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 #ifndef CONTENT_PUBLIC_COMMON_PAGE_ZOOM_H_ 6 #define CONTENT_PUBLIC_COMMON_PAGE_ZOOM_H_ 7 8 #include "content/common/content_export.h" 9 10 namespace content { 11 12 // This enum is the parameter to various text/page zoom commands so we know 13 // what the specific zoom command is. 14 enum PageZoom { 15 PAGE_ZOOM_OUT = -1, 16 PAGE_ZOOM_RESET = 0, 17 PAGE_ZOOM_IN = 1, 18 }; 19 20 // The minimum zoom factor permitted for a page. This is an alternative to 21 // WebView::minTextSizeMultiplier. 22 CONTENT_EXPORT extern const double kMinimumZoomFactor; 23 24 // The maximum zoom factor permitted for a page. This is an alternative to 25 // WebView::maxTextSizeMultiplier. 26 CONTENT_EXPORT extern const double kMaximumZoomFactor; 27 28 // Epsilon value for comparing two floating-point zoom values. We don't use 29 // std::numeric_limits<> because it is too precise for zoom values. Zoom 30 // values lose precision due to factor/level conversions. A value of 0.001 31 // is precise enough for zoom value comparisons. 32 CONTENT_EXPORT extern const double kEpsilon; 33 34 // Test if two zoom values (either zoom factors or zoom levels) should be 35 // considered equal. 36 CONTENT_EXPORT bool ZoomValuesEqual(double value_a, double value_b); 37 38 // Converts between zoom factors and levels. 39 CONTENT_EXPORT double ZoomLevelToZoomFactor(double zoom_level); 40 CONTENT_EXPORT double ZoomFactorToZoomLevel(double factor); 41 42 } // namespace content 43 44 #endif // CONTENT_PUBLIC_COMMON_PAGE_ZOOM_H_ 45
