glGetHistogramParameter(3G) OpenGL Reference glGetHistogramParameter(3G)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:
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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
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glGetHistogramParameter(3G) OpenGL Reference glGetHistogramParameter(3G)
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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
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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, glHistogram
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