Paging is slowly becoming better, but still susceptible to race conditions
[rodin/chimara.git] / libchimara / pager.c
index e00daf97710c8f25e5ea4409e58618d3bd864291..c88ab63630c3918478e7c1d75027af4a85307175 100644 (file)
@@ -6,12 +6,8 @@
  and return the distance between the pager and the end of the buffer in buffer
  coordinates */
 static void
-move_pager_and_get_scroll_distance(GtkTextView *textview, gint *view_height, gint *scroll_distance)
+move_pager_and_get_scroll_distance(GtkTextView *textview, gint *view_height, gint *scroll_distance, gboolean move )
 {
-       while( gtk_events_pending() ) {
-               gtk_main_iteration();
-       }
-
        GdkRectangle pagerpos, endpos, visiblerect;
        GtkTextIter oldpager, newpager, end;
        GtkTextBuffer *buffer = gtk_text_view_get_buffer(textview);
@@ -19,10 +15,16 @@ move_pager_and_get_scroll_distance(GtkTextView *textview, gint *view_height, gin
        
        /* Get an iter at the lower right corner of the visible part of the buffer */
        gtk_text_view_get_visible_rect(textview, &visiblerect);
-       gtk_text_view_get_iter_at_location(textview, &newpager, visiblerect.x + visiblerect.width, visiblerect.y + visiblerect.height);
+       gtk_text_view_get_iter_at_location(
+               textview,
+               &newpager,
+               visiblerect.x + visiblerect.width,
+               visiblerect.y + visiblerect.height
+       );
        gtk_text_buffer_get_iter_at_mark(buffer, &oldpager, pager);
        
-       gtk_text_buffer_move_mark(buffer, pager, &newpager);
+       if(move)
+               gtk_text_buffer_move_mark(buffer, pager, &newpager);
 
        /* Get the buffer coordinates of the pager and the end iter */
        gtk_text_buffer_get_end_iter(buffer, &end);
@@ -30,8 +32,8 @@ move_pager_and_get_scroll_distance(GtkTextView *textview, gint *view_height, gin
        gtk_text_view_get_iter_location(textview, &newpager, &pagerpos);
        gtk_text_view_get_iter_location(textview, &end, &endpos);
 
-       /*g_printerr("View height = %d\n", visiblerect.height);
-       g_printerr("End - Pager = %d\n", endpos.y - pagerpos.y);*/
+       g_printerr("View height = %d\n", visiblerect.height);
+       g_printerr("End - Pager = %d\n", endpos.y - pagerpos.y);
        
        *view_height = visiblerect.height;
        *scroll_distance = endpos.y - pagerpos.y;
@@ -41,6 +43,7 @@ move_pager_and_get_scroll_distance(GtkTextView *textview, gint *view_height, gin
 static void
 start_paging(winid_t win)
 {
+       printf("Start paging\n");
        win->currently_paging = TRUE;
        g_signal_handler_unblock(win->widget, win->pager_expose_handler);
        g_signal_handler_unblock(win->widget, win->pager_keypress_handler);
@@ -50,53 +53,66 @@ start_paging(winid_t win)
 static void
 stop_paging(winid_t win)
 {
+       printf("Stop paging\n");
        win->currently_paging = FALSE;
        g_signal_handler_block(win->widget, win->pager_expose_handler);
        g_signal_handler_block(win->widget, win->pager_keypress_handler);
 }
 
-/* Update the pager position after new text is inserted in the buffer and the
-text view has calculated where it is */
-void
-pager_after_size_allocate(GtkTextView *view, GtkAllocation *allocation, winid_t win)
+/* Check whether paging should be done. This function is called inside the 
+ * idle handler, after the textview has finished updating. */
+gboolean
+pager_check(gpointer data)
 {
-       while(gtk_events_pending())
-               gtk_main_iteration();
-       
+
+       printf("pager check (idle)...\n");
+       winid_t win = (winid_t) data;
+
+
        /* Move the pager to the last visible character in the buffer */
        gint view_height, scroll_distance;
-       move_pager_and_get_scroll_distance( GTK_TEXT_VIEW(win->widget), &view_height, &scroll_distance );
+       move_pager_and_get_scroll_distance( GTK_TEXT_VIEW(win->widget), &view_height, &scroll_distance, FALSE );
+
+       gdk_threads_enter();
 
        if(view_height <= 1)
                /* Paging is unusable when window is too small */
-               return;
+               return FALSE;
        
        if(!win->currently_paging) {
                if(scroll_distance > view_height) {
                        start_paging(win);
                        /* Seriously... */
+                       /* COMPAT: */
+#if GTK_CHECK_VERSION(2,14,0)
                        gdk_window_invalidate_rect(gtk_widget_get_window(win->widget), NULL, TRUE);
+#else
+                       gdk_window_invalidate_rect(win->widget->window, NULL, TRUE);
+#endif
                }
                else if(scroll_distance > 0) {
-                       GtkTextBuffer *buffer = gtk_text_view_get_buffer(GTK_TEXT_VIEW(win->widget));
-                       gtk_text_view_scroll_mark_onscreen(GTK_TEXT_VIEW(win->widget), gtk_text_buffer_get_mark(buffer, "end_position"));
-                       while( gtk_events_pending() ) {
-                               gtk_main_iteration();
+                       if(win->input_request_type != INPUT_REQUEST_NONE) {
+                               GtkTextBuffer *buffer = gtk_text_view_get_buffer(GTK_TEXT_VIEW(win->widget));
+                               GtkTextMark *end = gtk_text_buffer_get_mark(buffer, "end_position");
+
+                               gtk_text_view_scroll_mark_onscreen(GTK_TEXT_VIEW(win->widget), end);
                        }
                }
        }
+       gdk_threads_leave();
+
+       /* Returning FALSE to prevent this function from being called multiple times */
+       return FALSE;
 }
 
+/* When the user scrolls up in a textbuffer, start paging. */
 void
 pager_after_adjustment_changed(GtkAdjustment *adj, winid_t win)
 {
-       while(gtk_events_pending())
-               gtk_main_iteration();
-       
        /* Move the pager, etc. */
        gint scroll_distance, view_height;
-       move_pager_and_get_scroll_distance( GTK_TEXT_VIEW(win->widget), &view_height, &scroll_distance );
-       
+       move_pager_and_get_scroll_distance( GTK_TEXT_VIEW(win->widget), &view_height, &scroll_distance, TRUE );
+
        if(scroll_distance > 0 && !win->currently_paging)
                start_paging(win);
        else if(scroll_distance == 0 && win->currently_paging)
@@ -157,3 +173,48 @@ pager_on_expose(GtkTextView *textview, GdkEventExpose *event, winid_t win)
 
        return FALSE; /* Propagate event further */
 }
+
+gboolean
+pager_after_expose_event(GtkTextView *textview, GdkEventExpose *event, winid_t win)
+{
+       printf("pager check (expose)...\n");
+       g_idle_add(pager_check, win);
+
+//     /* Move the pager to the last visible character in the buffer */
+//     gint view_height, scroll_distance;
+//     move_pager_and_get_scroll_distance( GTK_TEXT_VIEW(win->widget), &view_height, &scroll_distance, FALSE );
+//
+//     if(view_height <= 1)
+//             /* Paging is unusable when window is too small */
+//             return FALSE;
+//     
+//     if(!win->currently_paging) {
+//             if(scroll_distance > view_height) {
+//                     start_paging(win);
+//                     /* Seriously... */
+//                     /* COMPAT: */
+//#if GTK_CHECK_VERSION(2,14,0)
+//                     gdk_window_invalidate_rect(gtk_widget_get_window(win->widget), NULL, TRUE);
+//#else
+//                     gdk_window_invalidate_rect(win->widget->window, NULL, TRUE);
+//#endif
+//             }
+//             else if(scroll_distance > 0) {
+//                     if(win->input_request_type != INPUT_REQUEST_NONE) {
+//                             GtkTextBuffer *buffer = gtk_text_view_get_buffer(GTK_TEXT_VIEW(win->widget));
+//                             GtkTextMark *end = gtk_text_buffer_get_mark(buffer, "end_position");
+//
+//                             gtk_text_view_scroll_mark_onscreen(GTK_TEXT_VIEW(win->widget), end);
+//                     }
+//             }
+//     }
+
+       return FALSE;
+}
+
+void
+pager_after_size_request(GtkTextView *textview, GtkRequisition *requisition, winid_t win)
+{
+       printf("pager check (size request)...\n");
+       g_idle_add(pager_check, win);
+}