gecko-dev/gfx/2d/Rect.h
Markus Stange 6b192b5a0c Bug 1298206 - Make IntersectMaybeRects usable for Maybe<nsRect>. r=botond
MozReview-Commit-ID: 4OJQj206gI2

--HG--
extra : rebase_source : ce6d47968a655dd820cb7fecc26aa9394668b3f9
2016-08-24 17:40:58 -04:00

302 lines
10 KiB
C++

/* -*- Mode: c++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef MOZILLA_GFX_RECT_H_
#define MOZILLA_GFX_RECT_H_
#include "BaseRect.h"
#include "BaseMargin.h"
#include "NumericTools.h"
#include "Point.h"
#include "Tools.h"
#include "mozilla/Maybe.h"
#include <cmath>
namespace mozilla {
template <typename> struct IsPixel;
namespace gfx {
template<class units>
struct IntMarginTyped:
public BaseMargin<int32_t, IntMarginTyped<units> >,
public units {
static_assert(IsPixel<units>::value,
"'units' must be a coordinate system tag");
typedef BaseMargin<int32_t, IntMarginTyped<units> > Super;
IntMarginTyped() : Super() {}
IntMarginTyped(int32_t aTop, int32_t aRight, int32_t aBottom, int32_t aLeft) :
Super(aTop, aRight, aBottom, aLeft) {}
// XXX When all of the code is ported, the following functions to convert
// to and from unknown types should be removed.
static IntMarginTyped<units> FromUnknownMargin(const IntMarginTyped<UnknownUnits>& aMargin) {
return IntMarginTyped<units>(aMargin.top, aMargin.right,
aMargin.bottom, aMargin.left);
}
IntMarginTyped<UnknownUnits> ToUnknownMargin() const {
return IntMarginTyped<UnknownUnits>(this->top, this->right,
this->bottom, this->left);
}
};
typedef IntMarginTyped<UnknownUnits> IntMargin;
template<class units, class F = Float>
struct MarginTyped:
public BaseMargin<F, MarginTyped<units> >,
public units {
static_assert(IsPixel<units>::value,
"'units' must be a coordinate system tag");
typedef BaseMargin<F, MarginTyped<units, F> > Super;
MarginTyped() : Super() {}
MarginTyped(F aTop, F aRight, F aBottom, F aLeft) :
Super(aTop, aRight, aBottom, aLeft) {}
explicit MarginTyped(const IntMarginTyped<units>& aMargin) :
Super(F(aMargin.top), F(aMargin.right),
F(aMargin.bottom), F(aMargin.left)) {}
};
typedef MarginTyped<UnknownUnits> Margin;
typedef MarginTyped<UnknownUnits, double> MarginDouble;
template<class units>
IntMarginTyped<units> RoundedToInt(const MarginTyped<units>& aMargin)
{
return IntMarginTyped<units>(int32_t(floorf(aMargin.top + 0.5f)),
int32_t(floorf(aMargin.right + 0.5f)),
int32_t(floorf(aMargin.bottom + 0.5f)),
int32_t(floorf(aMargin.left + 0.5f)));
}
template<class units>
struct IntRectTyped :
public BaseRect<int32_t, IntRectTyped<units>, IntPointTyped<units>, IntSizeTyped<units>, IntMarginTyped<units> >,
public units {
static_assert(IsPixel<units>::value,
"'units' must be a coordinate system tag");
typedef BaseRect<int32_t, IntRectTyped<units>, IntPointTyped<units>, IntSizeTyped<units>, IntMarginTyped<units> > Super;
typedef IntRectTyped<units> Self;
IntRectTyped() : Super() {}
IntRectTyped(const IntPointTyped<units>& aPos, const IntSizeTyped<units>& aSize) :
Super(aPos, aSize) {}
IntRectTyped(int32_t _x, int32_t _y, int32_t _width, int32_t _height) :
Super(_x, _y, _width, _height) {}
// Rounding isn't meaningful on an integer rectangle.
void Round() {}
void RoundIn() {}
void RoundOut() {}
// XXX When all of the code is ported, the following functions to convert
// to and from unknown types should be removed.
static IntRectTyped<units> FromUnknownRect(const IntRectTyped<UnknownUnits>& rect) {
return IntRectTyped<units>(rect.x, rect.y, rect.width, rect.height);
}
IntRectTyped<UnknownUnits> ToUnknownRect() const {
return IntRectTyped<UnknownUnits>(this->x, this->y, this->width, this->height);
}
bool Overflows() const {
CheckedInt<int32_t> xMost = this->x;
xMost += this->width;
CheckedInt<int32_t> yMost = this->y;
yMost += this->height;
return !xMost.isValid() || !yMost.isValid();
}
// Same as Union(), but in the cases where aRect is non-empty, the union is
// done while guarding against overflow. If an overflow is detected, Nothing
// is returned.
MOZ_MUST_USE Maybe<Self> SafeUnion(const Self& aRect) const
{
if (this->IsEmpty()) {
return aRect.Overflows() ? Nothing() : Some(aRect);
} else if (aRect.IsEmpty()) {
return Some(*static_cast<const Self*>(this));
} else {
return this->SafeUnionEdges(aRect);
}
}
// Same as UnionEdges, but guards against overflow. If an overflow is detected,
// Nothing is returned.
MOZ_MUST_USE Maybe<Self> SafeUnionEdges(const Self& aRect) const
{
if (this->Overflows() || aRect.Overflows()) {
return Nothing();
}
// If neither |this| nor |aRect| overflow, then their XMost/YMost values
// should be safe to use.
CheckedInt<int32_t> newX = std::min(this->x, aRect.x);
CheckedInt<int32_t> newY = std::min(this->y, aRect.y);
CheckedInt<int32_t> newXMost = std::max(this->XMost(), aRect.XMost());
CheckedInt<int32_t> newYMost = std::max(this->YMost(), aRect.YMost());
CheckedInt<int32_t> newW = newXMost - newX;
CheckedInt<int32_t> newH = newYMost - newY;
if (!newW.isValid() || !newH.isValid()) {
return Nothing();
}
return Some(Self(newX.value(), newY.value(), newW.value(), newH.value()));
}
// This is here only to keep IPDL-generated code happy. DO NOT USE.
bool operator==(const IntRectTyped<units>& aRect) const
{
return IntRectTyped<units>::IsEqualEdges(aRect);
}
void InflateToMultiple(const IntSizeTyped<units>& aTileSize)
{
if (this->IsEmpty()) {
return;
}
int32_t yMost = this->YMost();
int32_t xMost = this->XMost();
this->x = mozilla::RoundDownToMultiple(this->x, aTileSize.width);
this->y = mozilla::RoundDownToMultiple(this->y, aTileSize.height);
xMost = mozilla::RoundUpToMultiple(xMost, aTileSize.width);
yMost = mozilla::RoundUpToMultiple(yMost, aTileSize.height);
this->width = xMost - this->x;
this->height = yMost - this->y;
}
};
typedef IntRectTyped<UnknownUnits> IntRect;
template<class units, class F = Float>
struct RectTyped :
public BaseRect<F, RectTyped<units, F>, PointTyped<units, F>, SizeTyped<units, F>, MarginTyped<units, F> >,
public units {
static_assert(IsPixel<units>::value,
"'units' must be a coordinate system tag");
typedef BaseRect<F, RectTyped<units, F>, PointTyped<units, F>, SizeTyped<units, F>, MarginTyped<units, F> > Super;
RectTyped() : Super() {}
RectTyped(const PointTyped<units, F>& aPos, const SizeTyped<units, F>& aSize) :
Super(aPos, aSize) {}
RectTyped(F _x, F _y, F _width, F _height) :
Super(_x, _y, _width, _height) {}
explicit RectTyped(const IntRectTyped<units>& rect) :
Super(F(rect.x), F(rect.y),
F(rect.width), F(rect.height)) {}
void NudgeToIntegers()
{
NudgeToInteger(&(this->x));
NudgeToInteger(&(this->y));
NudgeToInteger(&(this->width));
NudgeToInteger(&(this->height));
}
bool ToIntRect(IntRectTyped<units> *aOut) const
{
*aOut = IntRectTyped<units>(int32_t(this->X()), int32_t(this->Y()),
int32_t(this->Width()), int32_t(this->Height()));
return RectTyped<units, F>(F(aOut->x), F(aOut->y),
F(aOut->width), F(aOut->height))
.IsEqualEdges(*this);
}
// XXX When all of the code is ported, the following functions to convert to and from
// unknown types should be removed.
static RectTyped<units, F> FromUnknownRect(const RectTyped<UnknownUnits, F>& rect) {
return RectTyped<units, F>(rect.x, rect.y, rect.width, rect.height);
}
RectTyped<UnknownUnits, F> ToUnknownRect() const {
return RectTyped<UnknownUnits, F>(this->x, this->y, this->width, this->height);
}
// This is here only to keep IPDL-generated code happy. DO NOT USE.
bool operator==(const RectTyped<units, F>& aRect) const
{
return RectTyped<units, F>::IsEqualEdges(aRect);
}
};
typedef RectTyped<UnknownUnits> Rect;
typedef RectTyped<UnknownUnits, double> RectDouble;
template<class units>
IntRectTyped<units> RoundedToInt(const RectTyped<units>& aRect)
{
RectTyped<units> copy(aRect);
copy.Round();
return IntRectTyped<units>(int32_t(copy.x),
int32_t(copy.y),
int32_t(copy.width),
int32_t(copy.height));
}
template<class units>
IntRectTyped<units> RoundedIn(const RectTyped<units>& aRect)
{
RectTyped<units> copy(aRect);
copy.RoundIn();
return IntRectTyped<units>(int32_t(copy.x),
int32_t(copy.y),
int32_t(copy.width),
int32_t(copy.height));
}
template<class units>
IntRectTyped<units> RoundedOut(const RectTyped<units>& aRect)
{
RectTyped<units> copy(aRect);
copy.RoundOut();
return IntRectTyped<units>(int32_t(copy.x),
int32_t(copy.y),
int32_t(copy.width),
int32_t(copy.height));
}
template<class units>
IntRectTyped<units> TruncatedToInt(const RectTyped<units>& aRect) {
return IntRectTyped<units>(int32_t(aRect.x),
int32_t(aRect.y),
int32_t(aRect.width),
int32_t(aRect.height));
}
template<class units>
RectTyped<units> IntRectToRect(const IntRectTyped<units>& aRect)
{
return RectTyped<units>(aRect.x, aRect.y, aRect.width, aRect.height);
}
// Convenience function for intersecting two rectangles wrapped in Maybes.
template <typename T>
Maybe<T>
IntersectMaybeRects(const Maybe<T>& a, const Maybe<T>& b)
{
if (!a) {
return b;
} else if (!b) {
return a;
} else {
return Some(a->Intersect(*b));
}
}
} // namespace gfx
} // namespace mozilla
#endif /* MOZILLA_GFX_RECT_H_ */