Advertise on this site
|
|
|
glGetSeparableFilter — get separable convolution filter kernel images
void glGetSeparableFilter( | GLenum | target, |
| GLenum | format, | |
| GLenum | type, | |
| GLvoid * | row, | |
| GLvoid * | column, | |
| GLvoid * | span); |
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_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.
rowPointer to storage for the row filter image.
columnPointer to storage for the column filter image.
spanPointer to storage for the span filter image (currently unused).
glGetSeparableFilter 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.
If a non-zero named buffer object is bound to the GL_PIXEL_PACK_BUFFER target
(see glBindBuffer) while a separable convolution filter is
requested, row, column, and span are treated as a byte offset into the buffer object's data store.
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 |
|---|---|
| Red | Red |
| Green | Green |
| Blue | Blue |
| Alpha | Alpha |
| Luminance | Red |
| Intensity | Red |
glGetSeparableFilter is present only if ARB_imaging is returned when glGetString
is called with an argument of GL_EXTENSIONS.
Non-separable 2D filters must be retrieved with glGetConvolutionFilter.
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 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 neither GL_RGBA nor GL_BGRA.
GL_INVALID_OPERATION is generated if a non-zero buffer object name is bound to the
GL_PIXEL_PACK_BUFFER target and the buffer object's data store is currently mapped.
GL_INVALID_OPERATION is generated if a non-zero buffer object name is bound to the
GL_PIXEL_PACK_BUFFER target and the data would be packed to the buffer
object such that the memory writes required would exceed the data store size.
GL_INVALID_OPERATION is generated if a non-zero buffer object name is bound to the
GL_PIXEL_PACK_BUFFER target and row or column is not evenly divisible
into the number of bytes needed to store in memory a datum indicated by type.
GL_INVALID_OPERATION is generated if glGetSeparableFilter is executed
between the execution of glBegin and the corresponding
execution of glEnd.
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/.