WidgetBackingStoreCairo.cpp [plain text]
#include "config.h"
#include "WidgetBackingStore.h"
#include "CairoUtilities.h"
#include "RefPtrCairo.h"
#include <cairo/cairo.h>
#if PLATFORM(GTK)
#include "GtkVersioning.h"
#endif
namespace WebCore {
static PassRefPtr<cairo_surface_t> createSurfaceForBackingStore(PlatformWidget widget, const IntSize& size)
{
#if PLATFORM(GTK)
return gdk_window_create_similar_surface(gtk_widget_get_window(widget),
CAIRO_CONTENT_COLOR_ALPHA,
size.width(), size.height());
#else
return adoptRef(cairo_image_surface_create(CAIRO_FORMAT_ARGB32, size.width(), size.height()));
#endif
}
class WidgetBackingStorePrivate {
WTF_MAKE_NONCOPYABLE(WidgetBackingStorePrivate);
WTF_MAKE_FAST_ALLOCATED;
public:
RefPtr<cairo_surface_t> m_surface;
RefPtr<cairo_surface_t> m_scrollSurface;
static PassOwnPtr<WidgetBackingStorePrivate> create(PlatformWidget widget, const IntSize& size)
{
return adoptPtr(new WidgetBackingStorePrivate(widget, size));
}
private:
WidgetBackingStorePrivate(PlatformWidget widget, const IntSize& size)
: m_surface(createSurfaceForBackingStore(widget, size))
, m_scrollSurface(createSurfaceForBackingStore(widget, size))
{
}
};
PassOwnPtr<WidgetBackingStore> WidgetBackingStore::create(PlatformWidget widget, const IntSize& size)
{
return adoptPtr(new WidgetBackingStore(widget, size));
}
WidgetBackingStore::WidgetBackingStore(PlatformWidget widget, const IntSize& size)
: m_private(WidgetBackingStorePrivate::create(widget, size))
, m_size(size)
{
}
WidgetBackingStore::~WidgetBackingStore()
{
}
cairo_surface_t* WidgetBackingStore::cairoSurface()
{
return m_private->m_surface.get();
}
void WidgetBackingStore::scroll(const IntRect& scrollRect, const IntSize& scrollOffset)
{
IntRect targetRect(scrollRect);
targetRect.move(scrollOffset);
targetRect.shiftMaxXEdgeTo(targetRect.maxX() - scrollOffset.width());
targetRect.shiftMaxYEdgeTo(targetRect.maxY() - scrollOffset.height());
if (targetRect.isEmpty())
return;
copyRectFromOneSurfaceToAnother(m_private->m_surface.get(), m_private->m_scrollSurface.get(),
scrollOffset, targetRect);
copyRectFromOneSurfaceToAnother(m_private->m_scrollSurface.get(), m_private->m_surface.get(),
IntSize(), targetRect);
}
}