diff options
Diffstat (limited to 'examples/widgets/graphicsview/elasticnodes/edge.cpp')
| -rw-r--r-- | examples/widgets/graphicsview/elasticnodes/edge.cpp | 28 |
1 files changed, 11 insertions, 17 deletions
diff --git a/examples/widgets/graphicsview/elasticnodes/edge.cpp b/examples/widgets/graphicsview/elasticnodes/edge.cpp index e794e803cf..aec12b4225 100644 --- a/examples/widgets/graphicsview/elasticnodes/edge.cpp +++ b/examples/widgets/graphicsview/elasticnodes/edge.cpp @@ -51,13 +51,9 @@ #include "edge.h" #include "node.h" -#include <math.h> - +#include <qmath.h> #include <QPainter> -static const double Pi = 3.14159265358979323846264338327950288419717; -static double TwoPi = 2.0 * Pi; - //! [0] Edge::Edge(Node *sourceNode, Node *destNode) : arrowSize(10) @@ -139,18 +135,16 @@ void Edge::paint(QPainter *painter, const QStyleOptionGraphicsItem *, QWidget *) //! [6] // Draw the arrows - double angle = ::acos(line.dx() / line.length()); - if (line.dy() >= 0) - angle = TwoPi - angle; - - QPointF sourceArrowP1 = sourcePoint + QPointF(sin(angle + Pi / 3) * arrowSize, - cos(angle + Pi / 3) * arrowSize); - QPointF sourceArrowP2 = sourcePoint + QPointF(sin(angle + Pi - Pi / 3) * arrowSize, - cos(angle + Pi - Pi / 3) * arrowSize); - QPointF destArrowP1 = destPoint + QPointF(sin(angle - Pi / 3) * arrowSize, - cos(angle - Pi / 3) * arrowSize); - QPointF destArrowP2 = destPoint + QPointF(sin(angle - Pi + Pi / 3) * arrowSize, - cos(angle - Pi + Pi / 3) * arrowSize); + double angle = std::atan2(-line.dy(), line.dx()); + + QPointF sourceArrowP1 = sourcePoint + QPointF(sin(angle + M_PI / 3) * arrowSize, + cos(angle + M_PI / 3) * arrowSize); + QPointF sourceArrowP2 = sourcePoint + QPointF(sin(angle + M_PI - M_PI / 3) * arrowSize, + cos(angle + M_PI - M_PI / 3) * arrowSize); + QPointF destArrowP1 = destPoint + QPointF(sin(angle - M_PI / 3) * arrowSize, + cos(angle - M_PI / 3) * arrowSize); + QPointF destArrowP2 = destPoint + QPointF(sin(angle - M_PI + M_PI / 3) * arrowSize, + cos(angle - M_PI + M_PI / 3) * arrowSize); painter->setBrush(Qt::black); painter->drawPolygon(QPolygonF() << line.p1() << sourceArrowP1 << sourceArrowP2); |