Timeline: Redraw only marching ants on timer tick (fix #1537)

src/app/ui/timeline/timeline.cpp

@@ -209,6 +209,7 @@ Timeline::Timeline()
   , m_confPopup(NULL)
   , m_clipboard_timer(100, this)
   , m_offset_count(0)
+  , m_redrawMarchingAntsOnly(false)
   , m_scroll(false)
   , m_fromTimeline(false)
 {
@@ -518,18 +519,23 @@ bool Timeline::onProcessMessage(Message* msg)
           &clipboard_document,
           &clipboard_range);
 
-        if (isVisible() && m_document && clipboard_document == m_document) {
+        if (isVisible() &&
+            m_document &&
+            m_document == clipboard_document) {
           // Set offset to make selection-movement effect
           if (m_offset_count < 7)
             m_offset_count++;
           else
             m_offset_count = 0;
+
+          bool redrawOnlyMarchingAnts = getUpdateRegion().isEmpty();
+          invalidateRect(gfx::Rect(getRangeBounds(clipboard_range)).offset(origin()));
+          if (redrawOnlyMarchingAnts)
+            m_redrawMarchingAntsOnly = true;
         }
         else if (m_clipboard_timer.isRunning()) {
           m_clipboard_timer.stop();
         }
-
-        invalidate();
       }
       break;
 
@@ -1236,6 +1242,12 @@ bool Timeline::onProcessMessage(Message* msg)
   return Widget::onProcessMessage(msg);
 }
 
+void Timeline::onInvalidateRegion(const gfx::Region& region)
+{
+  Widget::onInvalidateRegion(region);
+  m_redrawMarchingAntsOnly = false;
+}
+
 void Timeline::onSizeHint(SizeHintEvent& ev)
 {
   // This doesn't matter, the AniEditor'll use the entire screen anyway.
@@ -1270,6 +1282,12 @@ void Timeline::onPaint(ui::PaintEvent& ev)
     // the background thread is making a backup.
     const DocumentReader documentReader(m_document, 250);
 
+    if (m_redrawMarchingAntsOnly) {
+      drawClipboardRange(g);
+      m_redrawMarchingAntsOnly = false;
+      return;
+    }
+
     layer_t layer, firstLayer, lastLayer;
     frame_t frame, firstFrame, lastFrame;
 

src/app/ui/timeline/timeline.h

@@ -114,6 +114,7 @@ namespace app {
 
   protected:
     bool onProcessMessage(ui::Message* msg) override;
+    void onInvalidateRegion(const gfx::Region& region) override;
     void onSizeHint(ui::SizeHintEvent& ev) override;
     void onResize(ui::ResizeEvent& ev) override;
     void onPaint(ui::PaintEvent& ev) override;
@@ -352,6 +353,7 @@ namespace app {
     // TODO merge this with the marching ants of the sprite editor (ui::Editor)
     ui::Timer m_clipboard_timer;
     int m_offset_count;
+    bool m_redrawMarchingAntsOnly;
 
     bool m_scroll;   // True if the drag-and-drop operation is a scroll operation.
     bool m_copy;     // True if the drag-and-drop operation is a copy.

src/ui/widget.cpp

@@ -1044,6 +1044,8 @@ void Widget::setTransparent(bool transparent)
 
 void Widget::invalidate()
 {
+  // TODO we should use invalidateRect(bounds()) here.
+
   if (isVisible()) {
     m_updateRegion.clear();
     getDrawableRegion(m_updateRegion, kCutTopWindows);