glgethistogramparameter(3)
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.