[gimp] app: add gimp_gegl_create_apply_buffer_node()

[Michael Natterer <mitch src gnome org>]

commit 5ad9b6fdd93a236d7c1147c2a4b42f496b1b2267
Author: Michael Natterer <mitch gimp org>
Date:   Sat Mar 24 14:54:36 2012 +0100

    app: add gimp_gegl_create_apply_buffer_node()
    
    which creates a graph that applies paint, and factor out
    gimp_gegl_add_buffer_source() which adds a buffer source with optional
    offset to a graph.

 app/gegl/gimp-gegl-nodes.c |  149 +++++++++++++++++++++++++++++++++++++++-----
 app/gegl/gimp-gegl-nodes.h |   27 +++++++--
 2 files changed, 156 insertions(+), 20 deletions(-)
---
diff --git a/app/gegl/gimp-gegl-nodes.c b/app/gegl/gimp-gegl-nodes.c
index bbae641..da6ec01 100644
--- a/app/gegl/gimp-gegl-nodes.c
+++ b/app/gegl/gimp-gegl-nodes.c
@@ -90,32 +90,151 @@ gimp_gegl_create_apply_opacity_node (GeglBuffer *mask,
                                       "operation", "gegl:opacity",
                                       "value",     opacity,
                                       NULL);
-  mask_source = gegl_node_new_child (node,
-                                     "operation", "gegl:buffer-source",
-                                     "buffer",    mask,
-                                     NULL);
+
+  mask_source = gimp_gegl_add_buffer_source (node, mask,
+                                             -mask_offset_x,
+                                             -mask_offset_y);
 
   gegl_node_connect_to (input,        "output",
                         opacity_node, "input");
+  gegl_node_connect_to (mask_source,  "output",
+                        opacity_node, "aux");
+  gegl_node_connect_to (opacity_node, "output",
+                        output,       "input");
+
+  return node;
+}
+
+GeglNode *
+gimp_gegl_create_apply_buffer_node (GeglBuffer           *buffer,
+                                    gint                  buffer_offset_x,
+                                    gint                  buffer_offset_y,
+                                    gint                  src_offset_x,
+                                    gint                  src_offset_y,
+                                    gint                  dest_offset_x,
+                                    gint                  dest_offset_y,
+                                    GeglBuffer           *mask,
+                                    gint                  mask_offset_x,
+                                    gint                  mask_offset_y,
+                                    gdouble               opacity,
+                                    GimpLayerModeEffects  mode)
+
+{
+  GeglNode *node;
+  GeglNode *input;
+  GeglNode *output;
+  GeglNode *buffer_source;
+  GeglNode *mask_source;
+  GeglNode *opacity_node;
+  GeglNode *mode_node;
 
-  if (mask_offset_x != 0 || mask_offset_y != 0)
+  g_return_val_if_fail (GEGL_IS_BUFFER (buffer), NULL);
+  g_return_val_if_fail (mask == NULL || GEGL_IS_BUFFER (mask), NULL);
+
+  node = gegl_node_new ();
+
+  buffer_source = gimp_gegl_add_buffer_source (node, buffer,
+                                               buffer_offset_x,
+                                               buffer_offset_y);
+
+  input = gegl_node_get_input_proxy (node, "input");
+
+  if (src_offset_x != 0 || src_offset_y != 0)
     {
-      GeglNode *translate = gegl_node_new_child (node,
-                                                 "operation", "gegl:translate",
-                                                 "x",         (gdouble) -mask_offset_x,
-                                                 "y",         (gdouble) -mask_offset_y,
-                                                 NULL);
+      GeglNode *translate =
+        gegl_node_new_child (node,
+                             "operation", "gegl:translate",
+                             "x",         (gdouble) src_offset_x,
+                             "y",         (gdouble) src_offset_y,
+                             NULL);
 
-      gegl_node_connect_to (mask_source,  "output",
-                            translate,    "input");
+      gegl_node_connect_to (input,     "output",
+                            translate, "input");
 
-      mask_source = translate;
+      input = translate;
     }
 
-  gegl_node_connect_to (mask_source,  "output",
-                        opacity_node, "aux");
+  output = gegl_node_get_output_proxy (node, "output");
+
+  if (dest_offset_x != 0 || dest_offset_y != 0)
+    {
+      GeglNode *translate =
+        gegl_node_new_child (node,
+                             "operation", "gegl:translate",
+                             "x",         (gdouble) dest_offset_x,
+                             "y",         (gdouble) dest_offset_y,
+                             NULL);
+
+      gegl_node_connect_to (translate, "output",
+                            output,    "input");
+
+      output = translate;
+    }
+
+  if (mask)
+    mask_source = gimp_gegl_add_buffer_source (node, mask,
+                                               mask_offset_x,
+                                               mask_offset_y);
+  else
+    mask_source = NULL;
+
+  opacity_node = gegl_node_new_child (node,
+                                      "operation", "gegl:opacity",
+                                      "value",     opacity,
+                                      NULL);
+
+  gegl_node_connect_to (buffer_source, "output",
+                        opacity_node,  "input");
+
+  if (mask_source)
+    gegl_node_connect_to (mask_source,   "output",
+                          opacity_node,  "aux");
+
+  mode_node = gegl_node_new_child (node,
+                                   "operation",
+                                   gimp_layer_mode_to_gegl_operation (mode),
+                                   NULL);
+
   gegl_node_connect_to (opacity_node, "output",
+                        mode_node,    "aux");
+  gegl_node_connect_to (input,        "output",
+                        mode_node,    "input");
+  gegl_node_connect_to (mode_node,    "output",
                         output,       "input");
 
   return node;
 }
+
+GeglNode *
+gimp_gegl_add_buffer_source (GeglNode   *parent,
+                             GeglBuffer *buffer,
+                             gint        offset_x,
+                             gint        offset_y)
+{
+  GeglNode *buffer_source;
+
+  g_return_val_if_fail (GEGL_IS_NODE (parent), NULL);
+  g_return_val_if_fail (GEGL_IS_BUFFER (buffer), NULL);
+
+  buffer_source = gegl_node_new_child (parent,
+                                       "operation", "gegl:buffer-source",
+                                       "buffer",    buffer,
+                                       NULL);
+
+  if (offset_x != 0 || offset_y != 0)
+    {
+      GeglNode *translate =
+        gegl_node_new_child (parent,
+                             "operation", "gegl:translate",
+                             "x",         (gdouble) offset_x,
+                             "y",         (gdouble) offset_y,
+                             NULL);
+
+      gegl_node_connect_to (buffer_source, "output",
+                            translate,     "input");
+
+      buffer_source = translate;
+    }
+
+  return buffer_source;
+}
diff --git a/app/gegl/gimp-gegl-nodes.h b/app/gegl/gimp-gegl-nodes.h
index 01cce1c..36396c7 100644
--- a/app/gegl/gimp-gegl-nodes.h
+++ b/app/gegl/gimp-gegl-nodes.h
@@ -22,12 +22,29 @@
 #define __GIMP_GEGL_NODES_H__
 
 
-GeglNode * gimp_gegl_create_flatten_node       (const GimpRGB *background);
-GeglNode * gimp_gegl_create_apply_opacity_node (GeglBuffer    *mask,
-                                                gdouble        opacity,
+GeglNode * gimp_gegl_create_flatten_node       (const GimpRGB        *background);
+GeglNode * gimp_gegl_create_apply_opacity_node (GeglBuffer           *mask,
+                                                gdouble               opacity,
                                                 /* offsets *into* the mask */
-                                                gint           mask_offset_x,
-                                                gint           mask_offset_y);
+                                                gint                  mask_offset_x,
+                                                gint                  mask_offset_y);
+GeglNode * gimp_gegl_create_apply_buffer_node  (GeglBuffer           *buffer,
+                                                gint                  buffer_offset_x,
+                                                gint                  buffer_offset_y,
+                                                gint                  src_offset_x,
+                                                gint                  src_offset_y,
+                                                gint                  dest_offset_x,
+                                                gint                  dest_offset_y,
+                                                GeglBuffer           *mask,
+                                                gint                  mask_offset_x,
+                                                gint                  mask_offset_y,
+                                                gdouble               opacity,
+                                                GimpLayerModeEffects  mode);
+
+GeglNode * gimp_gegl_add_buffer_source         (GeglNode             *parent,
+                                                GeglBuffer           *buffer,
+                                                gint                  offset_x,
+                                                gint                  offset_y);
 
 
 #endif /* __GIMP_GEGL_NODES_H__ */