cookbook: Added layout introduction and "stacking actors" recipe

Expanded the layout introduction and added a recipe about
stacking actors using ClutterBinLayout, with two examples.

doc/cookbook/examples/.gitignore

@@ -3,3 +3,5 @@
 /textures-reflection
 /textures-split-go
 /textures-sub-texture
+/layouts-stacking
+/layouts-stacking-diff-sized-actors

doc/cookbook/examples/Makefile.am

@@ -8,6 +8,8 @@ noinst_PROGRAMS = \
 	textures-reflection	\
 	textures-split-go	\
 	textures-sub-texture	\
+	layouts-stacking \
+	layouts-stacking-diff-sized-actors	\
 	$(NULL)
 
 INCLUDES = \
@@ -29,8 +31,10 @@ AM_CFLAGS = \
 
 AM_LDFLAGS = $(CLUTTER_LIBS)
 
-animations_rotating_SOURCES   = animations-rotating.c
-text_shadow_SOURCES           = text-shadow.c
-textures_reflection_SOURCES   = textures-reflection.c
-textures_split_go_SOURCES     = textures-split-go.c
-textures_sub_texture_SOURCES  = textures-sub-texture.c
+animations_rotating_SOURCES                = animations-rotating.c
+text_shadow_SOURCES                        = text-shadow.c
+textures_reflection_SOURCES                = textures-reflection.c
+textures_split_go_SOURCES                  = textures-split-go.c
+textures_sub_texture_SOURCES               = textures-sub-texture.c
+layouts_stacking_SOURCES                   = layouts-stacking.c
+layouts_stacking_diff_sized_actors_SOURCES = layouts-stacking-diff-sized-actors.c

doc/cookbook/examples/layouts-stacking-diff-sized-actors.c

@@ -0,0 +1,78 @@
+#include <clutter/clutter.h>
+
+static const ClutterColor dark_grey = { 0x66, 0x66, 0x66, 0xff };
+static const ClutterColor light_grey = { 0xcc, 0xcc, 0xcc, 0xff };
+
+int
+main (int argc, char *argv[])
+{
+  ClutterActor *stage;
+  ClutterLayoutManager *layout;
+  ClutterActor *box;
+  ClutterActor *rect1, *rect2;
+  guint align_x, align_y, diff_x, diff_y;
+
+  clutter_init (&argc, &argv);
+
+  stage = clutter_stage_get_default ();
+  clutter_actor_set_size (stage, 400, 400);
+
+  layout = clutter_bin_layout_new (CLUTTER_BIN_ALIGNMENT_START,
+                                   CLUTTER_BIN_ALIGNMENT_START);
+
+  box = clutter_box_new (layout);
+
+  rect1 = clutter_rectangle_new_with_color (&dark_grey);
+  clutter_actor_set_size (rect1, 400, 200);
+
+  rect2 = clutter_rectangle_new_with_color (&light_grey);
+  clutter_actor_set_size (rect2, 200, 400);
+
+  clutter_container_add (CLUTTER_CONTAINER (box),
+                         rect1,
+                         rect2,
+                         NULL);
+
+  /*
+   * 2 = CLUTTER_BIN_ALIGNMENT_START
+   * 3 = CLUTTER_BIN_ALIGNMENT_END
+   * 4 = CLUTTER_BIN_ALIGNMENT_CENTER
+   */
+  for (align_x = 2; align_x < 5; align_x++)
+    {
+      for (align_y = 2; align_y < 5; align_y++)
+        {
+          diff_x = align_x - 1;
+          if (align_x == 3)
+            diff_x = 3;
+          else if (align_x == 4)
+            diff_x = 2;
+
+          diff_y = align_y - 1;
+          if (align_y == 3)
+            diff_y = 3;
+          else if (align_y == 4)
+            diff_y = 2;
+
+          ClutterColor *color = clutter_color_new (255 - diff_x * 50,
+                                                   100 + diff_y * 50,
+                                                   0,
+                                                   255);
+          ClutterActor *rect = clutter_rectangle_new_with_color (color);
+          clutter_actor_set_size (rect, 100, 100);
+          clutter_bin_layout_set_alignment (CLUTTER_BIN_LAYOUT (layout),
+                                            rect,
+                                            align_x,
+                                            align_y);
+          clutter_container_add_actor (CLUTTER_CONTAINER (box), rect);
+        }
+    }
+
+  clutter_container_add_actor (CLUTTER_CONTAINER (stage), box);
+
+  clutter_actor_show (stage);
+
+  clutter_main ();
+
+  return 0;
+}

doc/cookbook/examples/layouts-stacking.c

@@ -0,0 +1,80 @@
+/*
+ * Display multiple rotated copies of an image on top of each other
+ *
+ * Invoke with the path to a file to load a custom image
+ */
+#include <clutter/clutter.h>
+
+#define STAGE_SIDE 512
+
+static const ClutterColor box_color = { 0x33, 0x33, 0x55, 0xff };
+
+int
+main (int argc, char *argv[])
+{
+  gchar *filename = TESTS_DATA_DIR "/redhand.png";
+
+  if (argc > 1)
+    filename = argv[1];
+
+  ClutterLayoutManager *layout;
+  ClutterActor *box;
+  ClutterActor *stage;
+  ClutterActor *texture;
+  CoglHandle *cogl_texture;
+  GError *error = NULL;
+  gfloat width;
+
+  clutter_init (&argc, &argv);
+
+  stage = clutter_stage_get_default ();
+  clutter_actor_set_size (stage, STAGE_SIDE, STAGE_SIDE);
+
+  layout = clutter_bin_layout_new (CLUTTER_BIN_ALIGNMENT_CENTER,
+                                   CLUTTER_BIN_ALIGNMENT_CENTER);
+
+  box = clutter_box_new (layout);
+  clutter_box_set_color (CLUTTER_BOX (box), &box_color);
+
+  texture = clutter_texture_new_from_file (filename, &error);
+
+  if (error != NULL)
+    g_error ("Error loading file %s; message was:\n%s",
+             filename,
+             error->message);
+
+  /*
+   * get a reference to the underlying Cogl texture
+   * for copying onto each Clutter texture placed into the layout
+   */
+  cogl_texture = clutter_texture_get_cogl_texture (CLUTTER_TEXTURE (texture));
+
+  /*
+   * add gradually turning and shrinking textures,
+   * smallest one last; each actor ends up on top
+   * of the one added just before it
+   */
+  for (width = STAGE_SIDE * 0.75; width >= STAGE_SIDE * 0.0625; width -= STAGE_SIDE * 0.0625)
+    {
+      ClutterActor *texture_copy = clutter_texture_new ();
+      clutter_texture_set_cogl_texture (CLUTTER_TEXTURE (texture_copy),
+                                        cogl_texture);
+      clutter_texture_set_keep_aspect_ratio (CLUTTER_TEXTURE (texture_copy),
+                                             TRUE);
+      clutter_actor_set_z_rotation_from_gravity (texture_copy,
+                                                 (gfloat)(width * 0.5) - (STAGE_SIDE * 0.03125),
+                                                 CLUTTER_GRAVITY_CENTER);
+      clutter_actor_set_width (texture_copy, width);
+      clutter_container_add_actor (CLUTTER_CONTAINER (box), texture_copy);
+    }
+
+  clutter_actor_add_constraint (box, clutter_align_constraint_new (stage, CLUTTER_ALIGN_X_AXIS, 0.5));
+  clutter_actor_add_constraint (box, clutter_align_constraint_new (stage, CLUTTER_ALIGN_Y_AXIS, 0.5));
+  clutter_container_add_actor (CLUTTER_CONTAINER (stage), box);
+
+  clutter_actor_show (stage);
+
+  clutter_main ();
+
+  return 0;
+}