components/favicon_base/fallback_icon_style.cc

   1 // Copyright 2015 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 "components/favicon_base/fallback_icon_style.h"
   6
   7 #include "ui/gfx/color_utils.h"
   8
   9 namespace favicon_base {
  10
  11 namespace {
  12
  13 // Luminance threshold for background color determine whether to use dark or
  14 // light text color.
  15 int kDarkTextLuminanceThreshold = 190;
  16
  17 // Default values for FallbackIconStyle.
  18 SkColor kDefaultBackgroundColor = SkColorSetRGB(0x80, 0x80, 0x80);
  19 SkColor kDefaultTextColorDark = SK_ColorBLACK;
  20 SkColor kDefaultTextColorLight = SK_ColorWHITE;
  21 double kDefaultFontSizeRatio = 0.8;
  22 double kDefaultRoundness = 0.125;  // 1 / 8.
  23
  24 }  // namespace
  25
  26 FallbackIconStyle::FallbackIconStyle()
  27     : background_color(kDefaultBackgroundColor),
  28       text_color(kDefaultTextColorLight),
  29       font_size_ratio(kDefaultFontSizeRatio),
  30       roundness(kDefaultRoundness) {
  31 }
  32
  33 FallbackIconStyle::~FallbackIconStyle() {
  34 }
  35
  36 void MatchFallbackIconTextColorAgainstBackgroundColor(
  37     FallbackIconStyle* style) {
  38   int luminance = color_utils::GetLuminanceForColor(style->background_color);
  39   style->text_color = (luminance >= kDarkTextLuminanceThreshold ?
  40       kDefaultTextColorDark : kDefaultTextColorLight);
  41 }
  42
  43 bool ValidateFallbackIconStyle(const FallbackIconStyle& style) {
  44   return style.font_size_ratio >= 0.0 && style.font_size_ratio <= 1.0 &&
  45       style.roundness >= 0.0 && style.roundness <= 1.0;
  46 }
  47
  48 }  // namespace favicon_base