1 files changed, 19 insertions, 8 deletions

diff --git a/src/plugins/platforms/xlib/qxlibwindowsurface.cpp b/src/plugins/platforms/xlib/qxlibwindowsurface.cpp
index 513f10dc6a..a917f452e8 100644
--- a/src/plugins/platforms/xlib/qxlibwindowsurface.cpp
+++ b/src/plugins/platforms/xlib/qxlibwindowsurface.cpp
@@ -49,6 +49,8 @@
 #include "qxlibscreen.h"
 #include "qxlibdisplay.h"
 
+#include "qpainter.h"
+
 # include <sys/ipc.h>
 # include <sys/shm.h>
 # include <X11/extensions/XShm.h>
@@ -80,20 +82,19 @@ void QXlibShmImageInfo::destroy()
 
 void QXlibWindowSurface::resizeShmImage(int width, int height)
 {
+    QXlibScreen *screen = QXlibScreen::testLiteScreenForWidget(window());
+    QXlibWindow *win = static_cast<QXlibWindow*>(window()->platformWindow());
 
 #ifdef DONT_USE_MIT_SHM
-    shm_img = QImage(width, height, QImage::Format_RGB32);
+    shm_img = QImage(width, height, win->format());
 #else
 
-    QXlibScreen *screen = QXlibScreen::testLiteScreenForWidget(window());
     if (image_info)
         image_info->destroy();
     else
         image_info = new QXlibShmImageInfo(screen->display()->nativeDisplay());
 
-    Visual *visual = screen->defaultVisual();
-
-    XImage *image = XShmCreateImage (screen->display()->nativeDisplay(), visual, 24, ZPixmap, 0,
+    XImage *image = XShmCreateImage (screen->display()->nativeDisplay(), win->visual(), win->depth(), ZPixmap, 0,
                                      &image_info->shminfo, width, height);
 
 
@@ -109,7 +110,7 @@ void QXlibWindowSurface::resizeShmImage(int width, int height)
 
     Q_ASSERT(shm_attach_status == True);
 
-    shm_img = QImage( (uchar*) image->data, image->width, image->height, image->bytes_per_line, QImage::Format_RGB32 );
+    shm_img = QImage( (uchar*) image->data, image->width, image->height, image->bytes_per_line, win->format() );
 #endif
     painted = false;
 }
@@ -160,11 +161,11 @@ void QXlibWindowSurface::flush(QWidget *widget, const QRegion &region, const QPo
 #ifdef DONT_USE_MIT_SHM
     // just convert the image every time...
     if (!shm_img.isNull()) {
-        Visual *visual = DefaultVisual(screen->display(), screen->xScreenNumber());
+        QXlibWindow *win = static_cast<QXlibWindow*>(window()->platformWindow());
 
         QImage image = shm_img;
         //img.convertToFormat(
-        XImage *xi = XCreateImage(screen->display(), visual, 24, ZPixmap,
+        XImage *xi = XCreateImage(screen->display(), win->visual(), win->depth(), ZPixmap,
                                   0, (char *) image.scanLine(0), image.width(), image.height(),
                                   32, image.bytesPerLine());
 
@@ -214,6 +215,16 @@ void QXlibWindowSurface::beginPaint(const QRegion &region)
 {
     Q_UNUSED(region);
     resizeBuffer(size());
+
+    if (shm_img.hasAlphaChannel()) {
+        QPainter p(&shm_img);
+        p.setCompositionMode(QPainter::CompositionMode_Source);
+        const QVector<QRect> rects = region.rects();
+        const QColor blank = Qt::transparent;
+        for (QVector<QRect>::const_iterator it = rects.begin(); it != rects.end(); ++it) {
+            p.fillRect(*it, blank);
+        }
+    }
 }
 
 void QXlibWindowSurface::endPaint(const QRegion &region)