chrome/browser/ui/tabs/tab_resources.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 "chrome/browser/ui/tabs/tab_resources.h"
   6
   7 #include "base/logging.h"
   8 #include "ui/gfx/path.h"
   9
  10 namespace {
  11
  12 // Hit mask constants.
  13 const SkScalar kTabCapWidth = 15;
  14 const SkScalar kTabTopCurveWidth = 4;
  15 const SkScalar kTabBottomCurveWidth = 3;
  16 #if defined(TOOLKIT_VIEWS)
  17 // Windows and Ash have shadows in the left, right and top parts of the tab.
  18 const SkScalar kTabInset = 6;
  19 const SkScalar kTabTop = 2;
  20 #else
  21 // Linux GTK and Mac don't have the shadows.
  22 const SkScalar kTabInset = 0;
  23 const SkScalar kTabTop = 0;
  24 #endif
  25
  26 }  // namespace
  27
  28 // static
  29 void TabResources::GetHitTestMask(int width,
  30                                   int height,
  31                                   bool include_top_shadow,
  32                                   gfx::Path* path) {
  33   DCHECK(path);
  34
  35   SkScalar left = kTabInset;
  36   SkScalar top = kTabTop;
  37   SkScalar right = SkIntToScalar(width) - kTabInset;
  38   SkScalar bottom = SkIntToScalar(height);
  39
  40   // Start in the lower-left corner.
  41   path->moveTo(left, bottom);
  42
  43   // Left end cap.
  44   path->lineTo(left + kTabBottomCurveWidth, bottom - kTabBottomCurveWidth);
  45   path->lineTo(left + kTabCapWidth - kTabTopCurveWidth,
  46                top + kTabTopCurveWidth);
  47   path->lineTo(left + kTabCapWidth, top);
  48
  49   // Extend over the top shadow area if we have one and the caller wants it.
  50   if (kTabTop > 0 && include_top_shadow) {
  51     path->lineTo(left + kTabCapWidth, 0);
  52     path->lineTo(right - kTabCapWidth, 0);
  53   }
  54
  55   // Connect to the right cap.
  56   path->lineTo(right - kTabCapWidth, top);
  57
  58   // Right end cap.
  59   path->lineTo(right - kTabCapWidth + kTabTopCurveWidth,
  60                top + kTabTopCurveWidth);
  61   path->lineTo(right - kTabBottomCurveWidth, bottom - kTabBottomCurveWidth);
  62   path->lineTo(right, bottom);
  63
  64   // Close out the path.
  65   path->lineTo(left, bottom);
  66   path->close();
  67 }