chrome/browser/chromeos/ui/accessibility_focus_ring.cc

   1 // Copyright 2014 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 "chrome/browser/chromeos/ui/accessibility_focus_ring.h"
   6
   7 #include "base/logging.h"
   8
   9 namespace chromeos {
  10
  11 // static
  12 AccessibilityFocusRing AccessibilityFocusRing::CreateWithRect(
  13     const gfx::Rect& bounds, int margin) {
  14   // Compute the height of the top and bottom cap.
  15   int cap_height = std::min(bounds.height() / 2, margin * 2);
  16
  17   gfx::Rect top(bounds.x(), bounds.y(),
  18                 bounds.width(), cap_height);
  19   gfx::Rect bottom(bounds.x(), bounds.bottom() - cap_height,
  20                    bounds.width(), cap_height);
  21   gfx::Rect body(bounds.x(), top.bottom(),
  22                  bounds.width(), bottom.y() - top.bottom());
  23
  24   return CreateWithParagraphShape(top, body, bottom, margin);
  25 }
  26
  27 // static
  28 AccessibilityFocusRing AccessibilityFocusRing::Interpolate(
  29     const AccessibilityFocusRing& r1,
  30     const AccessibilityFocusRing& r2,
  31     double fraction) {
  32   AccessibilityFocusRing dst;
  33   for (int i = 0; i < 36; ++i) {
  34     dst.points[i] = gfx::Point(
  35         r1.points[i].x() * (1 - fraction) + r2.points[i].x() * fraction,
  36         r1.points[i].y() * (1 - fraction) + r2.points[i].y() * fraction);
  37   }
  38   return dst;
  39 }
  40
  41 // static
  42 AccessibilityFocusRing AccessibilityFocusRing::CreateWithParagraphShape(
  43     const gfx::Rect& orig_top_line,
  44     const gfx::Rect& orig_body,
  45     const gfx::Rect& orig_bottom_line,
  46     int margin) {
  47   gfx::Rect top = orig_top_line;
  48   gfx::Rect middle = orig_body;
  49   gfx::Rect bottom = orig_bottom_line;
  50
  51   int min_height = std::min(top.height(), bottom.height());
  52   margin = std::min(margin, min_height / 2);
  53
  54   if (top.x() <= middle.x() + 2 * margin) {
  55     top.set_width(top.width() + top.x() - middle.x());
  56     top.set_x(middle.x());
  57   }
  58   if (top.right() >= middle.right() - 2 * margin) {
  59     top.set_width(middle.right() - top.x());
  60   }
  61
  62   if (bottom.x() <= middle.x() + 2 * margin) {
  63     bottom.set_width(bottom.width() + bottom.x() - middle.x());
  64     bottom.set_x(middle.x());
  65   }
  66   if (bottom.right() >= middle.right() - 2 * margin) {
  67     bottom.set_width(middle.right() - bottom.x());
  68   }
  69
  70   AccessibilityFocusRing ring;
  71   ring.points[0] = gfx::Point(top.x(), top.bottom() - margin);
  72   ring.points[1] = gfx::Point(top.x(), top.y() + margin);
  73   ring.points[2] = gfx::Point(top.x(), top.y());
  74   ring.points[3] = gfx::Point(top.x() + margin, top.y());
  75   ring.points[4] = gfx::Point(top.right() - margin, top.y());
  76   ring.points[5] = gfx::Point(top.right(), top.y());
  77   ring.points[6] = gfx::Point(top.right(), top.y() + margin);
  78   ring.points[7] = gfx::Point(top.right(), top.bottom() - margin);
  79   ring.points[8] = gfx::Point(top.right(), top.bottom());
  80   if (top.right() < middle.right()) {
  81     ring.points[9] = gfx::Point(top.right() + margin, middle.y());
  82     ring.points[10] = gfx::Point(middle.right() - margin, middle.y());
  83   } else {
  84     ring.points[9] = gfx::Point(top.right(), middle.y());
  85     ring.points[10] = gfx::Point(middle.right(), middle.y());
  86   }
  87   ring.points[11] = gfx::Point(middle.right(), middle.y());
  88   ring.points[12] = gfx::Point(middle.right(), middle.y() + margin);
  89   ring.points[13] = gfx::Point(middle.right(), middle.bottom() - margin);
  90   ring.points[14] = gfx::Point(middle.right(), middle.bottom());
  91   if (bottom.right() < middle.right()) {
  92     ring.points[15] = gfx::Point(middle.right() - margin, bottom.y());
  93     ring.points[16] = gfx::Point(bottom.right() + margin, bottom.y());
  94   } else {
  95     ring.points[15] = gfx::Point(middle.right(), bottom.y());
  96     ring.points[16] = gfx::Point(bottom.right(), bottom.y());
  97   }
  98   ring.points[17] = gfx::Point(bottom.right(), bottom.y());
  99   ring.points[18] = gfx::Point(bottom.right(), bottom.y() + margin);
 100   ring.points[19] = gfx::Point(bottom.right(), bottom.bottom() - margin);
 101   ring.points[20] = gfx::Point(bottom.right(), bottom.bottom());
 102   ring.points[21] = gfx::Point(bottom.right() - margin, bottom.bottom());
 103   ring.points[22] = gfx::Point(bottom.x() + margin, bottom.bottom());
 104   ring.points[23] = gfx::Point(bottom.x(), bottom.bottom());
 105   ring.points[24] = gfx::Point(bottom.x(), bottom.bottom() - margin);
 106   ring.points[25] = gfx::Point(bottom.x(), bottom.y() + margin);
 107   ring.points[26] = gfx::Point(bottom.x(), bottom.y());
 108   if (bottom.x() > middle.x()) {
 109     ring.points[27] = gfx::Point(bottom.x() - margin, bottom.y());
 110     ring.points[28] = gfx::Point(middle.x() + margin, middle.bottom());
 111   } else {
 112     ring.points[27] = gfx::Point(bottom.x(), bottom.y());
 113     ring.points[28] = gfx::Point(middle.x(), middle.bottom());
 114   }
 115   ring.points[29] = gfx::Point(middle.x(), middle.bottom());
 116   ring.points[30] = gfx::Point(middle.x(), middle.bottom() - margin);
 117   ring.points[31] = gfx::Point(middle.x(), middle.y() + margin);
 118   ring.points[32] = gfx::Point(middle.x(), middle.y());
 119   if (top.x() > middle.x()) {
 120     ring.points[33] = gfx::Point(middle.x() + margin, middle.y());
 121     ring.points[34] = gfx::Point(top.x() - margin, top.bottom());
 122   } else {
 123     ring.points[33] = gfx::Point(middle.x(), middle.y());
 124     ring.points[34] = gfx::Point(top.x(), top.bottom());
 125   }
 126   ring.points[35] = gfx::Point(top.x(), top.bottom());
 127
 128   return ring;
 129 }
 130
 131 gfx::Rect AccessibilityFocusRing::GetBounds() const {
 132   gfx::Point top_left = points[0];
 133   gfx::Point bottom_right = points[0];
 134   for (size_t i = 1; i < 36; ++i) {
 135     top_left.SetToMin(points[i]);
 136     bottom_right.SetToMax(points[i]);
 137   }
 138   return gfx::Rect(top_left, gfx::Size(bottom_right.x() - top_left.x(),
 139                                        bottom_right.y() - top_left.y()));
 140 }
 141
 142 }  // namespace chromeos