fglGetSeparableFilter(3G) OpenGL Reference fglGetSeparableFilter(3G)NAMEfglGetSeparableFilter - get separable convolution filter kernel images
FORTRAN SPECIFICATION
SUBROUTINE fglGetSeparableFilter( INTEGER*4 target,
INTEGER*4 format,
INTEGER*4 type,
CHARACTER*8 row,
CHARACTER*8 column,
CHARACTER*8 span )
PARAMETERS
target The separable filter to be retrieved. Must be GL_SEPARABLE_2D.
format Format of the output images. Must be one of GL_RED, GL_GREEN,
GL_BLUE, GL_ALPHA, GL_RGB, GL_BGR GL_RGBA, GL_BGRA, GL_ABGR_EXT,
GL_LUMINANCE, or GL_LUMINANCE_ALPHA.
type Data type of components in the output images. Symbolic constants
GL_UNSIGNED_BYTE, GL_BYTE, GL_BITMAP, GL_UNSIGNED_SHORT,
GL_SHORT, GL_UNSIGNED_INT, GL_INT, GL_FLOAT,
GL_UNSIGNED_BYTE_3_3_2, GL_UNSIGNED_BYTE_2_3_3_REV,
GL_UNSIGNED_SHORT_5_6_5, GL_UNSIGNED_SHORT_5_6_5_REV,
GL_UNSIGNED_SHORT_4_4_4_4, GL_UNSIGNED_SHORT_4_4_4_4_REV,
GL_UNSIGNED_SHORT_5_5_5_1, GL_UNSIGNED_SHORT_1_5_5_5_REV,
GL_UNSIGNED_INT_8_8_8_8, GL_UNSIGNED_INT_8_8_8_8_REV,
GL_UNSIGNED_INT_10_10_10_2, and GL_UNSIGNED_INT_2_10_10_10_REV
are accepted.
row Pointer to storage for the row filter image.
column Pointer to storage for the column filter image.
span Pointer to storage for the span filter image (currently unused).
DESCRIPTIONfglGetSeparableFilter returns the two one-dimensional filter kernel
images for the current separable 2D convolution filter. The row image is
placed in row and the column image is placed in column according to the
specifications in format and type. (In the current implementation, span
is not affected in any way.) No pixel transfer operations are performed
on the images, but the relevant pixel storage modes are applied.
Color components that are present in format but not included in the
internal format of the filters are returned as zero. The assignments of
internal color components to the components of format are as follows:
________________________________________
Internal Component Resulting Component
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fglGetSeparableFilter(3G) OpenGL Reference fglGetSeparableFilter(3G)
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Red Red
Green Green
Blue Blue
Alpha Alpha
Luminance Red
Intensity Red
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NOTESfglGetSeparableFilter is present only if GL_ARB_imaging is returned when
fglGetString is called with an argument of GL_EXTENSIONS.
GL_ABGR_EXT is valid only if the EXT_abgr extension is supported.
Non-separable 2D filters must be retrieved with fglGetConvolutionFilter.
ERRORS
GL_INVALID_ENUM is generated if target is not GL_SEPARABLE_2D.
GL_INVALID_ENUM is generated if format is not one of the allowable
values.
GL_INVALID_ENUM is generated if type is not one of the allowable values.
GL_INVALID_OPERATION is generated if fglGetSeparableFilter is executed
between the execution of fglBegin and the corresponding execution of
fglEnd.
GL_INVALID_OPERATION is generated if type is one of
GL_UNSIGNED_BYTE_3_3_2, GL_UNSIGNED_BYTE_2_3_3_REV,
GL_UNSIGNED_SHORT_5_6_5, or GL_UNSIGNED_SHORT_5_6_5_REV and format is not
GL_RGB.
GL_INVALID_OPERATION is generated if type is one of
GL_UNSIGNED_SHORT_4_4_4_4, GL_UNSIGNED_SHORT_4_4_4_4_REV,
GL_UNSIGNED_SHORT_5_5_5_1, GL_UNSIGNED_SHORT_1_5_5_5_REV,
GL_UNSIGNED_INT_8_8_8_8, GL_UNSIGNED_INT_8_8_8_8_REV,
GL_UNSIGNED_INT_10_10_10_2, or GL_UNSIGNED_INT_2_10_10_10_REV and format
is not GL_RGBA, GL_BGRA or GL_ABGR_EXT.
ASSOCIATED GETS
fglGetConvolutionParameter
SEE ALSO
fglGetConvolutionFilter, fglConvolutionParameter, fglSeparableFilter2D
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