ui/views/shadow_border.cc

   1 // Copyright 2013 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 "ui/views/shadow_border.h"
   6
   7 #include "ui/gfx/canvas.h"
   8 #include "ui/gfx/insets.h"
   9 #include "ui/gfx/rect.h"
  10 #include "ui/gfx/shadow_value.h"
  11 #include "ui/gfx/skia_util.h"
  12 #include "ui/views/view.h"
  13
  14 namespace views {
  15
  16 ShadowBorder::ShadowBorder(int blur,
  17                            SkColor color,
  18                            int vertical_offset,
  19                            int horizontal_offset)
  20     : views::Border(),
  21       blur_(blur),
  22       color_(color),
  23       vertical_offset_(vertical_offset),
  24       horizontal_offset_(horizontal_offset) {}
  25
  26 ShadowBorder::~ShadowBorder() {}
  27
  28 // TODO(sidharthms): Re-painting a shadow looper on every paint call may yield
  29 // poor performance. Ideally we should be caching the border to bitmaps.
  30 void ShadowBorder::Paint(const views::View& view, gfx::Canvas* canvas) {
  31   SkPaint paint;
  32   std::vector<gfx::ShadowValue> shadows;
  33   shadows.push_back(gfx::ShadowValue(gfx::Point(), blur_, color_));
  34   skia::RefPtr<SkDrawLooper> looper = gfx::CreateShadowDrawLooper(shadows);
  35   paint.setLooper(looper.get());
  36   paint.setColor(SK_ColorTRANSPARENT);
  37   paint.setStrokeJoin(SkPaint::kRound_Join);
  38   gfx::Rect bounds(view.size());
  39   // TODO(pkasting): This isn't right if one of the offsets is larger than
  40   // (blur_ / 2).
  41   bounds.Inset(gfx::Insets(blur_ / 2, blur_ / 2, blur_ / 2, blur_ / 2));
  42   canvas->DrawRect(bounds, paint);
  43 }
  44
  45 gfx::Insets ShadowBorder::GetInsets() const {
  46   return gfx::Insets(blur_ / 2 - vertical_offset_,
  47                      blur_ / 2 - horizontal_offset_,
  48                      blur_ / 2 + vertical_offset_,
  49                      blur_ / 2 + horizontal_offset_);
  50 }
  51
  52 gfx::Size ShadowBorder::GetMinimumSize() const {
  53   return gfx::Size(blur_, blur_);
  54 }
  55
  56 }  // namespace views