gfx/2d/BasePoint.h@97036ab72558
gfx/2d/BasePoint.h
Tue, 06 Jan 2015 21:39:09 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Tue, 06 Jan 2015 21:39:09 +0100
- branch
- TOR_BUG_9701
- changeset 8
- 97036ab72558
- permissions
- -rw-r--r--
Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.
1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
2 * This Source Code Form is subject to the terms of the Mozilla Public
3 * License, v. 2.0. If a copy of the MPL was not distributed with this
4 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6 #ifndef MOZILLA_GFX_BASEPOINT_H_
7 #define MOZILLA_GFX_BASEPOINT_H_
9 #include <cmath>
10 #include "mozilla/Attributes.h"
12 namespace mozilla {
13 namespace gfx {
15 /**
16 * Do not use this class directly. Subclass it, pass that subclass as the
17 * Sub parameter, and only use that subclass. This allows methods to safely
18 * cast 'this' to 'Sub*'.
19 */
20 template <class T, class Sub>
21 struct BasePoint {
22 T x, y;
24 // Constructors
25 MOZ_CONSTEXPR BasePoint() : x(0), y(0) {}
26 MOZ_CONSTEXPR BasePoint(T aX, T aY) : x(aX), y(aY) {}
28 void MoveTo(T aX, T aY) { x = aX; y = aY; }
29 void MoveBy(T aDx, T aDy) { x += aDx; y += aDy; }
31 // Note that '=' isn't defined so we'll get the
32 // compiler generated default assignment operator
34 bool operator==(const Sub& aPoint) const {
35 return x == aPoint.x && y == aPoint.y;
36 }
37 bool operator!=(const Sub& aPoint) const {
38 return x != aPoint.x || y != aPoint.y;
39 }
41 Sub operator+(const Sub& aPoint) const {
42 return Sub(x + aPoint.x, y + aPoint.y);
43 }
44 Sub operator-(const Sub& aPoint) const {
45 return Sub(x - aPoint.x, y - aPoint.y);
46 }
47 Sub& operator+=(const Sub& aPoint) {
48 x += aPoint.x;
49 y += aPoint.y;
50 return *static_cast<Sub*>(this);
51 }
52 Sub& operator-=(const Sub& aPoint) {
53 x -= aPoint.x;
54 y -= aPoint.y;
55 return *static_cast<Sub*>(this);
56 }
58 Sub operator*(T aScale) const {
59 return Sub(x * aScale, y * aScale);
60 }
61 Sub operator/(T aScale) const {
62 return Sub(x / aScale, y / aScale);
63 }
65 Sub operator-() const {
66 return Sub(-x, -y);
67 }
69 // Round() is *not* rounding to nearest integer if the values are negative.
70 // They are always rounding as floor(n + 0.5).
71 // See https://bugzilla.mozilla.org/show_bug.cgi?id=410748#c14
72 Sub& Round() {
73 x = static_cast<T>(floor(x + 0.5));
74 y = static_cast<T>(floor(y + 0.5));
75 return *static_cast<Sub*>(this);
76 }
78 };
80 }
81 }
83 #endif /* MOZILLA_GFX_BASEPOINT_H_ */
