glGetHistogramParameter.3gl

Langue: en

Version: 380415 (fedora - 01/12/10)

Section: 3 (Bibliothèques de fonctions)

NAME

glGetHistogramParameterfv, glGetHistogramParameteriv - 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
GL_HISTOGRAM_RED_SIZE Red component counter size, in bits
GL_HISTOGRAM_GREEN_SIZE Green component counter size, in bits

Parameter Description

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 GL_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(3G), glHistogram(3G)