third_party/WebKit/Source/platform/CalculationValue.h

   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 "platform/Length.h"
  35 #include "platform/LengthFunctions.h"
  36 #include "wtf/OwnPtr.h"
  37 #include "wtf/PassOwnPtr.h"
  38 #include "wtf/RefCounted.h"
  39
  40 namespace blink {
  41
  42 class PLATFORM_EXPORT CalculationValue : public RefCounted<CalculationValue> {
  43 public:
  44     static PassRefPtr<CalculationValue> create(PixelsAndPercent value, ValueRange range)
  45     {
  46         return adoptRef(new CalculationValue(value, range));
  47     }
  48
  49     float evaluate(float maxValue) const
  50     {
  51         float value = pixels() + percent() / 100 * maxValue;
  52         return (isNonNegative() && value < 0) ? 0 : value;
  53     }
  54     bool operator==(const CalculationValue& o) const { return pixels() == o.pixels() && percent() == o.percent(); }
  55     bool isNonNegative() const { return m_isNonNegative; }
  56     ValueRange valueRange() const { return m_isNonNegative ? ValueRangeNonNegative : ValueRangeAll; }
  57     float pixels() const { return m_value.pixels; }
  58     float percent() const { return m_value.percent; }
  59     PixelsAndPercent pixelsAndPercent() const { return m_value; }
  60
  61 private:
  62     CalculationValue(PixelsAndPercent value, ValueRange range)
  63         : m_value(value)
  64         , m_isNonNegative(range == ValueRangeNonNegative)
  65     {
  66     }
  67
  68     PixelsAndPercent m_value;
  69     bool m_isNonNegative;
  70 };
  71
  72 } // namespace blink
  73
  74 #endif // CalculationValue_h