1/*
2 * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
3 *           (C) 1999 Antti Koivisto (koivisto@kde.org)
4 * Copyright (C) 2003, 2006, 2007, 2009 Apple Inc. All rights reserved.
5 * Copyright (C) 2010, 2012 Google Inc. All rights reserved.
6 *
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Library General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * Library General Public License for more details.
16 *
17 * You should have received a copy of the GNU Library General Public License
18 * along with this library; see the file COPYING.LIB.  If not, write to
19 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
20 * Boston, MA 02110-1301, USA.
21 */
22
23#ifndef RenderLayerModelObject_h
24#define RenderLayerModelObject_h
25
26#include "RenderElement.h"
27
28namespace WebCore {
29
30class RenderLayer;
31
32class RenderLayerModelObject : public RenderElement {
33public:
34    virtual ~RenderLayerModelObject();
35
36    // Called by RenderObject::willBeDestroyed() and is the only way layers should ever be destroyed
37    void destroyLayer();
38
39    bool hasSelfPaintingLayer() const;
40    RenderLayer* layer() const { return m_layer.get(); }
41
42    virtual void styleWillChange(StyleDifference, const RenderStyle& newStyle) override;
43    virtual void styleDidChange(StyleDifference, const RenderStyle* oldStyle) override;
44    virtual void updateFromStyle() { }
45
46    virtual bool requiresLayer() const = 0;
47
48    // Returns true if the background is painted opaque in the given rect.
49    // The query rect is given in local coordinate system.
50    virtual bool backgroundIsKnownToBeOpaqueInRect(const LayoutRect&) const { return false; }
51
52protected:
53    RenderLayerModelObject(Element&, PassRef<RenderStyle>, unsigned baseTypeFlags);
54    RenderLayerModelObject(Document&, PassRef<RenderStyle>, unsigned baseTypeFlags);
55
56    void createLayer();
57
58    virtual void willBeDestroyed() override;
59
60private:
61    std::unique_ptr<RenderLayer> m_layer;
62
63    // Used to store state between styleWillChange and styleDidChange
64    static bool s_wasFloating;
65    static bool s_hadLayer;
66    static bool s_hadTransform;
67    static bool s_layerWasSelfPainting;
68};
69
70RENDER_OBJECT_TYPE_CASTS(RenderLayerModelObject, isRenderLayerModelObject())
71
72} // namespace WebCore
73
74#endif // RenderLayerModelObject_h
75