1 /****************************************************************************

     2 **

     3 ** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).

     4 ** All rights reserved.

     5 ** Contact: Nokia Corporation (qt-info@nokia.com)

     6 **

     7 ** This file is part of the QtCore module of the Qt Toolkit.

     8 **

     9 ** $QT_BEGIN_LICENSE:LGPL$

    10 ** No Commercial Usage

    11 ** This file contains pre-release code and may not be distributed.

    12 ** You may use this file in accordance with the terms and conditions

    13 ** contained in the Technology Preview License Agreement accompanying

    14 ** this package.

    15 **

    16 ** GNU Lesser General Public License Usage

    17 ** Alternatively, this file may be used under the terms of the GNU Lesser

    18 ** General Public License version 2.1 as published by the Free Software

    19 ** Foundation and appearing in the file LICENSE.LGPL included in the

    20 ** packaging of this file.  Please review the following information to

    21 ** ensure the GNU Lesser General Public License version 2.1 requirements

    22 ** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.

    23 **

    24 ** In addition, as a special exception, Nokia gives you certain additional

    25 ** rights.  These rights are described in the Nokia Qt LGPL Exception

    26 ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.

    27 **

    28 ** If you have questions regarding the use of this file, please contact

    29 ** Nokia at qt-info@nokia.com.

    30 **

    31 **

    32 **

    33 **

    34 **

    35 **

    36 **

    37 **

    38 ** $QT_END_LICENSE$

    39 **

    40 ****************************************************************************/

    41 

    42 #ifndef QMATH_H

    43 #define QMATH_H

    44 

    45 #include <math.h>

    46 

    47 #include <QtCore/qglobal.h>

    48 

    49 QT_BEGIN_HEADER

    50 

    51 QT_BEGIN_NAMESPACE

    52 

    53 QT_MODULE(Core)

    54 

    55 #define QT_SINE_TABLE_SIZE 256

    56 

    57 extern Q_CORE_EXPORT const qreal qt_sine_table[QT_SINE_TABLE_SIZE];

    58 

    59 inline int qCeil(qreal v)

    60 {

    61 #ifdef QT_USE_MATH_H_FLOATS

    62     if (sizeof(qreal) == sizeof(float))

    63         return int(ceilf(float(v)));

    64     else

    65 #endif

    66         return int(ceil(v));

    67 }

    68 

    69 inline int qFloor(qreal v)

    70 {

    71 #ifdef QT_USE_MATH_H_FLOATS

    72     if (sizeof(qreal) == sizeof(float))

    73         return int(floorf(float(v)));

    74     else

    75 #endif

    76         return int(floor(v));

    77 }

    78 

    79 inline qreal qSin(qreal v)

    80 {

    81 #ifdef QT_USE_MATH_H_FLOATS

    82     if (sizeof(qreal) == sizeof(float))

    83         return sinf(float(v));

    84     else

    85 #endif

    86         return sin(v);

    87 }

    88 

    89 inline qreal qCos(qreal v)

    90 {

    91 #ifdef QT_USE_MATH_H_FLOATS

    92     if (sizeof(qreal) == sizeof(float))

    93         return cosf(float(v));

    94     else

    95 #endif

    96         return cos(v);

    97 }

    98 

    99 inline qreal qAcos(qreal v)

   100 {

   101 #ifdef QT_USE_MATH_H_FLOATS

   102     if (sizeof(qreal) == sizeof(float))

   103         return acosf(float(v));

   104     else

   105 #endif

   106         return acos(v);

   107 }

   108 

   109 inline qreal qSqrt(qreal v)

   110 {

   111 #ifdef QT_USE_MATH_H_FLOATS

   112     if (sizeof(qreal) == sizeof(float))

   113         return sqrtf(float(v));

   114     else

   115 #endif

   116         return sqrt(v);

   117 }

   118 

   119 inline qreal qLn(qreal v)

   120 {

   121 #ifdef QT_USE_MATH_H_FLOATS

   122     if (sizeof(qreal) == sizeof(float))

   123         return logf(float(v));

   124     else

   125 #endif

   126         return log(v);

   127 }

   128 

   129 inline qreal qPow(qreal x, qreal y)

   130 {

   131 #ifdef QT_USE_MATH_H_FLOATS

   132     if (sizeof(qreal) == sizeof(float))

   133         return powf(float(x), float(y));

   134     else

   135 #endif

   136         return pow(x, y);

   137 }

   138 

   139 #ifndef M_PI

   140 #define M_PI (3.14159265358979323846)

   141 #endif

   142 

   143 inline qreal qFastSin(qreal x)

   144 {

   145     int si = int(x * (0.5 * QT_SINE_TABLE_SIZE / M_PI)); // Would be more accurate with qRound, but slower.

   146     qreal d = x - si * (2.0 * M_PI / QT_SINE_TABLE_SIZE);

   147     int ci = si + QT_SINE_TABLE_SIZE / 4;

   148     si &= QT_SINE_TABLE_SIZE - 1;

   149     ci &= QT_SINE_TABLE_SIZE - 1;

   150     return qt_sine_table[si] + (qt_sine_table[ci] - 0.5 * qt_sine_table[si] * d) * d;

   151 }

   152 

   153 inline qreal qFastCos(qreal x)

   154 {

   155     int ci = int(x * (0.5 * QT_SINE_TABLE_SIZE / M_PI)); // Would be more accurate with qRound, but slower.

   156     qreal d = x - ci * (2.0 * M_PI / QT_SINE_TABLE_SIZE);

   157     int si = ci + QT_SINE_TABLE_SIZE / 4;

   158     si &= QT_SINE_TABLE_SIZE - 1;

   159     ci &= QT_SINE_TABLE_SIZE - 1;

   160     return qt_sine_table[si] - (qt_sine_table[ci] + 0.5 * qt_sine_table[si] * d) * d;

   161 }

   162 

   163 QT_END_NAMESPACE

   164 

   165 QT_END_HEADER

   166 

   167 #endif // QMATH_H