// Copyright (c) 2011 The Chromium Authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. #include <cmath> #include "content/public/common/page_zoom.h" namespace content { const double kMinimumZoomFactor = 0.25; const double kMaximumZoomFactor = 5.0; const double kEpsilon = 0.001; const double kTextSizeMultiplierRatio = 1.2; bool ZoomValuesEqual(double value_a, double value_b) { return (std::fabs(value_a - value_b) <= kEpsilon); } double ZoomLevelToZoomFactor(double zoom_level) { return std::pow(kTextSizeMultiplierRatio, zoom_level); } double ZoomFactorToZoomLevel(double factor) { return std::log(factor) / std::log(kTextSizeMultiplierRatio); } } // namespace content