table of contents
GLGETHISTOGRAMPARAMETER(3G) | 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:
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)