[qpainter] Add getters for QImage; also make OptimizeImages a noop

The QPainter back end knows how to create a QImage from an image surface
while painting, so no need to copy the image.

gfx/cairo/cairo/src/cairo-qpainter-surface.cpp

@@ -1451,6 +1451,28 @@ cairo_qpainter_surface_get_qpainter (cairo_surface_t *surface)
     return qs->p;
 }
 
+QImage *
+cairo_qpainter_surface_get_qimage (cairo_surface_t *surface)
+{
+    cairo_qpainter_surface_t *qs = (cairo_qpainter_surface_t*) surface;
+
+    if (surface->type != CAIRO_SURFACE_TYPE_QPAINTER)
+        return NULL;
+
+    return qs->image;
+}
+
+cairo_surface_t *
+cairo_qpainter_surface_get_image (cairo_surface_t *surface)
+{
+    cairo_qpainter_surface_t *qs = (cairo_qpainter_surface_t*) surface;
+
+    if (surface->type != CAIRO_SURFACE_TYPE_QPAINTER)
+        return NULL;
+
+    return (cairo_surface_t*) qs->image_equiv;
+}
+
 /*
  * TODO:
  *

gfx/cairo/cairo/src/cairo-qpainter.h

@@ -42,6 +42,7 @@
 #if CAIRO_HAS_QPAINTER_SURFACE
 
 class QPainter;
+class QImage;
 
 CAIRO_BEGIN_DECLS
 
@@ -60,6 +61,12 @@ cairo_qpainter_surface_create_with_qpixmap (int width,
 cairo_public QPainter *
 cairo_qpainter_surface_get_qpainter (cairo_surface_t *surface);
 
+cairo_public cairo_surface_t *
+cairo_qpainter_surface_get_image (cairo_surface_t *surface);
+
+cairo_public QImage *
+cairo_qpainter_surface_get_qimage (cairo_surface_t *surface);
+
 CAIRO_END_DECLS
 
 #else /* CAIRO_HAS_QPAINTER_SURFACE */

gfx/thebes/public/gfxQPainterSurface.h

@@ -42,6 +42,7 @@
 #include "gfxImageSurface.h"
 
 class QPainter;
+class QImage;
 
 class THEBES_API gfxQPainterSurface : public gfxASurface {
 public:
@@ -55,6 +56,9 @@ public:
 
     QPainter *GetQPainter() { return mPainter; }
 
+    QImage *GetQImage();
+    already_AddRefed<gfxImageSurface> GetImageSurface();
+
 protected:
     QPainter *mPainter;
 };

gfx/thebes/public/gfxQtPlatform.h

@@ -60,6 +60,9 @@ public:
     already_AddRefed<gfxASurface> CreateOffscreenSurface(const gfxIntSize& size,
                                                          gfxASurface::gfxImageFormat imageFormat);
 
+    already_AddRefed<gfxASurface> OptimizeImage(gfxImageSurface *aSurface,
+                                                gfxASurface::gfxImageFormat format);
+
     nsresult GetFontList(const nsACString& aLangGroup,
                          const nsACString& aGenericFamily,
                          nsStringArray& aListOfFonts);

gfx/thebes/src/gfxQPainterSurface.cpp

@@ -36,6 +36,7 @@
  * ***** END LICENSE BLOCK ***** */
 
 #include "gfxQPainterSurface.h"
+#include "gfxImageSurface.h"
 
 #include "cairo-qpainter.h"
 
@@ -77,3 +78,29 @@ gfxQPainterSurface::gfxQPainterSurface(cairo_surface_t *csurf)
 gfxQPainterSurface::~gfxQPainterSurface()
 {
 }
+
+QImage *
+gfxQPainterSurface::GetQImage()
+{
+    if (!mSurfaceValid)
+        return nsnull;
+
+    return cairo_qpainter_surface_get_qimage(CairoSurface());
+}
+
+already_AddRefed<gfxImageSurface>
+gfxQPainterSurface::GetImageSurface()
+{
+    if (!mSurfaceValid)
+        return nsnull;
+
+    cairo_surface_t *isurf = cairo_qpainter_surface_get_image(CairoSurface());
+    if (!isurf)
+        return nsnull;
+
+    if (cairo_surface_get_type(isurf) == CAIRO_SURFACE_TYPE_IMAGE)
+        return nsnull;
+
+    nsRefPtr<gfxImageSurface> asurf = new gfxImageSurface(isurf);
+    return asurf.forget();
+}

gfx/thebes/src/gfxQtPlatform.cpp

@@ -126,6 +126,31 @@ gfxQtPlatform::CreateOffscreenSurface(const gfxIntSize& size,
     return newSurface.forget();
 }
 
+already_AddRefed<gfxASurface>
+gfxQtPlatform::OptimizeImage(gfxImageSurface *aSurface,
+                             gfxASurface::gfxImageFormat format)
+{
+    NS_ADDREF(aSurface);
+    return aSurface;
+
+#if 0
+    const gfxIntSize& surfaceSize = aSurface->GetSize();
+
+    nsRefPtr<gfxASurface> optSurface = CreateOffscreenSurface(surfaceSize, format);
+    if (!optSurface || optSurface->CairoStatus() != 0)
+        return nsnull;
+
+    gfxContext tmpCtx(optSurface);
+    tmpCtx.SetOperator(gfxContext::OPERATOR_SOURCE);
+    tmpCtx.SetSource(aSurface);
+    tmpCtx.Paint();
+
+    gfxASurface *ret = optSurface;
+    NS_ADDREF(ret);
+    return ret;
+#endif
+}
+
 nsresult
 gfxQtPlatform::GetFontList(const nsACString& aLangGroup,
                             const nsACString& aGenericFamily,