skia2/include/core/SkClipStack.h
2012-07-16 18:52:29 +00:00

136 lines
3.4 KiB
C++

/*
* Copyright 2011 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SkClipStack_DEFINED
#define SkClipStack_DEFINED
#include "SkDeque.h"
#include "SkRegion.h"
struct SkRect;
class SkPath;
class SK_API SkClipStack {
public:
SkClipStack();
SkClipStack(const SkClipStack& b);
~SkClipStack();
SkClipStack& operator=(const SkClipStack& b);
bool operator==(const SkClipStack& b) const;
bool operator!=(const SkClipStack& b) const { return !(*this == b); }
void reset();
int getSaveCount() const { return fSaveCount; }
void save();
void restore();
void clipDevRect(const SkIRect& ir, SkRegion::Op op) {
SkRect r;
r.set(ir);
this->clipDevRect(r, op, false);
}
void clipDevRect(const SkRect&, SkRegion::Op, bool doAA);
void clipDevPath(const SkPath&, SkRegion::Op, bool doAA);
private:
struct Rec;
public:
class Iter {
public:
enum IterStart {
kFront_IterStart = SkDeque::Iter::kFront_IterStart,
kBack_IterStart = SkDeque::Iter::kBack_IterStart
};
/**
* Creates an uninitialized iterator. Must be reset()
*/
Iter();
Iter(const SkClipStack& stack, IterStart startLoc);
struct Clip {
Clip() : fRect(NULL), fPath(NULL), fOp(SkRegion::kIntersect_Op),
fDoAA(false) {}
friend bool operator==(const Clip& a, const Clip& b);
friend bool operator!=(const Clip& a, const Clip& b);
const SkRect* fRect; // if non-null, this is a rect clip
const SkPath* fPath; // if non-null, this is a path clip
SkRegion::Op fOp;
bool fDoAA;
};
/**
* Return the clip for this element in the iterator. If next() returns
* NULL, then the iterator is done. The type of clip is determined by
* the pointers fRect and fPath:
*
* fRect==NULL fPath!=NULL path clip
* fRect!=NULL fPath==NULL rect clip
* fRect==NULL fPath==NULL empty clip
*/
const Clip* next();
const Clip* prev();
/**
* Restarts the iterator on a clip stack.
*/
void reset(const SkClipStack& stack, IterStart startLoc);
private:
Clip fClip;
SkDeque::Iter fIter;
/**
* updateClip updates fClip to the current state of fIter. It unifies
* functionality needed by both next() and prev().
*/
const Clip* updateClip(const SkClipStack::Rec* rec);
};
// Inherit privately from Iter to prevent access to reverse iteration
class B2FIter : private Iter {
public:
B2FIter() {}
/**
* Wrap Iter's 2 parameter ctor to force initialization to the
* beginning of the deque
*/
B2FIter(const SkClipStack& stack)
: INHERITED(stack, kFront_IterStart) {
}
using Iter::Clip;
using Iter::next;
/**
* Wrap Iter::reset to force initialization to the
* beginning of the deque
*/
void reset(const SkClipStack& stack) {
this->INHERITED::reset(stack, kFront_IterStart);
}
private:
typedef Iter INHERITED;
};
private:
friend class Iter;
SkDeque fDeque;
int fSaveCount;
};
#endif