Re: [Gegl-developer] problem drawing a path

[Ville Sokk <ville sokk gmail com>]

On Sat, Feb 2, 2013 at 7:08 PM, Torsten Mohr <tmohr s netic de> wrote:
> Hello,
>
> I'm trying to draw a path based on an XML example, i try to draw a line in a
> 320x320 gray image:
>
> <?xml version='1.0' encoding='UTF-8'?>
> <gegl>
>   <node operation='gegl:path'>
>     <params>
>       <param name='fill'>rgb(1.0, 0.0, 0.0)</param>
>       <param name='stroke'>rgb(1.0, 1.0, 1.0)</param>
>       <param name='stroke-width'>15.0</param>
>       <param name='stroke-opacity'>0.5</param>
>       <param name='stroke-hardness'>1.0</param>
>       <param name='d'>M100 0 L 100 320</param>
>     </params>
>   </node>
>   <node operation='gegl:crop'>
>     <params>
>       <param name='width'>320.000000</param>
>       <param name='height'>320.000000</param>
>     </params>
>   </node>
>   <node operation='gegl:color'>
>     <params>
>       <param name='value'>rgb(0.5, 0.5, 0.5)</param>
>     </params>
>   </node>
> </gegl>
>
> gegl file.xml -o test.png
>
> I can't reproduce what i get as a result, i can see a gray background, but i
> can't see no line.  Also, there are two stripes with just  Alpha shown at the
> top and the bottom of the image.
>
> I did not find any example XML that uses gegl:path, also i did not find
> information about the format of the path, i assumed SVG format.
>
> Can anybody explain the output i see from my XML?
>
> Is there an example that uses gegl:path?
>
> I did not find any explicitly described way to create an image in memory, are
> the last two nodes the preferred way to create a gray image of 320x320?
>
>
> Thanks for any hints
> Torsten

In bin/gegl.c there's a #define called DEFAULT_COMPOSITION that uses
gegl:fill-path. That's an example of how vectors are described.