[gegl] examples: make hello-world.c not crash

[Daniel Sabo <daniels src gnome org>]

commit 73855efc25683a06bbd1ebfb4e288643b18c7b89
Author: Daniel Sabo <DanielSabo gmail com>
Date:   Sun Oct 13 11:58:37 2013 -0700

    examples: make hello-world.c not crash

 examples/hello-world.c |   60 +++++++++++++++++++++++------------------------
 1 files changed, 29 insertions(+), 31 deletions(-)
---
diff --git a/examples/hello-world.c b/examples/hello-world.c
index 6427947..1297aad 100644
--- a/examples/hello-world.c
+++ b/examples/hello-world.c
@@ -18,17 +18,21 @@ This is the graph we're going to construct:
 .-----------.
 | display   |
 `-----------'
-   |
-.-------.
-| over  |
-`-------'
-   |   \
-   |    \
-   |     \
-   |      |
-   |   .------.
-   |   | text |
-   |   `------'
+    |
+.--------.
+|  crop  |
+`--------'
+    |
+.--------.
+|  over  |
+`--------'
+    |   \
+    |    \
+    |     \
+    |      |
+    |   .------.
+    |   | text |
+    |   `------'
 .------------------.
 | fractal-explorer |
 `------------------'
@@ -37,6 +41,11 @@ This is the graph we're going to construct:
 
     /*< The image nodes representing operations we want to perform */
     GeglNode *display    = gegl_node_create_child (gegl, "gegl:display");
+    GeglNode *crop       = gegl_node_new_child (gegl,
+                                 "operation", "gegl:crop",
+                                 "width", 512.0,
+                                 "height", 384.0,
+                                  NULL);
     GeglNode *over       = gegl_node_new_child (gegl,
                                  "operation", "gegl:over",
                                  NULL);
@@ -47,11 +56,10 @@ This is the graph we're going to construct:
                                  NULL);
     GeglNode *mandelbrot = gegl_node_new_child (gegl,
                                 "operation", "gegl:fractal-explorer",
-                                "width", 512,
-                                "height", 384,
+                                "shiftx", -256.0,
                                 NULL);
 
-    gegl_node_link_many (mandelbrot, over, display, NULL);
+    gegl_node_link_many (mandelbrot, over, crop, display, NULL);
     gegl_node_connect_to (text, "output",  over, "aux");
 
     /* request that the save node is processed, all dependencies will
@@ -65,28 +73,18 @@ This is the graph we're going to construct:
         {
           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);
+          gdouble shiftx = INTERPOLATE(-256.0, -512.0);
+          gdouble shifty = INTERPOLATE(0.0,    -256.0);
+          gdouble zoom   = INTERPOLATE(300.0,   400.0);
 
-          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,
+          gegl_node_set (mandelbrot, "shiftx", shiftx,
+                                     "shifty", shifty,
+                                     "zoom", zoom,
                                      NULL);
-          g_sprintf (string, "%1.3f,%1.3f %1.3f×%1.3f",
-            xmin, ymin, xmax-xmin, ymax-ymin);
+          g_sprintf (string, "x=%1.3f y=%1.3f z=%1.3f", shiftx, shifty, zoom);
           gegl_node_set (text, "string", string, NULL);
           gegl_node_process (display);
         }