使用 C++ 在 Qt5 中显示曲线

Question

Now, I have geometry information of some curves, which are given with the following format.

<LineString><coordinates>-43.276042355627,-32.8022614460173,0.0 -43.9683944443137,-31.9135623685828,0.0 -44.4979806584518,-31.1926527722131,0.0</coordinates></LineString>

I would like to show them in my scene. I know I can do this by creating multiple QGraphicsLineItem s one by one. But is there any other easy way to do this, like one curve item?

Answer 1

You can use QGraphicsPathItem along with QPainterPath . Reimplement the QGraphicsPathItem , add a method that receives your original points. Create a QPainterPath and iterate over points. Use moveTo on the first point and lineTo for the next points. Then call setPath of QGraphicsPathItem to redraw the new curve.