glSeparableFilter2D man page on Darwin

Man page or keyword search:  
man Server   23457 pages
apropos Keyword Search (all sections)
Output format
Darwin logo
[printable version]

GLSEPARABLEFILTER2D(3G)				       GLSEPARABLEFILTER2D(3G)

NAME
       glSeparableFilter2D  -  define  a separable two-dimensional convolution
       filter

C SPECIFICATION
       void glSeparableFilter2D( GLenum target,
				 GLenum internalformat,
				 GLsizei width,
				 GLsizei height,
				 GLenum format,
				 GLenum type,
				 const GLvoid *row,
				 const GLvoid *column )

PARAMETERS
       target	       Must be GL_SEPARABLE_2D.

       internalformat  The internal  of the convolution	 filter	 kernel.   The
		       allowable  values  are  GL_ALPHA, GL_ALPHA4, GL_ALPHA8,
		       GL_ALPHA12,  GL_ALPHA16,	 GL_LUMINANCE,	GL_LUMINANCE4,
		       GL_LUMINANCE8,	   GL_LUMINANCE12,     GL_LUMINANCE16,
		       GL_LUMINANCE_ALPHA,		 GL_LUMINANCE4_ALPHA4,
		       GL_LUMINANCE6_ALPHA2,		 GL_LUMINANCE8_ALPHA8,
		       GL_LUMINANCE12_ALPHA4,	       GL_LUMINANCE12_ALPHA12,
		       GL_LUMINANCE16_ALPHA16,	 GL_INTENSITY,	GL_INTENSITY4,
		       GL_INTENSITY8,	  GL_INTENSITY12,      GL_INTENSITY16,
		       GL_R3_G3_B2,   GL_RGB,	GL_RGB4,   GL_RGB5,   GL_RGB8,
		       GL_RGB10,  GL_RGB12,   GL_RGB16,	  GL_RGBA,   GL_RGBA2,
		       GL_RGBA4, GL_RGB5_A1, GL_RGBA8, GL_RGB10_A2, GL_RGBA12,
		       or GL_RGBA16.

       width	       The number of elements in the pixel array referenced by
		       row.   (This  is the width of the separable filter ker‐
		       nel.)

       height	       The number of elements in the pixel array referenced by
		       column.	 (This	is  the height of the separable filter
		       kernel.)

       format	       The  of the pixel data in row and column.   The	allow‐
		       able  values  are  GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA,
		       GL_RGB,	 GL_BGR,   GL_RGBA,   GL_BGRA,	 GL_INTENSITY,
		       GL_LUMINANCE, and GL_LUMINANCE_ALPHA.

       type	       The type of the pixel data in row and column.  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 a one-dimensional array of pixel  data  that
		       is processed to build the row filter kernel.

       column	       Pointer	to  a one-dimensional array of pixel data that
		       is processed to build the column filter kernel.

DESCRIPTION
       glSeparableFilter2D builds a two-dimensional separable convolution fil‐
       ter kernel from two arrays of pixels.

       The  pixel  arrays specified by (width, format, type, row) and (height,
       format, type, column) are processed just as if they had been passed  to
       glDrawPixels, but processing stops after the final expansion to RGBA is
       completed.

       Next, the R, G, B, and A components of all pixels in  both  arrays  are
       scaled  by the four separable 2D GL_CONVOLUTION_FILTER_SCALE parameters
       and biased by the four separable 2D GL_CONVOLUTION_FILTER_BIAS  parame‐
       ters.  (The scale and bias parameters are set by glConvolutionParameter
       using	 the	 GL_SEPARABLE_2D     target	and	the	 names
       GL_CONVOLUTION_FILTER_SCALE and GL_CONVOLUTION_FILTER_BIAS.  The param‐
       eters themselves are vectors of four values that are  applied  to  red,
       green,  blue, and alpha, in that order.)	 The R, G, B, and A values are
       not clamped to [0,1] at any time during this process.

       Each pixel is then converted to the internal  specified by internalfor‐
       mat.  This conversion simply maps the component values of the pixel (R,
       G, B, and A) to the values included in the internal  (red, green, blue,
       alpha, luminance, and intensity).  The mapping is as follows:

       ────────────────────────────────────────────────────────────────────────
       Internal Format	    Red	  Green	  Blue	 Alpha	 Luminance   Intensity
       ────────────────────────────────────────────────────────────────────────
       GL_LUMINANCE					     R
       GL_LUMINANCE_ALPHA			   A	     R
       GL_INTENSITY							 R
       GL_RGB		     R	    G	   B
       GL_RGBA		     R	    G	   B	   A
       ────────────────────────────────────────────────────────────────────────

       The  red, green, blue, alpha, luminance, and/or intensity components of
       the resulting pixels are stored in floating-point rather	 than  integer
       They  form  two one-dimensional filter kernel images.  The row image is
       indexed by coordinate i starting at zero and increasing	from  left  to
       right.	Each  location	in  the row image is derived from element i of
       row.  The column image is indexed by coordinate j starting at zero  and
       increasing  from	 bottom	 to top.  Each location in the column image is
       derived from element j of column.

       Note that after a convolution is performed, the resulting color	compo‐
       nents	  are	   also	     scaled	by     their	 corresponding
       GL_POST_CONVOLUTION_c_SCALE parameters and biased by their  correspond‐
       ing  GL_POST_CONVOLUTION_c_BIAS parameters (where c takes on the values
       RED,  GREEN,  BLUE,  and	 ALPHA).   These   parameters	are   set   by
       glPixelTransfer.

NOTES
       glSeparableFilter2D  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 GL_SEPARABLE_2D.

       GL_INVALID_ENUM is generated if internalformat is not one of the allow‐
       able values.

       GL_INVALID_VALUE	 is  generated	if  width is less than zero or greater
       than the maximum supported value.   This	 value	may  be	 queried  with
       glGetConvolutionParameter   using   target   GL_SEPARABLE_2D  and  name
       GL_MAX_CONVOLUTION_WIDTH.

       GL_INVALID_VALUE is generated if height is less than  zero  or  greater
       than  the  maximum  supported  value.   This  value may be queried with
       glGetConvolutionParameter  using	 target	  GL_SEPARABLE_2D   and	  name
       GL_MAX_CONVOLUTION_HEIGHT.

       GL_INVALID_ENUM is generated if format is not one of the allowable val‐
       ues.

       GL_INVALID_ENUM is generated if type is not one of the  allowable  val‐
       ues.

       GL_INVALID_OPERATION  is	 generated  if glSeparableFilter2D is executed
       between the execution of glBegin and  the  corresponding	 execution  of
       glEnd.

       GL_INVALID_OPERATION    is    generated	  if	height	 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    height    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  for‐
       mat is neither GL_RGBA nor GL_BGRA.

ASSOCIATED GETS
       glGetConvolutionParameter, glGetSeparableFilter

SEE ALSO
       glConvolutionFilter1D,  glConvolutionFilter2D,  glConvolutionParameter,
       glPixelTransfer

						       GLSEPARABLEFILTER2D(3G)
[top]

List of man pages available for Darwin

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Tweet
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
....................................................................
Vote for polarhome
Free Shell Accounts :: the biggest list on the net