Home | History | Annotate | Download | only in platform 
      1 /*
      2  * Copyright (C) 2011 Google Inc. All rights reserved.
      3  *
      4  * Redistribution and use in source and binary forms, with or without
      5  * modification, are permitted provided that the following conditions are
      6  * met:
      7  *
      8  *     * Redistributions of source code must retain the above copyright
      9  * notice, this list of conditions and the following disclaimer.
     10  *     * Redistributions in binary form must reproduce the above
     11  * copyright notice, this list of conditions and the following disclaimer
     12  * in the documentation and/or other materials provided with the
     13  * distribution.
     14  *     * Neither the name of Google Inc. nor the names of its
     15  * contributors may be used to endorse or promote products derived from
     16  * this software without specific prior written permission.
     17  *
     18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     21  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
     22  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     23  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
     24  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     28  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     29  */
     30 
     31 #ifndef CalculationValue_h
     32 #define CalculationValue_h
     33 
     34 #include "core/css/LengthFunctions.h"
     35 #include "core/platform/Length.h"
     36 #include "wtf/OwnPtr.h"
     37 #include "wtf/PassOwnPtr.h"
     38 #include "wtf/RefCounted.h"
     39 #include "wtf/Vector.h"
     40 
     41 namespace WebCore {
     42 
     43 enum CalcOperator {
     44     CalcAdd = '+',
     45     CalcSubtract = '-',
     46     CalcMultiply = '*',
     47     CalcDivide = '/'
     48 };
     49 
     50 enum CalculationPermittedValueRange {
     51     CalculationRangeAll,
     52     CalculationRangeNonNegative
     53 };
     54 
     55 enum CalcExpressionNodeType {
     56     CalcExpressionNodeUndefined,
     57     CalcExpressionNodeNumber,
     58     CalcExpressionNodeLength,
     59     CalcExpressionNodeBinaryOperation,
     60     CalcExpressionNodeBlendLength,
     61 };
     62 
     63 class CalcExpressionNode {
     64     WTF_MAKE_FAST_ALLOCATED;
     65 public:
     66     CalcExpressionNode()
     67         : m_type(CalcExpressionNodeUndefined)
     68     {
     69     }
     70 
     71     virtual ~CalcExpressionNode()
     72     {
     73     }
     74 
     75     virtual float evaluate(float maxValue) const = 0;
     76     virtual bool operator==(const CalcExpressionNode&) const = 0;
     77 
     78     CalcExpressionNodeType type() const { return m_type; }
     79 
     80 protected:
     81     CalcExpressionNodeType m_type;
     82 };
     83 
     84 class CalculationValue : public RefCounted<CalculationValue> {
     85 public:
     86     static PassRefPtr<CalculationValue> create(PassOwnPtr<CalcExpressionNode> value, CalculationPermittedValueRange);
     87     float evaluate(float maxValue) const;
     88 
     89     bool operator==(const CalculationValue& o) const
     90     {
     91         return *(m_value.get()) == *(o.m_value.get());
     92     }
     93 
     94 private:
     95     CalculationValue(PassOwnPtr<CalcExpressionNode> value, CalculationPermittedValueRange range)
     96         : m_value(value)
     97         , m_isNonNegative(range == CalculationRangeNonNegative)
     98     {
     99     }
    100 
    101     OwnPtr<CalcExpressionNode> m_value;
    102     bool m_isNonNegative;
    103 };
    104 
    105 class CalcExpressionNumber : public CalcExpressionNode {
    106 public:
    107     explicit CalcExpressionNumber(float value)
    108         : m_value(value)
    109     {
    110         m_type = CalcExpressionNodeNumber;
    111     }
    112 
    113     bool operator==(const CalcExpressionNumber& o) const
    114     {
    115         return m_value == o.m_value;
    116     }
    117 
    118     virtual bool operator==(const CalcExpressionNode& o) const
    119     {
    120         return type() == o.type() && *this == static_cast<const CalcExpressionNumber&>(o);
    121     }
    122 
    123     virtual float evaluate(float) const
    124     {
    125         return m_value;
    126     }
    127 
    128 private:
    129     float m_value;
    130 };
    131 
    132 class CalcExpressionLength : public CalcExpressionNode {
    133 public:
    134     explicit CalcExpressionLength(Length length)
    135         : m_length(length)
    136     {
    137         m_type = CalcExpressionNodeLength;
    138     }
    139 
    140     bool operator==(const CalcExpressionLength& o) const
    141     {
    142         return m_length == o.m_length;
    143     }
    144 
    145     virtual bool operator==(const CalcExpressionNode& o) const
    146     {
    147         return type() == o.type() && *this == static_cast<const CalcExpressionLength&>(o);
    148     }
    149 
    150     virtual float evaluate(float maxValue) const
    151     {
    152         return floatValueForLength(m_length, maxValue);
    153     }
    154 
    155 private:
    156     Length m_length;
    157 };
    158 
    159 class CalcExpressionBinaryOperation : public CalcExpressionNode {
    160 public:
    161     CalcExpressionBinaryOperation(PassOwnPtr<CalcExpressionNode> leftSide, PassOwnPtr<CalcExpressionNode> rightSide, CalcOperator op)
    162         : m_leftSide(leftSide)
    163         , m_rightSide(rightSide)
    164         , m_operator(op)
    165     {
    166         m_type = CalcExpressionNodeBinaryOperation;
    167     }
    168 
    169     bool operator==(const CalcExpressionBinaryOperation& o) const
    170     {
    171         return m_operator == o.m_operator && *m_leftSide == *o.m_leftSide && *m_rightSide == *o.m_rightSide;
    172     }
    173 
    174     virtual bool operator==(const CalcExpressionNode& o) const
    175     {
    176         return type() == o.type() && *this == static_cast<const CalcExpressionBinaryOperation&>(o);
    177     }
    178 
    179 
    180     virtual float evaluate(float) const;
    181 
    182 private:
    183     OwnPtr<CalcExpressionNode> m_leftSide;
    184     OwnPtr<CalcExpressionNode> m_rightSide;
    185     CalcOperator m_operator;
    186 };
    187 
    188 class CalcExpressionBlendLength : public CalcExpressionNode {
    189 public:
    190     CalcExpressionBlendLength(Length from, Length to, float progress)
    191         : m_from(from)
    192         , m_to(to)
    193         , m_progress(progress)
    194     {
    195         m_type = CalcExpressionNodeBlendLength;
    196     }
    197 
    198     bool operator==(const CalcExpressionBlendLength& o) const
    199     {
    200         return m_progress == o.m_progress && m_from == o.m_from && m_to == o.m_to;
    201     }
    202 
    203     virtual bool operator==(const CalcExpressionNode& o) const
    204     {
    205         return type() == o.type() && *this == static_cast<const CalcExpressionBlendLength&>(o);
    206     }
    207 
    208     virtual float evaluate(float maxValue) const
    209     {
    210         return (1.0f - m_progress) * floatValueForLength(m_from, maxValue) + m_progress * floatValueForLength(m_to, maxValue);
    211     }
    212 
    213 private:
    214     Length m_from;
    215     Length m_to;
    216     float m_progress;
    217 };
    218 
    219 } // namespace WebCore
    220 
    221 #endif // CalculationValue_h
    222