()

COPYRIGHT

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/.

AUTHORS

opengl.org