pjs/gfx/public/nsRegion.h

271 строка
8.9 KiB
C++

/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is
* Dainis Jonitis, <Dainis_Jonitis@swh-t.lv>.
* Portions created by the Initial Developer are Copyright (C) 2001
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#ifndef nsRegion_h__
#define nsRegion_h__
// Implementation of region.
// Region is represented as circular double-linked list of nsRegion::RgnRect structures.
// Rectangles in this list do not overlap and are sorted by (y, x) coordinates.
#include "nsRect.h"
#include "nsPoint.h"
class NS_GFX nsRegion
{
friend class nsRegionRectIterator;
friend class RgnRectMemoryAllocator;
// Special version of nsRect structure for speed optimizations in nsRegion code.
// Most important functions could be made inline and be sure that passed rectangles
// will always be non-empty.
//
// Do not add any new member variables to this structure!
// Otherwise it will break casts from nsRect to nsRectFast, which expect data parts to be identical.
struct nsRectFast : public nsRect
{
nsRectFast () {} // No need to call parent constructor to set default values
nsRectFast (PRInt32 aX, PRInt32 aY, PRInt32 aWidth, PRInt32 aHeight) : nsRect (aX, aY, aWidth, aHeight) {}
nsRectFast (const nsRect& aRect) : nsRect (aRect) {}
// Override nsRect methods to make them inline. Do not check for emptiness.
inline PRBool Contains (const nsRect& aRect) const;
inline PRBool Intersects (const nsRect& aRect) const;
inline PRBool IntersectRect (const nsRect& aRect1, const nsRect& aRect2);
inline void UnionRect (const nsRect& aRect1, const nsRect& aRect2);
};
struct RgnRect : public nsRectFast
{
RgnRect* prev;
RgnRect* next;
RgnRect () {} // No need to call parent constructor to set default values
RgnRect (PRInt32 aX, PRInt32 aY, PRInt32 aWidth, PRInt32 aHeight) : nsRectFast (aX, aY, aWidth, aHeight) {}
RgnRect (const nsRectFast& aRect) : nsRectFast (aRect) {}
void* operator new (size_t) CPP_THROW_NEW;
void operator delete (void* aRect, size_t);
RgnRect& operator = (const RgnRect& aRect) // Do not overwrite prev/next pointers
{
x = aRect.x;
y = aRect.y;
width = aRect.width;
height = aRect.height;
return *this;
}
};
public:
nsRegion () { Init (); }
nsRegion (const nsRect& aRect) { Init (); Copy (aRect); }
nsRegion (const nsRegion& aRegion) { Init (); Copy (aRegion); }
~nsRegion () { SetToElements (0); }
nsRegion& operator = (const nsRect& aRect) { Copy (aRect); return *this; }
nsRegion& operator = (const nsRegion& aRegion) { Copy (aRegion); return *this; }
nsRegion& And (const nsRegion& aRgn1, const nsRegion& aRgn2);
nsRegion& And (const nsRegion& aRegion, const nsRect& aRect);
nsRegion& And (const nsRect& aRect, const nsRegion& aRegion)
{
return And (aRegion, aRect);
}
nsRegion& And (const nsRect& aRect1, const nsRect& aRect2)
{
nsRect TmpRect;
TmpRect.IntersectRect (aRect1, aRect2);
return Copy (TmpRect);
}
nsRegion& Or (const nsRegion& aRgn1, const nsRegion& aRgn2);
nsRegion& Or (const nsRegion& aRegion, const nsRect& aRect);
nsRegion& Or (const nsRect& aRect, const nsRegion& aRegion)
{
return Or (aRegion, aRect);
}
nsRegion& Or (const nsRect& aRect1, const nsRect& aRect2)
{
Copy (aRect1);
return Or (*this, aRect2);
}
nsRegion& Xor (const nsRegion& aRgn1, const nsRegion& aRgn2);
nsRegion& Xor (const nsRegion& aRegion, const nsRect& aRect);
nsRegion& Xor (const nsRect& aRect, const nsRegion& aRegion)
{
return Xor (aRegion, aRect);
}
nsRegion& Xor (const nsRect& aRect1, const nsRect& aRect2)
{
Copy (aRect1);
return Xor (*this, aRect2);
}
nsRegion& Sub (const nsRegion& aRgn1, const nsRegion& aRgn2);
nsRegion& Sub (const nsRegion& aRegion, const nsRect& aRect);
nsRegion& Sub (const nsRect& aRect, const nsRegion& aRegion)
{
return Sub (nsRegion (aRect), aRegion);
}
nsRegion& Sub (const nsRect& aRect1, const nsRect& aRect2)
{
Copy (aRect1);
return Sub (*this, aRect2);
}
PRBool Contains (const nsRect& aRect) const;
PRBool Intersects (const nsRect& aRect) const;
void MoveBy (PRInt32 aXOffset, PRInt32 aYOffset)
{
MoveBy (nsPoint (aXOffset, aYOffset));
}
void MoveBy (nsPoint aPt);
void SetEmpty ()
{
SetToElements (0);
mBoundRect.SetRect (0, 0, 0, 0);
}
PRBool IsEmpty () const { return mRectCount == 0; }
PRBool IsComplex () const { return mRectCount > 1; }
PRBool IsEqual (const nsRegion& aRegion) const;
PRUint32 GetNumRects () const { return mRectCount; }
const nsRect& GetBounds () const { return mBoundRect; }
/**
* Make sure the region has at most aMaxRects by adding area to it
* if necessary. The simplified region will be a superset of the
* original region. The simplified region's bounding box will be
* the same as for the current region.
*/
void SimplifyOutward (PRUint32 aMaxRects);
/**
* Make sure the region has at most aMaxRects by removing area from
* it if necessary. The simplified region will be a subset of the
* original region.
*/
void SimplifyInward (PRUint32 aMaxRects);
/**
* Efficiently try to remove a rectangle from this region. The actual
* area removed could be some sub-area contained by the rectangle
* (even possibly nothing at all).
*
* We remove all rectangles that are contained by aRect.
*/
void SimpleSubtract (const nsRect& aRect);
/**
* Efficiently try to remove a region from this region. The actual
* area removed could be some sub-area contained by aRegion
* (even possibly nothing at all).
*
* We remove all rectangles of this region that are contained by
* a rectangle of aRegion.
*/
void SimpleSubtract (const nsRegion& aRegion);
private:
PRUint32 mRectCount;
RgnRect* mCurRect;
RgnRect mRectListHead;
nsRectFast mBoundRect;
void Init ();
nsRegion& Copy (const nsRegion& aRegion);
nsRegion& Copy (const nsRect& aRect);
void InsertBefore (RgnRect* aNewRect, RgnRect* aRelativeRect);
void InsertAfter (RgnRect* aNewRect, RgnRect* aRelativeRect);
void SetToElements (PRUint32 aCount);
RgnRect* Remove (RgnRect* aRect);
void InsertInPlace (RgnRect* aRect, PRBool aOptimizeOnFly = PR_FALSE);
inline void SaveLinkChain ();
inline void RestoreLinkChain ();
void Optimize ();
void SubRegion (const nsRegion& aRegion, nsRegion& aResult) const;
void SubRect (const nsRectFast& aRect, nsRegion& aResult, nsRegion& aCompleted) const;
void SubRect (const nsRectFast& aRect, nsRegion& aResult) const
{ SubRect (aRect, aResult, aResult); }
void Merge (const nsRegion& aRgn1, const nsRegion& aRgn2);
void MoveInto (nsRegion& aDestRegion, const RgnRect* aStartRect);
void MoveInto (nsRegion& aDestRegion)
{ MoveInto (aDestRegion, mRectListHead.next); }
};
// Allow read-only access to region rectangles by iterating the list
class NS_GFX nsRegionRectIterator
{
const nsRegion* mRegion;
const nsRegion::RgnRect* mCurPtr;
public:
nsRegionRectIterator (const nsRegion& aRegion)
{
mRegion = &aRegion;
mCurPtr = &aRegion.mRectListHead;
}
const nsRect* Next ()
{
mCurPtr = mCurPtr->next;
return (mCurPtr != &mRegion->mRectListHead) ? mCurPtr : nsnull;
}
const nsRect* Prev ()
{
mCurPtr = mCurPtr->prev;
return (mCurPtr != &mRegion->mRectListHead) ? mCurPtr : nsnull;
}
void Reset ()
{
mCurPtr = &mRegion->mRectListHead;
}
};
#endif