QtOpenGL/plugins/platformsupport: use new QRegion::begin()/end() instead of rect()

Saves e.g. ~900b and ~2900b in text size in QtOpenGL and
XcbQpa libs, resp., on optimized GCC 5.3 Linux AMD64 builds.

Change-Id: Id904689164ca32df41118a23747c70048d8e6604
Reviewed-by: Lars Knoll <lars.knoll@theqtcompany.com>

2 files changed, 11 insertions, 14 deletions

diff --git a/src/plugins/platforms/windows/qwindowsbackingstore.cpp b/src/plugins/platforms/windows/qwindowsbackingstore.cpp
index 7123ed826d..ea7a5e3c75 100644
--- a/src/plugins/platforms/windows/qwindowsbackingstore.cpp
+++ b/src/plugins/platforms/windows/qwindowsbackingstore.cpp
@@ -175,7 +175,7 @@ void QWindowsBackingStore::resize(const QSize &size, const QRegion &region)
             staticRegion &= QRect(0, 0, newimg.width(), newimg.height());
             QPainter painter(&newimg);
             painter.setCompositionMode(QPainter::CompositionMode_Source);
-            foreach (const QRect &rect, staticRegion.rects())
+            for (const QRect &rect : staticRegion)
                 painter.drawImage(rect, oldimg, rect);
         }
 
@@ -190,10 +190,9 @@ bool QWindowsBackingStore::scroll(const QRegion &area, int dx, int dy)
     if (m_image.isNull() || m_image->image().isNull())
         return false;
 
-    const QVector<QRect> rects = area.rects();
     const QPoint offset(dx, dy);
-    for (int i = 0; i < rects.size(); ++i)
-        qt_scrollRectInImage(m_image->image(), rects.at(i), offset);
+    for (const QRect &rect : area)
+        qt_scrollRectInImage(m_image->image(), rect, offset);
 
     return true;
 }
@@ -207,7 +206,7 @@ void QWindowsBackingStore::beginPaint(const QRegion &region)
         QPainter p(&m_image->image());
         p.setCompositionMode(QPainter::CompositionMode_Source);
         const QColor blank = Qt::transparent;
-        foreach (const QRect &r, region.rects())
+        for (const QRect &r : region)
             p.fillRect(r, blank);
     }
 }
diff --git a/src/plugins/platforms/windows/qwindowswindow.cpp b/src/plugins/platforms/windows/qwindowswindow.cpp
index d9a7586096..4a665c15ad 100644
--- a/src/plugins/platforms/windows/qwindowswindow.cpp
+++ b/src/plugins/platforms/windows/qwindowswindow.cpp
@@ -2047,15 +2047,13 @@ static inline void addRectToWinRegion(const QRect &rect, HRGN *winRegion)
 
 static HRGN qRegionToWinRegion(const QRegion &region)
 {
-    const QVector<QRect> rects = region.rects();
-    if (rects.isEmpty())
-        return NULL;
-    const int rectCount = rects.size();
-    if (rectCount == 1)
-        return createRectRegion(region.boundingRect());
-    HRGN hRegion = createRectRegion(rects.front());
-    for (int i = 1; i < rectCount; ++i)
-        addRectToWinRegion(rects.at(i), &hRegion);
+    auto it = region.begin();
+    const auto end = region.end();
+    if (it == end)
+        return nullptr;
+    HRGN hRegion = createRectRegion(*it);
+    while (++it != end)
+        addRectToWinRegion(*it, &hRegion);
     return hRegion;
 }