glGetConvolutionParameter

get convolution parameters

Signature

glGetConvolutionParameter( )->
glGetConvolutionParameterfv( GLenum ( target ) , GLenum ( pname ) , GLfloat * ( params ) )-> void
glGetConvolutionParameterfv( target , pname , params )
glGetConvolutionParameteriv( GLenum ( target ) , GLenum ( pname ) , GLint * ( params ) )-> void
glGetConvolutionParameteriv( target , pname , params )

Parameters

VariablesDescription
target
The filter whose parameters are to be retrieved. Must be one of GL_CONVOLUTION_1D , GL_CONVOLUTION_2D , or GL_SEPARABLE_2D .
pname
The parameter to be retrieved. Must be one of GL_CONVOLUTION_BORDER_MODE , GL_CONVOLUTION_BORDER_COLOR , GL_CONVOLUTION_FILTER_SCALE , GL_CONVOLUTION_FILTER_BIAS , GL_CONVOLUTION_FORMAT , GL_CONVOLUTION_WIDTH , GL_CONVOLUTION_HEIGHT , GL_MAX_CONVOLUTION_WIDTH , or GL_MAX_CONVOLUTION_HEIGHT .
params
Pointer to storage for the parameters to be retrieved.

Description

glGetConvolutionParameter retrieves convolution parameters. target determines which convolution filter is queried. pname determines which parameter is returned:
GL_CONVOLUTION_BORDER_MODE
The convolution border mode. See glConvolutionParameter for a list of border modes.
GL_CONVOLUTION_BORDER_COLOR
The current convolution border color. params must be a pointer to an array of four elements, which will receive the red, green, blue, and alpha border colors.
GL_CONVOLUTION_FILTER_SCALE
The current filter scale factors. params must be a pointer to an array of four elements, which will receive the red, green, blue, and alpha filter scale factors in that order.
GL_CONVOLUTION_FILTER_BIAS
The current filter bias factors. params must be a pointer to an array of four elements, which will receive the red, green, blue, and alpha filter bias terms in that order.
GL_CONVOLUTION_FORMAT
The current internal format. See glConvolutionFilter1D , glConvolutionFilter2D , and glSeparableFilter2D for lists of allowable formats.
GL_CONVOLUTION_WIDTH
The current filter image width.
GL_CONVOLUTION_HEIGHT
The current filter image height.
GL_MAX_CONVOLUTION_WIDTH
The maximum acceptable filter image width.
GL_MAX_CONVOLUTION_HEIGHT
The maximum acceptable filter image height.

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_ENUM is generated if target is GL_CONVOLUTION_1D and pname is GL_CONVOLUTION_HEIGHT or GL_MAX_CONVOLUTION_HEIGHT .
GL_INVALID_OPERATION is generated if glGetConvolutionParameter is executed between the execution of glBegin and the corresponding execution of glEnd .

See Also

glGetConvolutionFilter , glGetSeparableFilter , glConvolutionParameter

Sample Code References

The following code samples have been found which appear to reference the functions described here. Take care that the code may be old, broken or not even use PyOpenGL.

glGetConvolutionParameteriv
OpenGLContext tests/nehe6_convolve.py Lines: 112, 115

Copyright Notices

This documentation is based on documentation licensed under the SGI Free Software License B.