| /* |
| * Copyright (C) 1999 Lars Knoll (knoll@kde.org) |
| * (C) 2004-2005 Allan Sandfeld Jensen (kde@carewolf.com) |
| * Copyright (C) 2006, 2007 Nicholas Shanks (webkit@nickshanks.com) |
| * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 Apple Inc. |
| * All rights reserved. |
| * Copyright (C) 2007 Alexey Proskuryakov <ap@webkit.org> |
| * Copyright (C) 2007, 2008 Eric Seidel <eric@webkit.org> |
| * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. |
| * (http://www.torchmobile.com/) |
| * Copyright (c) 2011, Code Aurora Forum. All rights reserved. |
| * Copyright (C) Research In Motion Limited 2011. All rights reserved. |
| * Copyright (C) 2012 Google Inc. All rights reserved. |
| * |
| * This library is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Library General Public |
| * License as published by the Free Software Foundation; either |
| * version 2 of the License, or (at your option) any later version. |
| * |
| * This library is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Library General Public License for more details. |
| * |
| * You should have received a copy of the GNU Library General Public License |
| * along with this library; see the file COPYING.LIB. If not, write to |
| * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, |
| * Boston, MA 02110-1301, USA. |
| */ |
| |
| #include "core/css/FontSize.h" |
| |
| #include "core/CSSValueKeywords.h" |
| #include "core/dom/Document.h" |
| #include "core/frame/Settings.h" |
| |
| namespace blink { |
| |
| float FontSize::getComputedSizeFromSpecifiedSize( |
| const Document* document, |
| float zoomFactor, |
| bool isAbsoluteSize, |
| float specifiedSize, |
| ESmartMinimumForFontSize useSmartMinimumForFontSize) { |
| // Text with a 0px font size should not be visible and therefore needs to be |
| // exempt from minimum font size rules. Acid3 relies on this for pixel-perfect |
| // rendering. This is also compatible with other browsers that have minimum |
| // font size settings (e.g. Firefox). |
| if (fabsf(specifiedSize) < std::numeric_limits<float>::epsilon()) |
| return 0.0f; |
| |
| // We support two types of minimum font size. The first is a hard override |
| // that applies to all fonts. This is "minSize." The second type of minimum |
| // font size is a "smart minimum" that is applied only when the Web page can't |
| // know what size it really asked for, e.g., when it uses logical sizes like |
| // "small" or expresses the font-size as a percentage of the user's default |
| // font setting. |
| |
| // With the smart minimum, we never want to get smaller than the minimum font |
| // size to keep fonts readable. However we always allow the page to set an |
| // explicit pixel size that is smaller, since sites will mis-render otherwise |
| // (e.g., http://www.gamespot.com with a 9px minimum). |
| |
| Settings* settings = document->settings(); |
| if (!settings) |
| return 1.0f; |
| |
| int minSize = settings->minimumFontSize(); |
| int minLogicalSize = settings->minimumLogicalFontSize(); |
| float zoomedSize = specifiedSize * zoomFactor; |
| |
| // Apply the hard minimum first. We only apply the hard minimum if after |
| // zooming we're still too small. |
| if (zoomedSize < minSize) |
| zoomedSize = minSize; |
| |
| // Now apply the "smart minimum." This minimum is also only applied if we're |
| // still too small after zooming. The font size must either be relative to the |
| // user default or the original size must have been acceptable. In other |
| // words, we only apply the smart minimum whenever we're positive doing so |
| // won't disrupt the layout. |
| if (useSmartMinimumForFontSize && zoomedSize < minLogicalSize && |
| (specifiedSize >= minLogicalSize || !isAbsoluteSize)) |
| zoomedSize = minLogicalSize; |
| |
| // Also clamp to a reasonable maximum to prevent insane font sizes from |
| // causing crashes on various platforms (I'm looking at you, Windows.) |
| return std::min(maximumAllowedFontSize, zoomedSize); |
| } |
| |
| const int fontSizeTableMax = 16; |
| const int fontSizeTableMin = 9; |
| const int totalKeywords = 8; |
| |
| // WinIE/Nav4 table for font sizes. Designed to match the legacy font mapping |
| // system of HTML. |
| static const int quirksFontSizeTable[fontSizeTableMax - fontSizeTableMin + |
| 1][totalKeywords] = { |
| {9, 9, 9, 9, 11, 14, 18, 28}, {9, 9, 9, 10, 12, 15, 20, 31}, |
| {9, 9, 9, 11, 13, 17, 22, 34}, {9, 9, 10, 12, 14, 18, 24, 37}, |
| {9, 9, 10, 13, 16, 20, 26, 40}, // fixed font default (13) |
| {9, 9, 11, 14, 17, 21, 28, 42}, {9, 10, 12, 15, 17, 23, 30, 45}, |
| {9, 10, 13, 16, 18, 24, 32, 48} // proportional font default (16) |
| }; |
| // HTML 1 2 3 4 5 6 7 |
| // CSS xxs xs s m l xl xxl |
| // | |
| // user pref |
| |
| // Strict mode table matches MacIE and Mozilla's settings exactly. |
| static const int strictFontSizeTable[fontSizeTableMax - fontSizeTableMin + |
| 1][totalKeywords] = { |
| {9, 9, 9, 9, 11, 14, 18, 27}, {9, 9, 9, 10, 12, 15, 20, 30}, |
| {9, 9, 10, 11, 13, 17, 22, 33}, {9, 9, 10, 12, 14, 18, 24, 36}, |
| {9, 10, 12, 13, 16, 20, 26, 39}, // fixed font default (13) |
| {9, 10, 12, 14, 17, 21, 28, 42}, {9, 10, 13, 15, 18, 23, 30, 45}, |
| {9, 10, 13, 16, 18, 24, 32, 48} // proportional font default (16) |
| }; |
| // HTML 1 2 3 4 5 6 7 |
| // CSS xxs xs s m l xl xxl |
| // | |
| // user pref |
| |
| // For values outside the range of the table, we use Todd Fahrner's suggested |
| // scale factors for each keyword value. |
| static const float fontSizeFactors[totalKeywords] = {0.60f, 0.75f, 0.89f, 1.0f, |
| 1.2f, 1.5f, 2.0f, 3.0f}; |
| |
| static int inline rowFromMediumFontSizeInRange(const Settings* settings, |
| bool quirksMode, |
| bool isMonospace, |
| int& mediumSize) { |
| mediumSize = isMonospace ? settings->defaultFixedFontSize() |
| : settings->defaultFontSize(); |
| if (mediumSize >= fontSizeTableMin && mediumSize <= fontSizeTableMax) |
| return mediumSize - fontSizeTableMin; |
| return -1; |
| } |
| |
| float FontSize::fontSizeForKeyword(const Document* document, |
| unsigned keyword, |
| bool isMonospace) { |
| ASSERT(keyword >= 1 && keyword <= 8); |
| const Settings* settings = document->settings(); |
| if (!settings) |
| return 1.0f; |
| |
| bool quirksMode = document->inQuirksMode(); |
| int mediumSize = 0; |
| int row = rowFromMediumFontSizeInRange(settings, quirksMode, isMonospace, |
| mediumSize); |
| if (row >= 0) { |
| int col = (keyword - 1); |
| return quirksMode ? quirksFontSizeTable[row][col] |
| : strictFontSizeTable[row][col]; |
| } |
| |
| // Value is outside the range of the table. Apply the scale factor instead. |
| float minLogicalSize = std::max(settings->minimumLogicalFontSize(), 1); |
| return std::max(fontSizeFactors[keyword - 1] * mediumSize, minLogicalSize); |
| } |
| |
| template <typename T> |
| static int findNearestLegacyFontSize(int pixelFontSize, |
| const T* table, |
| int multiplier) { |
| // Ignore table[0] because xx-small does not correspond to any legacy font |
| // size. |
| for (int i = 1; i < totalKeywords - 1; i++) { |
| if (pixelFontSize * 2 < (table[i] + table[i + 1]) * multiplier) |
| return i; |
| } |
| return totalKeywords - 1; |
| } |
| |
| int FontSize::legacyFontSize(const Document* document, |
| int pixelFontSize, |
| bool isMonospace) { |
| const Settings* settings = document->settings(); |
| if (!settings) |
| return 1; |
| |
| bool quirksMode = document->inQuirksMode(); |
| int mediumSize = 0; |
| int row = rowFromMediumFontSizeInRange(settings, quirksMode, isMonospace, |
| mediumSize); |
| if (row >= 0) |
| return findNearestLegacyFontSize<int>( |
| pixelFontSize, |
| quirksMode ? quirksFontSizeTable[row] : strictFontSizeTable[row], 1); |
| |
| return findNearestLegacyFontSize<float>(pixelFontSize, fontSizeFactors, |
| mediumSize); |
| } |
| |
| } // namespace blink |
