cc/base/region.h

// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CC_BASE_REGION_H_
#define CC_BASE_REGION_H_

#include <string>

#include "base/logging.h"
#include "base/memory/scoped_ptr.h"
#include "cc/base/cc_export.h"
#include "third_party/skia/include/core/SkRegion.h"
#include "ui/gfx/rect.h"
#include "ui/gfx/skia_util.h"

namespace base {
class Value;
}

namespace cc {

class CC_EXPORT Region {
 public:
  Region();
  Region(const Region& region);
  Region(gfx::Rect rect);  // NOLINT(runtime/explicit)
  ~Region();

  const Region& operator=(gfx::Rect rect);
  const Region& operator=(const Region& region);

  void Swap(Region* region);
  void Clear();
  bool IsEmpty() const;
  int GetRegionComplexity() const;

  bool Contains(gfx::Point point) const;
  bool Contains(gfx::Rect rect) const;
  bool Contains(const Region& region) const;

  bool Intersects(gfx::Rect rect) const;
  bool Intersects(const Region& region) const;

  void Subtract(gfx::Rect rect);
  void Subtract(const Region& region);
  void Union(gfx::Rect rect);
  void Union(const Region& region);
  void Intersect(gfx::Rect rect);
  void Intersect(const Region& region);

  bool Equals(const Region& other) const {
    return skregion_ == other.skregion_;
  }

  gfx::Rect bounds() const {
    return gfx::SkIRectToRect(skregion_.getBounds());
  }

  std::string ToString() const;
  scoped_ptr<base::Value> AsValue() const;

  class CC_EXPORT Iterator {
   public:
    Iterator();
    explicit Iterator(const Region& region);
    ~Iterator();

    gfx::Rect rect() const {
      return gfx::SkIRectToRect(it_.rect());
    }

    void next() {
      it_.next();
    }

    bool has_rect() const {
      return !it_.done();
    }

   private:
    SkRegion::Iterator it_;
  };

 private:
  SkRegion skregion_;
};

inline bool operator==(const Region& a, const Region& b) {
  return a.Equals(b);
}

inline bool operator!=(const Region& a, const Region& b) {
  return !(a == b);
}

inline Region SubtractRegions(const Region& a, const Region& b) {
  Region result = a;
  result.Subtract(b);
  return result;
}

inline Region SubtractRegions(const Region& a, gfx::Rect b) {
  Region result = a;
  result.Subtract(b);
  return result;
}

inline Region IntersectRegions(const Region& a, const Region& b) {
  Region result = a;
  result.Intersect(b);
  return result;
}

inline Region IntersectRegions(const Region& a, gfx::Rect b) {
  Region result = a;
  result.Intersect(b);
  return result;
}

inline Region UnionRegions(const Region& a, const Region& b) {
  Region result = a;
  result.Union(b);
  return result;
}

inline Region UnionRegions(const Region& a, gfx::Rect b) {
  Region result = a;
  result.Union(b);
  return result;
}

}  // namespace cc

#endif  // CC_BASE_REGION_H_