fixed software cursor rendering when the widget under the cursor is redrawn

also check if the cursor exists before checking if it is dirty when
considering an early exit from QFbScreen::doRedraw()

2 files changed, 3 insertions, 2 deletions

diff --git a/src/plugins/platforms/fb_base/fb_base.cpp b/src/plugins/platforms/fb_base/fb_base.cpp
index 0463a60..5004a5a 100644
--- a/src/plugins/platforms/fb_base/fb_base.cpp
+++ b/src/plugins/platforms/fb_base/fb_base.cpp
@@ -187,7 +187,7 @@ QRegion QFbScreen::doRedraw()
         QRect lastCursor = cursor->dirtyRect();
         repaintRegion += lastCursor;
     }
-    if (repaintRegion.isEmpty() && !cursor->isDirty()) {
+    if (repaintRegion.isEmpty() && (!cursor || !cursor->isDirty())) {
         return touchedRegion;
     }
 
@@ -239,7 +239,7 @@ QRegion QFbScreen::doRedraw()
     }
 
     QRect cursorRect;
-    if (cursor && cursor->isDirty()) {
+    if (cursor && (cursor->isDirty() || repaintRegion.intersects(cursor->lastPainted()))) {
         cursorRect = cursor->drawCursor(*compositePainter);
         touchedRegion += cursorRect;
     }
diff --git a/src/plugins/platforms/fb_base/fb_base.h b/src/plugins/platforms/fb_base/fb_base.h
index f1dd574..124dde0 100644
--- a/src/plugins/platforms/fb_base/fb_base.h
+++ b/src/plugins/platforms/fb_base/fb_base.h
@@ -32,6 +32,7 @@ public:
     virtual void setDirty() { dirty = true; screen->setDirty(QRect()); }
     virtual bool isDirty() { return dirty; }
     virtual bool isOnScreen() { return onScreen; }
+    virtual QRect lastPainted() { return prevRect; }
 
 protected:
     QGraphicsSystemCursorImage * graphic;