1 /* 2 Copyright (C) 1999 Lars Knoll (knoll (at) kde.org) 3 Copyright (C) 2006, 2008 Apple Inc. All rights reserved. 4 5 This library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Library General Public 7 License as published by the Free Software Foundation; either 8 version 2 of the License, or (at your option) any later version. 9 10 This library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Library General Public License for more details. 14 15 You should have received a copy of the GNU Library General Public License 16 along with this library; see the file COPYING.LIB. If not, write to 17 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 18 Boston, MA 02110-1301, USA. 19 */ 20 21 #ifndef Length_h 22 #define Length_h 23 24 #include <wtf/Assertions.h> 25 #include <wtf/FastAllocBase.h> 26 #include <wtf/MathExtras.h> 27 28 namespace WebCore { 29 30 class String; 31 32 const int undefinedLength = -1; 33 const int percentScaleFactor = 128; 34 35 enum LengthType { Auto, Relative, Percent, Fixed, Static, Intrinsic, MinIntrinsic }; 36 37 struct Length : FastAllocBase { 38 Length() 39 : m_value(0) 40 { 41 } 42 43 Length(LengthType t) 44 : m_value(t) 45 { 46 } 47 48 Length(int v, LengthType t, bool q = false) 49 : m_value((v * 16) | (q << 3) | t) // FIXME: Doesn't work if the passed-in value is very large! 50 { 51 ASSERT(t != Percent); 52 } 53 54 Length(double v, LengthType t, bool q = false) 55 : m_value(static_cast<int>(v * percentScaleFactor) * 16 | (q << 3) | t) 56 { 57 ASSERT(t == Percent); 58 } 59 60 bool operator==(const Length& o) const { return m_value == o.m_value; } 61 bool operator!=(const Length& o) const { return m_value != o.m_value; } 62 63 int value() const { 64 ASSERT(type() != Percent); 65 return rawValue(); 66 } 67 68 int rawValue() const { return (m_value & ~0xF) / 16; } 69 70 double percent() const 71 { 72 ASSERT(type() == Percent); 73 return static_cast<double>(rawValue()) / percentScaleFactor; 74 } 75 76 LengthType type() const { return static_cast<LengthType>(m_value & 7); } 77 bool quirk() const { return (m_value >> 3) & 1; } 78 79 void setValue(LengthType t, int value) 80 { 81 ASSERT(t != Percent); 82 setRawValue(t, value); 83 } 84 85 void setRawValue(LengthType t, int value) { m_value = value * 16 | (m_value & 0x8) | t; } 86 87 void setValue(int value) 88 { 89 ASSERT(!value || type() != Percent); 90 setRawValue(value); 91 } 92 93 void setRawValue(int value) { m_value = value * 16 | (m_value & 0xF); } 94 95 void setValue(LengthType t, double value) 96 { 97 ASSERT(t == Percent); 98 m_value = static_cast<int>(value * percentScaleFactor) * 16 | (m_value & 0x8) | t; 99 } 100 101 void setValue(double value) 102 { 103 ASSERT(type() == Percent); 104 m_value = static_cast<int>(value * percentScaleFactor) * 16 | (m_value & 0xF); 105 } 106 107 // note: works only for certain types, returns undefinedLength otherwise 108 int calcValue(int maxValue, bool roundPercentages = false) const 109 { 110 switch (type()) { 111 case Fixed: 112 return value(); 113 case Percent: 114 if (roundPercentages) 115 return static_cast<int>(round(maxValue * percent() / 100.0)); 116 return maxValue * rawValue() / (100 * percentScaleFactor); 117 case Auto: 118 return maxValue; 119 default: 120 return undefinedLength; 121 } 122 } 123 124 int calcMinValue(int maxValue, bool roundPercentages = false) const 125 { 126 switch (type()) { 127 case Fixed: 128 return value(); 129 case Percent: 130 if (roundPercentages) 131 return static_cast<int>(round(maxValue * percent() / 100.0)); 132 return maxValue * rawValue() / (100 * percentScaleFactor); 133 case Auto: 134 default: 135 return 0; 136 } 137 } 138 139 float calcFloatValue(int maxValue) const 140 { 141 switch (type()) { 142 case Fixed: 143 return static_cast<float>(value()); 144 case Percent: 145 return static_cast<float>(maxValue * percent() / 100.0); 146 case Auto: 147 return static_cast<float>(maxValue); 148 default: 149 return static_cast<float>(undefinedLength); 150 } 151 } 152 153 bool isUndefined() const { return rawValue() == undefinedLength; } 154 bool isZero() const { return !(m_value & ~0xF); } 155 bool isPositive() const { return rawValue() > 0; } 156 bool isNegative() const { return rawValue() < 0; } 157 158 bool isAuto() const { return type() == Auto; } 159 bool isRelative() const { return type() == Relative; } 160 bool isPercent() const { return type() == Percent; } 161 bool isFixed() const { return type() == Fixed; } 162 bool isStatic() const { return type() == Static; } 163 bool isIntrinsicOrAuto() const { return type() == Auto || type() == MinIntrinsic || type() == Intrinsic; } 164 165 Length blend(const Length& from, double progress) const 166 { 167 // Blend two lengths to produce a new length that is in between them. Used for animation. 168 if (!from.isZero() && !isZero() && from.type() != type()) 169 return *this; 170 171 if (from.isZero() && isZero()) 172 return *this; 173 174 LengthType resultType = type(); 175 if (isZero()) 176 resultType = from.type(); 177 178 if (resultType == Percent) { 179 double fromPercent = from.isZero() ? 0. : from.percent(); 180 double toPercent = isZero() ? 0. : percent(); 181 return Length(fromPercent + (toPercent - fromPercent) * progress, Percent); 182 } 183 184 int fromValue = from.isZero() ? 0 : from.value(); 185 int toValue = isZero() ? 0 : value(); 186 return Length(int(fromValue + (toValue - fromValue) * progress), resultType); 187 } 188 189 private: 190 int m_value; 191 }; 192 193 Length* newCoordsArray(const String&, int& len); 194 Length* newLengthArray(const String&, int& len); 195 196 } // namespace WebCore 197 198 #endif // Length_h 199
