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, 5 insertions, 4 deletions

diff --git a/src/gui/image/qpixmap_s60.cpp b/src/gui/image/qpixmap_s60.cpp
index cd8a4d4..6a999b4 100644
--- a/src/gui/image/qpixmap_s60.cpp
+++ b/src/gui/image/qpixmap_s60.cpp
@@ -568,6 +568,7 @@ int QS60PixmapData::metric(QPaintDevice::PaintDeviceMetric metric) const
     if (!cfbsBitmap)
         return 0;
 
+    qreal div_by_KTwipsPerInch = 1 / (qreal)KTwipsPerInch;
     switch (metric) {
     case QPaintDevice::PdmWidth:
         return cfbsBitmap->SizeInPixels().iWidth;
@@ -575,23 +576,23 @@ int QS60PixmapData::metric(QPaintDevice::PaintDeviceMetric metric) const
         return cfbsBitmap->SizeInPixels().iHeight;
     case QPaintDevice::PdmWidthMM: {
         TInt twips = cfbsBitmap->SizeInTwips().iWidth;
-        return (int)(twips * (25.4/KTwipsPerInch));
+        return (int)(twips * (qreal(25.4) * div_by_KTwipsPerInch));
     }
     case QPaintDevice::PdmHeightMM: {
         TInt twips = cfbsBitmap->SizeInTwips().iHeight;
-        return (int)(twips * (25.4/KTwipsPerInch));
+        return (int)(twips * (qreal(25.4) * div_by_KTwipsPerInch));
     }
     case QPaintDevice::PdmNumColors:
         return TDisplayModeUtils::NumDisplayModeColors(cfbsBitmap->DisplayMode());
     case QPaintDevice::PdmDpiX:
     case QPaintDevice::PdmPhysicalDpiX: {
-        TReal inches = cfbsBitmap->SizeInTwips().iWidth / (TReal)KTwipsPerInch;
+        qreal inches = cfbsBitmap->SizeInTwips().iWidth * div_by_KTwipsPerInch;
         TInt pixels = cfbsBitmap->SizeInPixels().iWidth;
         return pixels / inches;
     }
     case QPaintDevice::PdmDpiY:
     case QPaintDevice::PdmPhysicalDpiY: {
-        TReal inches = cfbsBitmap->SizeInTwips().iHeight / (TReal)KTwipsPerInch;
+        qreal inches = cfbsBitmap->SizeInTwips().iHeight * div_by_KTwipsPerInch;
         TInt pixels = cfbsBitmap->SizeInPixels().iHeight;
         return pixels / inches;
     }