diff options
Diffstat (limited to 'examples/widgets/graphicsview/collidingmice/mouse.cpp')
| -rw-r--r-- | examples/widgets/graphicsview/collidingmice/mouse.cpp | 10 |
1 files changed, 3 insertions, 7 deletions
diff --git a/examples/widgets/graphicsview/collidingmice/mouse.cpp b/examples/widgets/graphicsview/collidingmice/mouse.cpp index b94c650c18..cc1a15cd82 100644 --- a/examples/widgets/graphicsview/collidingmice/mouse.cpp +++ b/examples/widgets/graphicsview/collidingmice/mouse.cpp @@ -54,7 +54,7 @@ #include <QPainter> #include <QStyleOption> -#include <math.h> +#include <cmath> static const double Pi = 3.14159265358979323846264338327950288419717; static double TwoPi = 2.0 * Pi; @@ -140,9 +140,7 @@ void Mouse::advance(int step) //! [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) { @@ -171,9 +169,7 @@ void Mouse::advance(int step) 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) { |