ppapi/cpp/rect.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "ppapi/cpp/rect.h"
   6
   7 #include <algorithm>
   8
   9 namespace {
  10
  11 void AdjustAlongAxis(int32_t dst_origin, int32_t dst_size,
  12                      int32_t* origin, int32_t* size) {
  13   if (*origin < dst_origin) {
  14     *origin = dst_origin;
  15     *size = std::min(dst_size, *size);
  16   } else {
  17     *size = std::min(dst_size, *size);
  18     *origin = std::min(dst_origin + dst_size, *origin + *size) - *size;
  19   }
  20 }
  21
  22 }  // namespace
  23
  24 namespace pp {
  25
  26 void Rect::Inset(int32_t left, int32_t top, int32_t right, int32_t bottom) {
  27   Offset(left, top);
  28   set_width(std::max<int32_t>(width() - left - right, 0));
  29   set_height(std::max<int32_t>(height() - top - bottom, 0));
  30 }
  31
  32 void Rect::Offset(int32_t horizontal, int32_t vertical) {
  33   rect_.point.x += horizontal;
  34   rect_.point.y += vertical;
  35 }
  36
  37 bool Rect::Contains(int32_t point_x, int32_t point_y) const {
  38   return (point_x >= x()) && (point_x < right()) &&
  39          (point_y >= y()) && (point_y < bottom());
  40 }
  41
  42 bool Rect::Contains(const Rect& rect) const {
  43   return (rect.x() >= x() && rect.right() <= right() &&
  44           rect.y() >= y() && rect.bottom() <= bottom());
  45 }
  46
  47 bool Rect::Intersects(const Rect& rect) const {
  48   return !(rect.x() >= right() || rect.right() <= x() ||
  49            rect.y() >= bottom() || rect.bottom() <= y());
  50 }
  51
  52 Rect Rect::Intersect(const Rect& rect) const {
  53   int32_t rx = std::max(x(), rect.x());
  54   int32_t ry = std::max(y(), rect.y());
  55   int32_t rr = std::min(right(), rect.right());
  56   int32_t rb = std::min(bottom(), rect.bottom());
  57
  58   if (rx >= rr || ry >= rb)
  59     rx = ry = rr = rb = 0;  // non-intersecting
  60
  61   return Rect(rx, ry, rr - rx, rb - ry);
  62 }
  63
  64 Rect Rect::Union(const Rect& rect) const {
  65   // special case empty rects...
  66   if (IsEmpty())
  67     return rect;
  68   if (rect.IsEmpty())
  69     return *this;
  70
  71   int32_t rx = std::min(x(), rect.x());
  72   int32_t ry = std::min(y(), rect.y());
  73   int32_t rr = std::max(right(), rect.right());
  74   int32_t rb = std::max(bottom(), rect.bottom());
  75
  76   return Rect(rx, ry, rr - rx, rb - ry);
  77 }
  78
  79 Rect Rect::Subtract(const Rect& rect) const {
  80   // boundary cases:
  81   if (!Intersects(rect))
  82     return *this;
  83   if (rect.Contains(*this))
  84     return Rect();
  85
  86   int32_t rx = x();
  87   int32_t ry = y();
  88   int32_t rr = right();
  89   int32_t rb = bottom();
  90
  91   if (rect.y() <= y() && rect.bottom() >= bottom()) {
  92     // complete intersection in the y-direction
  93     if (rect.x() <= x()) {
  94       rx = rect.right();
  95     } else {
  96       rr = rect.x();
  97     }
  98   } else if (rect.x() <= x() && rect.right() >= right()) {
  99     // complete intersection in the x-direction
 100     if (rect.y() <= y()) {
 101       ry = rect.bottom();
 102     } else {
 103       rb = rect.y();
 104     }
 105   }
 106   return Rect(rx, ry, rr - rx, rb - ry);
 107 }
 108
 109 Rect Rect::AdjustToFit(const Rect& rect) const {
 110   int32_t new_x = x();
 111   int32_t new_y = y();
 112   int32_t new_width = width();
 113   int32_t new_height = height();
 114   AdjustAlongAxis(rect.x(), rect.width(), &new_x, &new_width);
 115   AdjustAlongAxis(rect.y(), rect.height(), &new_y, &new_height);
 116   return Rect(new_x, new_y, new_width, new_height);
 117 }
 118
 119 Point Rect::CenterPoint() const {
 120   return Point(x() + (width() + 1) / 2, y() + (height() + 1) / 2);
 121 }
 122
 123 bool Rect::SharesEdgeWith(const Rect& rect) const {
 124   return (y() == rect.y() && height() == rect.height() &&
 125              (x() == rect.right() || right() == rect.x())) ||
 126          (x() == rect.x() && width() == rect.width() &&
 127              (y() == rect.bottom() || bottom() == rect.y()));
 128 }
 129
 130 }  // namespace pp