Use C++ <cmath> instead of <math.h>

Including math.h can pollute the default namespace, and break
some compilers if cmath versions of the method are declared as using.

Switching to C++ math functions also greatly simplifies handling of
float qreal as C++ automatically chooses the right method.

[ChangeLog][QtCore][QtMath] qmath.h no longer includes math.h, so any
sources depending on that indirect inclusion may fail to build.

Change-Id: I4d0e331dafba354ec05dc5052e61ef4ff8d387fe
Reviewed-by: Rafael Roquetto <rafael.roquetto@kdab.com>

1 files changed, 3 insertions, 2 deletions

diff --git a/examples/widgets/effects/blurpicker/blurpicker.cpp b/examples/widgets/effects/blurpicker/blurpicker.cpp
index f354a15c53..b5ac7950bd 100644
--- a/examples/widgets/effects/blurpicker/blurpicker.cpp
+++ b/examples/widgets/effects/blurpicker/blurpicker.cpp
@@ -41,6 +41,7 @@
 #include "blurpicker.h"
 
 #include <QtWidgets>
+#include <QtCore/qmath.h>
 
 #include "blureffect.h"
 
@@ -76,8 +77,8 @@ void BlurPicker::setIndex(qreal index)
     for (int i = 0; i < m_icons.count(); ++i) {
         QGraphicsItem *icon = m_icons[i];
         qreal a = ((i + m_index) * 2 * M_PI) / m_icons.count();
-        qreal xs = 170 * sin(a);
-        qreal ys = 100 * cos(a);
+        qreal xs = 170 * qSin(a);
+        qreal ys = 100 * qCos(a);
         QPointF pos(xs, ys);
         pos = QTransform().rotate(-20).map(pos);
         pos -= QPointF(40, 40);