give WindowProxy its own map/unmap signals so that other things can track map/unmap...

[ardour.git] / libs / canvas / canvas / image.h

diff --git a/libs/canvas/canvas/image.h b/libs/canvas/canvas/image.h
index b4227ac09d09de8ca4bfb0fd8270438ce0d83a23..292de567230b8faea47ec1d5a4cc77a0050a5e89 100644 (file)
--- a/libs/canvas/canvas/image.h
+++ b/libs/canvas/canvas/image.h
@@ -23,42 +23,80 @@
 #include <boost/shared_ptr.hpp>
 #include <boost/shared_array.hpp>
 
+#include "canvas/visibility.h"
 #include "canvas/item.h"
 
+typedef void (*ImageReleaseCallback)(uint8_t *d, void *arg);
+
 namespace ArdourCanvas {
 
-class Image : public Item
+
+class LIBCANVAS_API Image : public Item
 {
 public:
-    Image (Group *, Cairo::Format, int width, int height);
-    
+    Image (Canvas *, Cairo::Format, int width, int height);
+    Image (Item*, Cairo::Format, int width, int height);
+
     struct Data {
-       Data (boost::shared_array<uint8_t> d, int w, int h, int s, Cairo::Format fmt)
+       Data (uint8_t *d, int w, int h, int s, Cairo::Format fmt)
                : data (d)
                , width (w)
                , height (h)
                , stride (s)
                , format (fmt)
+               , destroy_callback(NULL)
+               , destroy_arg(NULL)
        {}
 
-       boost::shared_array<uint8_t> data;
+       virtual ~Data () {
+               if (destroy_callback) {
+                       destroy_callback(data, destroy_arg);
+               } else {
+                       free(data);
+               }
+       }
+
+       uint8_t* data;
        int width;
        int height;
        int stride;
        Cairo::Format format;
+       ImageReleaseCallback  destroy_callback;
+       void* destroy_arg;
     };
 
-    boost::shared_ptr<Data> get_image ();
+    /**
+     * Returns a shared_ptr to a Data object that can be used to
+     * write image data to. The Data object will contain a pointer
+     * to the buffer, along with image properties that may be
+     * useful during the data writing.
+     *
+     * Can be called from any thread BUT ..
+     *
+     * ... to avoid collisions with Image deletion, some synchronization method
+     * may be required or the use of shared_ptr<Image> or similar.
+     */
+    boost::shared_ptr<Data> get_image (bool allocate_data = true);
+
+
+    /**
+     * Queues a Data object to be used to redraw this Image item
+     * at the earliest possible opportunity.
+     *
+     * May be called from any thread BUT ...
+     *
+     * ... to avoid collisions with Image deletion, some synchronization method
+     * may be required or the use of shared_ptr<Image> or similar.
+     */
     void put_image (boost::shared_ptr<Data>);
 
     void render (Rect const &, Cairo::RefPtr<Cairo::Context>) const;
     void compute_bounding_box () const;
-    
+
 private:
     Cairo::Format            _format;
     int                      _width;
     int                      _height;
-    int                      _data;
     mutable boost::shared_ptr<Data>  _current;
     boost::shared_ptr<Data>  _pending;
     mutable bool             _need_render;