diff options
Diffstat (limited to 'examples/touch/pinchzoom/mouse.cpp')
| -rw-r--r-- | examples/touch/pinchzoom/mouse.cpp | 15 |
1 files changed, 5 insertions, 10 deletions
diff --git a/examples/touch/pinchzoom/mouse.cpp b/examples/touch/pinchzoom/mouse.cpp index f063e96654..7f8c238e6f 100644 --- a/examples/touch/pinchzoom/mouse.cpp +++ b/examples/touch/pinchzoom/mouse.cpp @@ -53,11 +53,10 @@ #include <QGraphicsScene> #include <QPainter> #include <QStyleOption> +#include <qmath.h> -#include <math.h> - -static const double Pi = 3.14159265358979323846264338327950288419717; -static double TwoPi = 2.0 * Pi; +const qreal Pi = M_PI; +const qreal TwoPi = 2 * M_PI; static qreal normalizeAngle(qreal angle) { @@ -139,9 +138,7 @@ void Mouse::timerEvent(QTimerEvent *) //! [5] QLineF lineToCenter(QPointF(0, 0), mapFromScene(0, 0)); if (lineToCenter.length() > 150) { - qreal angleToCenter = ::acos(lineToCenter.dx() / lineToCenter.length()); - if (lineToCenter.dy() < 0) - angleToCenter = TwoPi - angleToCenter; + qreal angleToCenter = std::atan2(lineToCenter.dy(), lineToCenter.dx()); angleToCenter = normalizeAngle((Pi - angleToCenter) + Pi / 2); if (angleToCenter < Pi && angleToCenter > Pi / 4) { @@ -170,9 +167,7 @@ void Mouse::timerEvent(QTimerEvent *) continue; QLineF lineToMouse(QPointF(0, 0), mapFromItem(item, 0, 0)); - qreal angleToMouse = ::acos(lineToMouse.dx() / lineToMouse.length()); - if (lineToMouse.dy() < 0) - angleToMouse = TwoPi - angleToMouse; + qreal angleToMouse = std::atan2(lineToMouse.dy(), lineToMouse.dx()); angleToMouse = normalizeAngle((Pi - angleToMouse) + Pi / 2); if (angleToMouse >= 0 && angleToMouse < Pi / 2) { |