[gimp] app: add gimp_motion_buffer_pop_event_queue() and use it

[Michael Natterer <mitch src gnome org>]

commit bb3eac557d6a52fc1e21c7cd143eaba99f06f7d9
Author: Michael Natterer <mitch gimp org>
Date:   Sun Apr 17 20:20:18 2011 +0200

    app: add gimp_motion_buffer_pop_event_queue() and use it
    
    instead of accessing and removing the queue's first element menually.

 app/display/gimpdisplayshell-tool-events.c |   12 +++++-------
 app/display/gimpmotionbuffer.c             |   18 +++++++++++++++++-
 app/display/gimpmotionbuffer.h             |   12 +++++++-----
 3 files changed, 29 insertions(+), 13 deletions(-)
---
diff --git a/app/display/gimpdisplayshell-tool-events.c b/app/display/gimpdisplayshell-tool-events.c
index 9deceb2..58c5426 100644
--- a/app/display/gimpdisplayshell-tool-events.c
+++ b/app/display/gimpdisplayshell-tool-events.c
@@ -977,17 +977,15 @@ gimp_display_shell_canvas_tool_events (GtkWidget        *canvas,
                                                FALSE,
                                                time))
               {
-                /* then update the tool. */
-                GimpCoords *buf_coords = &g_array_index (shell->motion_buffer->event_queue,
-                                                         GimpCoords, 0);
+                GimpCoords buf_coords;
+
+                gimp_motion_buffer_pop_event_queue (shell->motion_buffer,
+                                                    &buf_coords);
 
                 tool_manager_oper_update_active (gimp,
-                                                 buf_coords, state,
+                                                 &buf_coords, state,
                                                  shell->proximity,
                                                  display);
-
-                /* remove used event */
-                g_array_remove_index (shell->motion_buffer->event_queue, 0);
               }
 
             gimp_motion_buffer_push_event_history (shell->motion_buffer,
diff --git a/app/display/gimpmotionbuffer.c b/app/display/gimpmotionbuffer.c
index 8ecb21d..ab137e4 100644
--- a/app/display/gimpmotionbuffer.c
+++ b/app/display/gimpmotionbuffer.c
@@ -385,14 +385,30 @@ gimp_motion_buffer_eval_event (GimpMotionBuffer *buffer,
 
 void
 gimp_motion_buffer_push_event_history (GimpMotionBuffer *buffer,
-                                       GimpCoords       *coords)
+                                       const GimpCoords *coords)
 {
+  g_return_if_fail (GIMP_IS_MOTION_BUFFER (buffer));
+  g_return_if_fail (coords != NULL);
+
   if (buffer->event_history->len == 4)
     g_array_remove_index (buffer->event_history, 0);
 
   g_array_append_val (buffer->event_history, *coords);
 }
 
+void
+gimp_motion_buffer_pop_event_queue (GimpMotionBuffer *buffer,
+                                    GimpCoords       *coords)
+{
+  g_return_if_fail (GIMP_IS_MOTION_BUFFER (buffer));
+  g_return_if_fail (coords != NULL);
+  g_return_if_fail (buffer->event_queue->len > 0);
+
+  *coords = g_array_index (buffer->event_queue, GimpCoords, 0);
+
+  g_array_remove_index (buffer->event_queue, 0);
+}
+
 
 /*  private functions  */
 
diff --git a/app/display/gimpmotionbuffer.h b/app/display/gimpmotionbuffer.h
index ded8b93..c8c4683 100644
--- a/app/display/gimpmotionbuffer.h
+++ b/app/display/gimpmotionbuffer.h
@@ -68,18 +68,20 @@ struct _GimpMotionBufferClass
 };
 
 
-GType              gimp_motion_buffer_get_type (void) G_GNUC_CONST;
+GType              gimp_motion_buffer_get_type   (void) G_GNUC_CONST;
 
-GimpMotionBuffer * gimp_motion_buffer_new      (void);
+GimpMotionBuffer * gimp_motion_buffer_new        (void);
 
-gboolean           gimp_motion_buffer_eval_event (GimpMotionBuffer *buffer,
+gboolean   gimp_motion_buffer_eval_event         (GimpMotionBuffer *buffer,
                                                   gdouble           scale_x,
                                                   gdouble           scale_y,
                                                   GimpCoords       *coords,
                                                   gboolean          event_fill,
                                                   guint32           time);
-void               gimp_motion_buffer_push_event_history (GimpMotionBuffer *buffer,
-                                                          GimpCoords       *coords);
+void       gimp_motion_buffer_push_event_history (GimpMotionBuffer *buffer,
+                                                  const GimpCoords *coords);
+void       gimp_motion_buffer_pop_event_queue    (GimpMotionBuffer *buffer,
+                                                  GimpCoords       *coords);
 
 
 #endif /* __GIMP_MOTION_BUFFER_H__ */