This patch is implementing a new default Catmull-Rom filter
to resize images.
Catmull-Rom is a special case of cubic interpolation with B=0 and
C=0.5 (in the Mitchell-Netravali formulation).
It provides slighlty sharper results than Mitchell with the same
performance.
Catmull-Rom is a better choice for a window manager as it prioritizes
sharpness, making small elements feel crisp.
This patch adds the RSaveTitledImage() function to the WRaster lib
to be able to save file on disk either as a PNG or a JPEG file.
Those two formats depends on optional external libs.
The function can take an optional title/comment which will
be save inside the file.
The WRaster lib and header versions are bumped.
The header "wraster.h" needs different behaviour depending on whether the
support for X Shared Memory extension was enabled or not; but the related
macro USE_XSHM is defined by WindowMaker's configure. After this header
have been installed, the macro is no more useable.
This patch makes the "wraster.h" a generated file, so it will be different
depending on USE_XSHM, but will not make use of the macro itself.
Signed-off-by: Christophe CURIS <christophe.curis@free.fr>
