gethistogramparameter.3gl   [plain text]


'\" t
'\"! tbl | mmdoc
'\"macro stdmacro
.ds Vn Version 1.2
.ds Dt 24 September 1999
.ds Re Release 1.2.1
.ds Dp Jan 14 18:30
.ds Dm 001 gethisto
.ds Xs 33049 5 gethistogramparameter.gl
.TH GLGETHISTOGRAMPARAMETER 3G
.SH NAME
.B "glGetHistogramParameterfv, glGetHistogramParameteriv
\- get histogram parameters

.SH C SPECIFICATION
void \f3glGetHistogramParameterfv\fP(
GLenum \fItarget\fP,
.nf
.ta \w'\f3void \fPglGetHistogramParameterfv( 'u
	GLenum \fIpname\fP,
	GLfloat \fI*params\fP )
.fi
void \f3glGetHistogramParameteriv\fP(
GLenum \fItarget\fP,
.nf
.ta \w'\f3void \fPglGetHistogramParameteriv( 'u
	GLenum \fIpname\fP,
	GLint \fI*params\fP )
.fi

.SH PARAMETERS
.TP \w'\f2target\fP\ \ 'u 
\f2target\fP
Must be one of
\%\f3GL_HISTOGRAM\fP or
\%\f3GL_PROXY_HISTOGRAM\fP.
.TP
\f2pname\fP
The name of the parameter to be retrieved.
Must be one of
\%\f3GL_HISTOGRAM_WIDTH\fP,
\%\f3GL_HISTOGRAM_FORMAT\fP,
\%\f3GL_HISTOGRAM_RED_SIZE\fP,
\%\f3GL_HISTOGRAM_GREEN_SIZE\fP,
\%\f3GL_HISTOGRAM_BLUE_SIZE\fP,
\%\f3GL_HISTOGRAM_ALPHA_SIZE\fP,
\%\f3GL_HISTOGRAM_LUMINANCE_SIZE\fP, or
\%\f3GL_HISTOGRAM_SINK\fP.
.TP
\f2params\fP
Pointer to storage for the returned values.
.SH DESCRIPTION
\%\f3glGetHistogramParameter\fP is used to query parameter values for the current histogram or for
a proxy.  The histogram state information may be queried by calling
\%\f3glGetHistogramParameter\fP with a \f2target\fP of \%\f3GL_HISTOGRAM\fP (to
obtain information for the current histogram table) or
\%\f3GL_PROXY_HISTOGRAM\fP (to obtain information from the most recent
proxy request) and one of the following values for the \f2pname\fP argument:
.P
.ne
.TS
center;
lb lb
l l.
_
Parameter	Description
_
\%\f3GL_HISTOGRAM_WIDTH\fP	Histogram table width
\%\f3GL_HISTOGRAM_FORMAT\fP	Internal 
\%\f3GL_HISTOGRAM_RED_SIZE\fP	Red component counter size, in bits
\%\f3GL_HISTOGRAM_GREEN_SIZE\fP	Green component counter size, in bits
.TE
.bp
.TS
center;
lb lb
l l.
_
Parameter	Description
_
\%\f3GL_HISTOGRAM_BLUE_SIZE\fP	Blue component counter size, in bits
\%\f3GL_HISTOGRAM_ALPHA_SIZE\fP	Alpha component counter size, in bits
\%\f3GL_HISTOGRAM_LUMINANCE_SIZE\fP	Luminance component counter size, in bits
\%\f3GL_HISTOGRAM_SINK\fP	Value of the \f2sink\fP parameter
_
.TE

.SH NOTES
\%\f3glGetHistogramParameter\fP is present only if \%\f3GL_ARB_imaging\fP is returned when \%\f3glGetString\fP
is called with an argument of \%\f3GL_EXTENSIONS\fP.
.SH ERRORS
\%\f3GL_INVALID_ENUM\fP is generated if \f2target\fP is not one of the allowable
values.
.P
\%\f3GL_INVALID_ENUM\fP is generated if \f2pname\fP is not one of the allowable
values.
.P
\%\f3GL_INVALID_OPERATION\fP is generated if \%\f3glGetHistogramParameter\fP is executed
between the execution of \%\f3glBegin\fP and the corresponding
execution of \%\f3glEnd\fP.
.SH SEE ALSO
\%\f3glGetHistogram(3G)\fP,
\%\f3glHistogram(3G)\fP