LinGui: create custom widget that manages multiple overlay layers

composites the layers using per-pixel and global alpha values
the preview hud now uses this.

git-svn-id: svn://svn.handbrake.fr/HandBrake/trunk@2312 b64f7644-9d1e-0410-96f1-a4d463321fa5

1 files changed, 78 insertions, 0 deletions

diff --git a/gtk/src/composite_example.c b/gtk/src/composite_example.c
new file mode 100644
index 000000000..7918b3083
--- /dev/null
+++ b/gtk/src/composite_example.c
@@ -0,0 +1,78 @@
+#include <gtk/gtk.h>
+#include "ghbcompositor.h"
+
+// GhbCompositor example
+int
+main(gint argc, gchar *argv[])
+{
+    GtkWidget *window;
+    GtkWidget *blender;
+    GtkWidget *eb_bottom;
+    GtkWidget *eb_top1;
+    GtkWidget *eb_top2;
+    GtkWidget *eb_top3;
+    GtkWidget *bottom;
+    GtkWidget *top1;
+    GtkWidget *top2;
+    GtkWidget *top3;
+    GtkWidget *table;
+    GtkWidget *image;
+
+    gtk_init(&argc, &argv);
+
+    // Make the top level window
+    window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
+
+    // Only widgets that have a GdkDrawing area can be composited
+    // These would be GtkEventBox or GtkDrawingArea
+    // Create the widgets that will be composited
+    eb_bottom = gtk_event_box_new();
+    eb_top1 = gtk_event_box_new();
+    eb_top2 = gtk_event_box_new();
+    eb_top3 = gtk_event_box_new();
+
+    // Create the compositor
+    blender = ghb_compositor_new();
+
+    // Create an button to put on the bottom layer
+    bottom = gtk_button_new_with_label("Bottom");
+    image = gtk_image_new_from_stock("gtk-help", 6);
+    gtk_button_set_image(GTK_BUTTON(bottom), image);
+
+    // The button must be placed inside an event box since
+    // buttons do not have their own window.
+    gtk_container_add(GTK_CONTAINER(eb_bottom), bottom);
+
+    // Create the buttons that will be visible on the top layer
+    top1 = gtk_button_new_with_label("Top 1");
+    top2 = gtk_button_new_with_label("Top 2");
+    top3 = gtk_button_new_with_label("Top 3");
+
+    // The buttons must be placed inside an event box since
+    // buttons do not have their own window.
+    gtk_container_add(GTK_CONTAINER(eb_top1), top1);
+    gtk_container_add(GTK_CONTAINER(eb_top2), top2);
+    gtk_container_add(GTK_CONTAINER(eb_top3), top3);
+
+    // Create the table that will be the top layer
+    // Using a layout widget gives flexibility in the layout of the layer
+    table = gtk_table_new(3, 3, TRUE);
+    gtk_table_attach(GTK_TABLE(table), eb_top1, 0, 1, 0, 1, 0, 0, 0, 0);
+    gtk_table_attach(GTK_TABLE(table), eb_top2, 1, 2, 1, 2, 0, 0, 0, 0);
+    gtk_table_attach(GTK_TABLE(table), eb_top3, 2, 3, 2, 3, 0, 0, 0, 0);
+
+    // Add the blender to the main window.
+    gtk_container_add(GTK_CONTAINER(window), blender);
+
+    // Set the blenders zlist, with opacity values
+    // Bottom layer is opaque, top layer 60%
+    ghb_compositor_zlist_insert(GHB_COMPOSITOR(blender), eb_bottom, 1, 1);
+    ghb_compositor_zlist_insert(GHB_COMPOSITOR(blender), table, 2, 0.6);
+
+    // Start the show
+    gtk_widget_show_all(window);
+
+    gtk_main();
+    return 0;
+}
+