GEGL-0.1.2

input

$ git clone git://git.gnome.org/babl
$ git clone git://git.gnome.org/gegl
$ ./configure  # or: ./autogen.sh if building from git
$ make
$ sudo make install
$ gcc hello-world.c `pkg-config --libs --cflags gegl` -o hello-world
#include "config.h"
#include <gegl.h>
#include <glib/gprintf.h>

gint
main (gint    argc,
      gchar **argv)
{
  g_thread_init (NULL);
  gegl_init (&argc, &argv);  /* initialize the GEGL library */

  {
    /* instantiate a graph */
    GeglNode *gegl = gegl_node_new ();

/*
This is the graph we're going to construct:

.-----------.
| display   |
`-----------'
   |
.-------.
| layer |
`-------'
   |   \
   |    \
   |     \
   |      |
   |   .------.
   |   | text |
   |   `------'
.------------------.
| fractal-explorer |
`------------------'

*/

    /*< The image nodes representing operations we want to perform */
    GeglNode *display    = gegl_node_create_child (gegl, "gegl:display");
    GeglNode *layer      = gegl_node_new_child (gegl,
                                 "operation", "gegl:layer",
                                 "x", 2.0,
                                 "y", 4.0,
                                 NULL);
    GeglNode *text       = gegl_node_new_child (gegl,
                                 "operation", "gegl:text",
                                 "size", 10.0,
                                 "color", gegl_color_new ("rgb(1.0,1.0,1.0)"),
                                 NULL);
    GeglNode *mandelbrot = gegl_node_new_child (gegl,
                                "operation", "gegl:fractal-explorer",
                                "width", 512,
                                "height", 384,
                                NULL);

    gegl_node_link_many (mandelbrot, layer, display, NULL);
    gegl_node_connect_to (text, "output",  layer, "aux");

    /* request that the save node is processed, all dependencies will
     * be processed as well
     */
    {
      gint frame;
      gint frames = 200;

      for (frame=0; frame<frames; frame++)
        {
          gchar string[512];
          gdouble t = frame * 1.0/frames;
          gdouble cx = -1.76;
          gdouble cy = 0.0;

#define INTERPOLATE(min,max) ((max)*(t)+(min)*(1.0-t))

          gdouble xmin = INTERPOLATE(  cx-0.02, cx-2.5);
          gdouble ymin = INTERPOLATE(  cy-0.02, cy-2.5);
          gdouble xmax = INTERPOLATE(  cx+0.02, cx+2.5);
          gdouble ymax = INTERPOLATE(  cy+0.02, cy+2.5);

          if (xmin<-3.0)
            xmin=-3.0;
          if (ymin<-3.0)
            ymin=-3.0;

          gegl_node_set (mandelbrot, "xmin", xmin,
                                     "ymin", ymin,
                                     "xmax", xmax,
                                     "ymax", ymax,
                                     NULL);
          g_sprintf (string, "%1.3f,%1.3f %1.3f×%1.3f",
            xmin, ymin, xmax-xmin, ymax-ymin);
          gegl_node_set (text, "string", string, NULL);
          gegl_node_process (display);
        }
    }

    /* free resources used by the graph and the nodes it owns */
    g_object_unref (gegl);
  }

  /* free resources globally used by GEGL */
  gegl_exit ();

  return 0;
}
$ gegl composition.xml -o composition.png
$ gegl -ui -d 5 composition.xml
$ cat input.png | gegl -o - -x "<gegl>
   <tree>
     <node class='invert'/>
     <node class='scale' x='0.5' y='0.5'/>
     <node class='png-load' path='-'/></tree></gegl>" > output.png
usage: /home/pippin/src/geglclean/gegl/bin/.libs/lt-gegl [options] <file | -- [op [op] ..]>

  Options:
     --help      this help information
     -h

     --file      read xml from named file
     -i

     --xml       use xml provided in next argument
     -x

     --dot       output a graphviz graph description
     --output    output generated image to named file
     -o          (file is saved in PNG or PPM format
                  depending on the file ending.)

     -p          (increment frame counters of various elements when
                  processing is done.)

     -X          output the XML that was read in

     --verbose   print diagnostics while running
      -v

All parameters following -- are considered ops to be chained together
into a small composition instead of using an xml file, this allows for
easy testing of filters. Be aware that the default value will be used
for all properties.
gegl-dist-root
 │
 │
 ├──gegl               core source of GEGL, library init/deinit,
 │   │
 │   ├──buffer         contains the implementation of GeglBuffer
 │   │                  - sparse (tiled)
 │   │                  - recursivly subbuffer extendable
 │   │                  - clipping rectangle (defaults to bounds when making
 │   │                    subbuffers)
 │   │                  - storage in any babl supported pixel format
 │   │                  - read/write rectangular region as linear buffer for
 │   │                    any babl supported pixel format.
 │   ├──graph          graph storage and manipulation code.
 │   ├──module         The code to load plug-ins located in a colon seperated
 │   │                 list of paths from the environment variable GEGL_PATH
 │   ├──operation      The GeglOperation base class, and subclasses that act
 │   │                 as baseclasses for implementeting different types of
 │   │                 operation plug-ins.
 │   ├──process        The code controlling data processing.
 │   └──property-types specialized classes/paramspecs for GeglOperation
 │                     properties.
 │
 ├──examples ⊙        hello-world and other example uses of the GEGL API.
 │
 ├──tests             various tests used to maintain stability when developing
 │                    GEGL.
 │
 ├──operations        Runtime loaded plug-ins for image processing operations.
 │   │
 │   ├──core ⊙        Basic operations tightly coupled with GEGL.
 │   ├──affine        Transforming operations (rotate/scale/translate)
 │   ├──generated ⊙   Operations generated from scripts (currently
 │   ├──external      Operations with external dependencies.
 │   ├──common ⊙      Other operations.
 │   └──workshop ⊙    Works in progress, (you must pass --enable-workshop
 │       │            when configurig to build these by default, you can enter
 │       │            the directory manually and type make && sudo make install
 │       │            as well.
 │       │
 │       ├──external  operations in the workshop with external dependencies.
 │       └──generated generated operations that are in the workshop.
 │
 │
 ├──docs              The GEGL website (this documentation), built for your
 │   │                the corresponding sourcetree with correct documentation
 │   │                etc.
 │   │
 │   └──gallery ⊙     A gallery of sample GEGL compositions, using the
 │       │            (not yet stabilized) XML format.
 │       │
 │       └──data      Image data used by the sample compositions.
 │
 ├──bin               gegl binary, for processing XML compositions to png files.
 │
 ├──bindings          bindings for using GEGL from other programming languages
 │                    not included in the tarball distribution but exist in
 │                    the git repository.
 │
 └──tools             some small utilities to help the build.

GEGL-0.1.2

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