gecko-dev/gfx/2d/RectAbsolute.h

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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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_ABSOLUTE_H_
#define MOZILLA_GFX_RECT_ABSOLUTE_H_
#include <algorithm>
#include <cstdint>
#include "mozilla/Attributes.h"
#include "Point.h"
#include "Rect.h"
#include "Types.h"
namespace mozilla {
template <typename>
struct IsPixel;
namespace gfx {
/**
* A RectAbsolute is similar to a Rect (see BaseRect.h), but represented as
* (x1, y1, x2, y2) instead of (x, y, width, height).
*
* Unless otherwise indicated, methods on this class correspond
* to methods on BaseRect.
*
* The API is currently very bare-bones; it may be extended as needed.
*
* Do not use this class directly. Subclass it, pass that subclass as the
* Sub parameter, and only use that subclass.
*/
template <class T, class Sub, class Point, class Rect>
struct BaseRectAbsolute {
protected:
T left, top, right, bottom;
public:
BaseRectAbsolute() : left(0), top(0), right(0), bottom(0) {}
BaseRectAbsolute(T aLeft, T aTop, T aRight, T aBottom)
: left(aLeft), top(aTop), right(aRight), bottom(aBottom) {}
MOZ_ALWAYS_INLINE T X() const { return left; }
MOZ_ALWAYS_INLINE T Y() const { return top; }
MOZ_ALWAYS_INLINE T Width() const { return right - left; }
MOZ_ALWAYS_INLINE T Height() const { return bottom - top; }
MOZ_ALWAYS_INLINE T XMost() const { return right; }
MOZ_ALWAYS_INLINE T YMost() const { return bottom; }
MOZ_ALWAYS_INLINE const T& Left() const { return left; }
MOZ_ALWAYS_INLINE const T& Right() const { return right; }
MOZ_ALWAYS_INLINE const T& Top() const { return top; }
MOZ_ALWAYS_INLINE const T& Bottom() const { return bottom; }
MOZ_ALWAYS_INLINE T& Left() { return left; }
MOZ_ALWAYS_INLINE T& Right() { return right; }
MOZ_ALWAYS_INLINE T& Top() { return top; }
MOZ_ALWAYS_INLINE T& Bottom() { return bottom; }
T Area() const { return Width() * Height(); }
void Inflate(T aD) { Inflate(aD, aD); }
void Inflate(T aDx, T aDy) {
left -= aDx;
top -= aDy;
right += aDx;
bottom += aDy;
}
MOZ_ALWAYS_INLINE void SetBox(T aLeft, T aTop, T aRight, T aBottom) {
left = aLeft;
top = aTop;
right = aRight;
bottom = aBottom;
}
void SetLeftEdge(T aLeft) { left = aLeft; }
void SetRightEdge(T aRight) { right = aRight; }
void SetTopEdge(T aTop) { top = aTop; }
void SetBottomEdge(T aBottom) { bottom = aBottom; }
static Sub FromRect(const Rect& aRect) {
if (aRect.Overflows()) {
return Sub();
}
return Sub(aRect.x, aRect.y, aRect.XMost(), aRect.YMost());
}
MOZ_MUST_USE Sub Intersect(const Sub& aOther) const {
Sub result;
result.left = std::max<T>(left, aOther.left);
result.top = std::max<T>(top, aOther.top);
result.right = std::min<T>(right, aOther.right);
result.bottom = std::min<T>(bottom, aOther.bottom);
if (result.right < result.left || result.bottom < result.top) {
result.SizeTo(0, 0);
}
return result;
}
bool IsEmpty() const { return right <= left || bottom <= top; }
bool IsEqualEdges(const Sub& aOther) const {
return left == aOther.left && top == aOther.top && right == aOther.right &&
bottom == aOther.bottom;
}
bool IsEqualInterior(const Sub& aRect) const {
return IsEqualEdges(aRect) || (IsEmpty() && aRect.IsEmpty());
}
MOZ_ALWAYS_INLINE void MoveBy(T aDx, T aDy) {
left += aDx;
right += aDx;
top += aDy;
bottom += aDy;
}
MOZ_ALWAYS_INLINE void MoveBy(const Point& aPoint) {
left += aPoint.x;
right += aPoint.x;
top += aPoint.y;
bottom += aPoint.y;
}
MOZ_ALWAYS_INLINE void SizeTo(T aWidth, T aHeight) {
right = left + aWidth;
bottom = top + aHeight;
}
bool Contains(const Sub& aRect) const {
return aRect.IsEmpty() || (left <= aRect.left && aRect.right <= right &&
top <= aRect.top && aRect.bottom <= bottom);
}
bool Contains(T aX, T aY) const {
return (left <= aX && aX < right && top <= aY && aY < bottom);
}
bool Intersects(const Sub& aRect) const {
return !IsEmpty() && !aRect.IsEmpty() && left < aRect.right &&
aRect.left < right && top < aRect.bottom && aRect.top < bottom;
}
void SetEmpty() { left = right = top = bottom = 0; }
// Returns the smallest rectangle that contains both the area of both
// this and aRect2.
// Thus, empty input rectangles are ignored.
// If both rectangles are empty, returns this.
// WARNING! This is not safe against overflow, prefer using SafeUnion instead
// when dealing with int-based rects.
MOZ_MUST_USE Sub Union(const Sub& aRect) const {
if (IsEmpty()) {
return aRect;
} else if (aRect.IsEmpty()) {
return *static_cast<const Sub*>(this);
} else {
return UnionEdges(aRect);
}
}
// Returns the smallest rectangle that contains both the points (including
// edges) of both aRect1 and aRect2.
// Thus, empty input rectangles are allowed to affect the result.
// WARNING! This is not safe against overflow, prefer using SafeUnionEdges
// instead when dealing with int-based rects.
MOZ_MUST_USE Sub UnionEdges(const Sub& aRect) const {
Sub result;
result.left = std::min(left, aRect.left);
result.top = std::min(top, aRect.top);
result.right = std::max(XMost(), aRect.XMost());
result.bottom = std::max(YMost(), aRect.YMost());
return result;
}
// Scale 'this' by aScale without doing any rounding.
void Scale(T aScale) { Scale(aScale, aScale); }
// Scale 'this' by aXScale and aYScale, without doing any rounding.
void Scale(T aXScale, T aYScale) {
right = XMost() * aXScale;
bottom = YMost() * aYScale;
left = left * aXScale;
top = top * aYScale;
}
// Scale 'this' by aScale, converting coordinates to integers so that the
// result is the smallest integer-coordinate rectangle containing the
// unrounded result. Note: this can turn an empty rectangle into a non-empty
// rectangle
void ScaleRoundOut(double aScale) { ScaleRoundOut(aScale, aScale); }
// Scale 'this' by aXScale and aYScale, converting coordinates to integers so
// that the result is the smallest integer-coordinate rectangle containing the
// unrounded result.
// Note: this can turn an empty rectangle into a non-empty rectangle
void ScaleRoundOut(double aXScale, double aYScale) {
right = static_cast<T>(ceil(double(XMost()) * aXScale));
bottom = static_cast<T>(ceil(double(YMost()) * aYScale));
left = static_cast<T>(floor(double(left) * aXScale));
top = static_cast<T>(floor(double(top) * aYScale));
}
// Scale 'this' by aScale, converting coordinates to integers so that the
// result is the largest integer-coordinate rectangle contained by the
// unrounded result.
void ScaleRoundIn(double aScale) { ScaleRoundIn(aScale, aScale); }
// Scale 'this' by aXScale and aYScale, converting coordinates to integers so
// that the result is the largest integer-coordinate rectangle contained by
// the unrounded result.
void ScaleRoundIn(double aXScale, double aYScale) {
right = static_cast<T>(floor(double(XMost()) * aXScale));
bottom = static_cast<T>(floor(double(YMost()) * aYScale));
left = static_cast<T>(ceil(double(left) * aXScale));
top = static_cast<T>(ceil(double(top) * aYScale));
}
// Scale 'this' by 1/aScale, converting coordinates to integers so that the
// result is the smallest integer-coordinate rectangle containing the
// unrounded result. Note: this can turn an empty rectangle into a non-empty
// rectangle
void ScaleInverseRoundOut(double aScale) {
ScaleInverseRoundOut(aScale, aScale);
}
// Scale 'this' by 1/aXScale and 1/aYScale, converting coordinates to integers
// so that the result is the smallest integer-coordinate rectangle containing
// the unrounded result. Note: this can turn an empty rectangle into a
// non-empty rectangle
void ScaleInverseRoundOut(double aXScale, double aYScale) {
right = static_cast<T>(ceil(double(XMost()) / aXScale));
bottom = static_cast<T>(ceil(double(YMost()) / aYScale));
left = static_cast<T>(floor(double(left) / aXScale));
top = static_cast<T>(floor(double(top) / aYScale));
}
// Scale 'this' by 1/aScale, converting coordinates to integers so that the
// result is the largest integer-coordinate rectangle contained by the
// unrounded result.
void ScaleInverseRoundIn(double aScale) {
ScaleInverseRoundIn(aScale, aScale);
}
// Scale 'this' by 1/aXScale and 1/aYScale, converting coordinates to integers
// so that the result is the largest integer-coordinate rectangle contained by
// the unrounded result.
void ScaleInverseRoundIn(double aXScale, double aYScale) {
right = static_cast<T>(floor(double(XMost()) / aXScale));
bottom = static_cast<T>(floor(double(YMost()) / aYScale));
left = static_cast<T>(ceil(double(left) / aXScale));
top = static_cast<T>(ceil(double(top) / aYScale));
}
/**
* Translate this rectangle to be inside aRect. If it doesn't fit inside
* aRect then the dimensions that don't fit will be shrunk so that they
* do fit. The resulting rect is returned.
*/
MOZ_MUST_USE Sub MoveInsideAndClamp(const Sub& aRect) const {
T newLeft = std::max(aRect.left, left);
T newTop = std::max(aRect.top, top);
T width = std::min(aRect.Width(), Width());
T height = std::min(aRect.Height(), Height());
Sub rect(newLeft, newTop, newLeft + width, newTop + height);
newLeft = std::min(rect.right, aRect.right) - width;
newTop = std::min(rect.bottom, aRect.bottom) - height;
rect.MoveBy(newLeft - rect.left, newTop - rect.top);
return rect;
}
friend std::ostream& operator<<(
std::ostream& stream,
const BaseRectAbsolute<T, Sub, Point, Rect>& aRect) {
return stream << '(' << aRect.left << ',' << aRect.top << ',' << aRect.right
<< ',' << aRect.bottom << ')';
}
};
template <class Units>
struct IntRectAbsoluteTyped
: public BaseRectAbsolute<int32_t, IntRectAbsoluteTyped<Units>,
IntPointTyped<Units>, IntRectTyped<Units>>,
public Units {
static_assert(IsPixel<Units>::value,
"'units' must be a coordinate system tag");
typedef BaseRectAbsolute<int32_t, IntRectAbsoluteTyped<Units>,
IntPointTyped<Units>, IntRectTyped<Units>>
Super;
typedef IntParam<int32_t> ToInt;
IntRectAbsoluteTyped() : Super() {}
IntRectAbsoluteTyped(ToInt aLeft, ToInt aTop, ToInt aRight, ToInt aBottom)
: Super(aLeft.value, aTop.value, aRight.value, aBottom.value) {}
};
template <class Units>
struct RectAbsoluteTyped
: public BaseRectAbsolute<Float, RectAbsoluteTyped<Units>,
PointTyped<Units>, RectTyped<Units>>,
public Units {
static_assert(IsPixel<Units>::value,
"'units' must be a coordinate system tag");
typedef BaseRectAbsolute<Float, RectAbsoluteTyped<Units>, PointTyped<Units>,
RectTyped<Units>>
Super;
RectAbsoluteTyped() : Super() {}
RectAbsoluteTyped(Float aLeft, Float aTop, Float aRight, Float aBottom)
: Super(aLeft, aTop, aRight, aBottom) {}
};
typedef IntRectAbsoluteTyped<UnknownUnits> IntRectAbsolute;
} // namespace gfx
} // namespace mozilla
#endif /* MOZILLA_GFX_RECT_ABSOLUTE_H_ */