[blitter] Work on tst_QPixmap::clear()

By default QPixmap may not hasAlphaChannel(), only if setMask()
or fill() with a transparent color is called a QPixmap will
hasAlphaChannel().

Make the QBlittablePlatformPixmap remember if there is an alpha
channel, pass this as parameter in createBlittable to make it
clear that this is required and not optional.

Update the DirectFB plugin to handle this parameter to create a
RGB32 or ARGB Surface depending on the alpha value, also only use
PreMultiplied alpha when using ARGB. Separate the two constructors
for the QDirectFbBlitter to either adopt a DirectFB Surface or to
create one.

Change-Id: I8abf82408ecd2d075fc6f241ace8be2a34ac56e7
Reviewed-by: Jørgen Lind <jorgen.lind@nokia.com>

2 files changed, 30 insertions, 13 deletions

diff --git a/src/plugins/platforms/directfb/qdirectfbblitter.cpp b/src/plugins/platforms/directfb/qdirectfbblitter.cpp
index a4da2d8142..7df96c10c7 100644
--- a/src/plugins/platforms/directfb/qdirectfbblitter.cpp
+++ b/src/plugins/platforms/directfb/qdirectfbblitter.cpp
@@ -54,22 +54,33 @@ QDirectFbBlitter::QDirectFbBlitter(const QSize &rect, IDirectFBSurface *surface)
                                                           |QBlittable::SourceOverPixmapCapability
                                                           |QBlittable::SourceOverScaledPixmapCapability))
 {
-    if (surface) {
-        m_surface = surface;
-    } else {
-        DFBSurfaceDescription surfaceDesc;
-        memset(&surfaceDesc,0,sizeof(DFBSurfaceDescription));
-        surfaceDesc.width = rect.width();
-        surfaceDesc.height = rect.height();
+    m_surface = surface;
+}
+
+QDirectFbBlitter::QDirectFbBlitter(const QSize &rect, bool alpha)
+    : QBlittable(rect, QBlittable::Capabilities(QBlittable::SolidRectCapability
+                                                |QBlittable::SourcePixmapCapability
+                                                |QBlittable::SourceOverPixmapCapability
+                                                |QBlittable::SourceOverScaledPixmapCapability))
+{
+    DFBSurfaceDescription surfaceDesc;
+    memset(&surfaceDesc,0,sizeof(DFBSurfaceDescription));
+    surfaceDesc.width = rect.width();
+    surfaceDesc.height = rect.height();
+
+    if (alpha) {
         surfaceDesc.caps = DSCAPS_PREMULTIPLIED;
         surfaceDesc.pixelformat = DSPF_ARGB;
         surfaceDesc.flags = DFBSurfaceDescriptionFlags(DSDESC_WIDTH | DSDESC_HEIGHT | DSDESC_CAPS | DSDESC_PIXELFORMAT);
-
-        IDirectFB *dfb = QDirectFbConvenience::dfbInterface();
-        dfb->CreateSurface(dfb,&surfaceDesc, &m_surface);
-        m_surface->Clear(m_surface,0,0,0,0);
+    } else {
+        surfaceDesc.flags = DFBSurfaceDescriptionFlags(DSDESC_WIDTH | DSDESC_HEIGHT | DSDESC_PIXELFORMAT);
+        surfaceDesc.pixelformat = DSPF_RGB32;
     }
 
+
+    IDirectFB *dfb = QDirectFbConvenience::dfbInterface();
+    dfb->CreateSurface(dfb , &surfaceDesc, &m_surface);
+    m_surface->Clear(m_surface, 0, 0, 0, 0);
 }
 
 QDirectFbBlitter::~QDirectFbBlitter()
diff --git a/src/plugins/platforms/directfb/qdirectfbblitter.h b/src/plugins/platforms/directfb/qdirectfbblitter.h
index 2dcb2be07a..e9a77c2707 100644
--- a/src/plugins/platforms/directfb/qdirectfbblitter.h
+++ b/src/plugins/platforms/directfb/qdirectfbblitter.h
@@ -51,7 +51,8 @@
 class QDirectFbBlitter : public QBlittable
 {
 public:
-    QDirectFbBlitter(const QSize &size, IDirectFBSurface *surface = 0);
+    QDirectFbBlitter(const QSize &size, IDirectFBSurface *surface);
+    QDirectFbBlitter(const QSize &size, bool alpha);
     virtual ~QDirectFbBlitter();
 
     virtual void fillRect(const QRectF &rect, const QColor &color);
@@ -70,7 +71,12 @@ protected:
 class QDirectFbBlitterPlatformPixmap : public QBlittablePlatformPixmap
 {
 public:
-    QBlittable *createBlittable(const QSize &size) const { return new QDirectFbBlitter(size); }
+    QBlittable *createBlittable(const QSize &size, bool alpha) const;
 };
 
+inline QBlittable *QDirectFbBlitterPlatformPixmap::createBlittable(const QSize& size, bool alpha) const
+{
+    return new QDirectFbBlitter(size, alpha);
+}
+
 #endif // QDIRECTFBBLITTER_H