2 * Copyright (C) 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
14 * You should have received a copy of the GNU Library General Public License
15 * along with this library; see the file COPYING.LIB. If not, write to
16 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
17 * Boston, MA 02110-1301, USA.
24 #include <wtf/Forward.h>
25 #include <wtf/Noncopyable.h>
29 class HTMLInputElement;
32 WTF_MAKE_NONCOPYABLE(StepRange);
37 double maximum; // maximum must be >= minimum.
39 explicit StepRange(const HTMLInputElement*);
40 double clampValue(double value);
41 double clampValue(const String& stringValue);
43 // Clamp the middle value according to the step
46 return clampValue((minimum + maximum) / 2);
49 // Map value into 0-1 range
50 double proportionFromValue(double value)
52 if (minimum == maximum)
55 return (value - minimum) / (maximum - minimum);
58 // Map from 0-1 range to value
59 double valueFromProportion(double proportion)
61 return minimum + proportion * (maximum - minimum);
64 double valueFromElement(HTMLInputElement*, bool* wasClamped = 0);