5 files changed, 51 insertions, 27 deletions

diff --git a/src/mcompositemanager.cpp b/src/mcompositemanager.cpp
index 4901b4b..668407d 100644
--- a/src/mcompositemanager.cpp
+++ b/src/mcompositemanager.cpp
@@ -1818,7 +1818,12 @@ void MCompositeManagerPrivate::mapEvent(XMapEvent *e)
         else
             item->saveBackingStore(true);
         item->setVisible(true);
-        item->fadeIn();
+        // TODO: don't show the animation if the window is not stacked on top
+        const XWMHints &h = pc->getWMHints();
+        if (!(h.flags & StateHint) || h.initial_state != IconicState)
+            item->fadeIn();
+        else
+            item->setNewlyMapped(false);
         goto stack_and_return;
     }
 
@@ -1836,10 +1841,14 @@ void MCompositeManagerPrivate::mapEvent(XMapEvent *e)
             qDebug() << "Composition overhead (new pixmap):"
                      << overhead_measure.elapsed();
 #endif
-        if (item->isAppWindow())
+        const XWMHints &h = pc->getWMHints();
+        if ((!(h.flags & StateHint) || h.initial_state != IconicState)
+            && item->isAppWindow())
             item->fadeIn();
-        else
+        else {
             item->setVisible(true);
+            item->setNewlyMapped(false);
+        }
         
         // the current decorated window got mapped
         if (e->window == MDecoratorFrame::instance()->managedWindow() &&
diff --git a/src/mcompositescene.cpp b/src/mcompositescene.cpp
index 36cb017..a2a437c 100644
--- a/src/mcompositescene.cpp
+++ b/src/mcompositescene.cpp
@@ -98,21 +98,41 @@ void MCompositeScene::setupOverlay(Window window, const QRect &geom,
 
 void MCompositeScene::drawItems(QPainter *painter, int numItems, QGraphicsItem *items[], const QStyleOptionGraphicsItem options[], QWidget *widget)
 {
-    for (int i = 0; i < numItems; ++i) {
-        MCompositeWindow *window = (MCompositeWindow *) items[i];
+    QRegion visible(sceneRect().toRect());
+    QList<QGraphicsItem*> to_paint;
+    QList<QStyleOptionGraphicsItem> paint_opts;
+    // visibility is determined from top to bottom
+    for (int i = numItems - 1; i >= 0; --i) {
+        MCompositeWindow *cw = (MCompositeWindow *) items[i];
         
-        // Redraw only textures which don't have opaque textures above it
-        if (((i < numItems - 1) 
-             && (items[i+1]->sceneMatrix().mapRect(items[i]->boundingRect()) ==
-                 items[i]->boundingRect())
-             && (!((MCompositeWindow *)items[i+1])->propertyCache()->hasAlpha())
-             && (((MCompositeWindow *)items[i+1])->opacity() == 1.0))
-            || window->isIconified()) 
-            continue;
+        if (visible.isEmpty())
+            // nothing below is visible anymore
+            break;
+
+        // FIXME: this region is always the same as the window's shape,
+        // some transformations would be needed...
+        QRegion r(cw->sceneMatrix().map(cw->propertyCache()->shapeRegion()));
         
+        // transitioning window can be smaller than shapeRegion(), so paint
+        // all transitioning windows
+        if (cw->isWindowTransitioning() || visible.intersects(r)) {
+            to_paint.prepend(cw);
+            paint_opts.prepend(options[i]);
+        }
+
+        // subtract opaque regions
+        if (!cw->isWindowTransitioning()
+            && !cw->propertyCache()->hasAlpha() && cw->opacity() == 1.0)
+            visible -= r;
+    }
+    // paint from bottom to top so that blending works
+    while (!to_paint.isEmpty()) {
+        // TODO: paint only the intersected region (glScissor?)
+        MCompositeWindow *cw = (MCompositeWindow*)to_paint.takeFirst();
         painter->save();
-        painter->setMatrix(items[i]->sceneMatrix(), true);
-        items[i]->paint(painter, &options[i], widget);
+        painter->setMatrix(cw->sceneMatrix(), true);
+        QStyleOptionGraphicsItem opts = paint_opts.takeFirst();
+        cw->paint(painter, &opts, widget);
         painter->restore();
     }
 }
diff --git a/src/mtexturepixmapitem_p.cpp b/src/mtexturepixmapitem_p.cpp
index 223b442..4343a82 100644
--- a/src/mtexturepixmapitem_p.cpp
+++ b/src/mtexturepixmapitem_p.cpp
@@ -255,12 +255,7 @@ void MTexturePixmapPrivate::damageTracking(bool enabled)
 
 void MTexturePixmapPrivate::saveBackingStore(bool renew)
 {
-    XWindowAttributes a;
-    if (!XGetWindowAttributes(QX11Info::display(), item->window(), &a)) {
-        qWarning("%s: invalid window 0x%lx", __func__, item->window());
-        return;
-    }
-    if (a.map_state != IsViewable)
+    if (item->propertyCache()->is_valid && !item->propertyCache()->isMapped())
         return;
 
     if (windowp)
diff --git a/src/mwindowpropertycache.cpp b/src/mwindowpropertycache.cpp
index a11f82c..764d896 100644
--- a/src/mwindowpropertycache.cpp
+++ b/src/mwindowpropertycache.cpp
@@ -218,19 +218,19 @@ bool MWindowPropertyCache::hasAlpha()
     return has_alpha ? true : false;
 }
 
-const QRegion MWindowPropertyCache::shapeRegion()
+const QRegion &MWindowPropertyCache::shapeRegion()
 {
     if (shape_rects_valid) {
         if (shape_region.isEmpty())
-            return QRegion(realGeometry());
-        else
-            return shape_region;
+            shape_region = QRegion(realGeometry());
+        return shape_region;
     }
     xcb_shape_get_rectangles_reply_t *r;
     r = xcb_shape_get_rectangles_reply(xcb_conn, xcb_shape_rects_cookie, 0);
     if (!r) {
         shape_rects_valid = true;
-        return QRegion(realGeometry());
+        shape_region = QRegion(realGeometry());
+        return shape_region;
     }
     xcb_rectangle_iterator_t i;
     i = xcb_shape_get_rectangles_rectangles_iterator(r);
diff --git a/src/mwindowpropertycache.h b/src/mwindowpropertycache.h
index 5f049a0..e75a5d0 100644
--- a/src/mwindowpropertycache.h
+++ b/src/mwindowpropertycache.h
@@ -80,7 +80,7 @@ public:
         }
         return real_geom;
     }
-    const QRegion shapeRegion();
+    const QRegion &shapeRegion();
     void shapeRefresh() {
         if (!shape_rects_valid)
             shapeRegion();