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/shadow_value.h"
  10 #include "ui/gfx/skia_util.h"
  11
  12 namespace views {
  13
  14 ShadowBorder::ShadowBorder(int blur,
  15                            SkColor color,
  16                            int vertical_offset,
  17                            int horizontal_offset)
  18     : views::Border(),
  19       blur_(blur),
  20       color_(color),
  21       vertical_offset_(vertical_offset),
  22       horizontal_offset_(horizontal_offset) {}
  23
  24 ShadowBorder::~ShadowBorder() {}
  25
  26 // TODO(sidharthms): Re-painting a shadow looper on every paint call may yield
  27 // poor performance. Ideally we should be caching the border to bitmaps.
  28 void ShadowBorder::Paint(const views::View& view, gfx::Canvas* canvas) {
  29   SkPaint paint;
  30   std::vector<gfx::ShadowValue> shadows;
  31   shadows.push_back(gfx::ShadowValue(gfx::Point(), blur_, color_));
  32   skia::RefPtr<SkDrawLooper> looper = gfx::CreateShadowDrawLooper(shadows);
  33   paint.setLooper(looper.get());
  34   paint.setColor(SK_ColorTRANSPARENT);
  35   paint.setStrokeJoin(SkPaint::kRound_Join);
  36   gfx::Rect bounds(view.size());
  37   bounds.Inset(gfx::Insets(blur_ / 2, blur_ / 2, blur_ / 2, blur_ / 2));
  38   canvas->DrawRect(bounds, paint);
  39 }
  40
  41 gfx::Insets ShadowBorder::GetInsets() const {
  42   return gfx::Insets(blur_ / 2 - vertical_offset_,
  43                      blur_ / 2 - horizontal_offset_,
  44                      blur_ / 2 + vertical_offset_,
  45                      blur_ / 2 + horizontal_offset_);
  46 }
  47
  48 }  // namespace views