GLGETCONVOLUTIONPARA(3G)

NAME
glGetConvolutionParameter - get convolution parameters

C SPECIFICATION

void glGetConvolutionParameterfv(GLenum target, GLenum pname, GLfloat * params);

void glGetConvolutionParameteriv(GLenum target, GLenum pname, GLint * params);

PARAMETERS

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()

COPYRIGHT

Copyright © 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.