Using qreal more consistently in code (prevent misuse of double)

We want to force use of qreal where possible. This can lead to better
performance on platforms where qreal -> float (i.e. ARM). To achieve
this we:

1. changed from 'double' to 'qreal', where justified
2. using qreal() to intialize constants, where justified
3. adding helper functions that are overloaded for qreal
   like qAtan2(), qAcos(), qFabs() ...
4. defining QT_USE_MATH_H_FLOATS for Symbian platform

In addtion we used opportunity to improve code with some small things
5. converting divisions to multiplications
   (i.e. '/ 2.0' -> '* qreal(0.5)')
6. defining new constants (i.e. 'Q_PI / 180.0' -> 'Q_PI180')
7. declaring variables as 'const', where justified

Reviewed-by: Andreas Aardal Hanssen
Reviewed-by: Gunnar Sletta
Reviewed-by: Jan-Arve
Reviewed-by: Kim Motoyoshi Kalland
Reviewed-by: Alessandro Portale
Reviewed-by: Janne Koskinen

1 files changed, 2 insertions, 2 deletions

diff --git a/src/corelib/global/qglobal.h b/src/corelib/global/qglobal.h
index 9558256..6befb33 100644
--- a/src/corelib/global/qglobal.h
+++ b/src/corelib/global/qglobal.h
@@ -1081,14 +1081,14 @@ template <typename T>
 inline T qAbs(const T &t) { return t >= 0 ? t : -t; }
 
 inline int qRound(qreal d)
-{ return d >= 0.0 ? int(d + 0.5) : int(d - int(d-1) + 0.5) + int(d-1); }
+{ return d >= qreal(0.0) ? int(d + qreal(0.5)) : int(d - int(d-1) + qreal(0.5)) + int(d-1); }
 
 #if defined(QT_NO_FPU) || defined(QT_ARCH_ARM) || defined(QT_ARCH_WINDOWSCE) || defined(QT_ARCH_SYMBIAN)
 inline qint64 qRound64(double d)
 { return d >= 0.0 ? qint64(d + 0.5) : qint64(d - qreal(qint64(d-1)) + 0.5) + qint64(d-1); }
 #else
 inline qint64 qRound64(qreal d)
-{ return d >= 0.0 ? qint64(d + 0.5) : qint64(d - qreal(qint64(d-1)) + 0.5) + qint64(d-1); }
+{ return d >= 0.0 ? qint64(d + qreal(0.5)) : qint64(d - qreal(qint64(d-1)) + qreal(0.5)) + qint64(d-1); }
 #endif
 
 template <typename T>