2017-07-20 10:30 GMT+02:00 Patrick Stinson <patrickk...@gmail.com>: > Also it should be between two arbitrary points, so the sine wave may go from > top-right to bottom left, for example.
Right, but that's just a transformation of the bezier control points once you have them. Elvis > > On Jul 20, 2017, at 1:28 AM, Elvis Stansvik <elvst...@gmail.com> wrote: > > 2017-07-20 10:23 GMT+02:00 Jean-Michaël Celerier > <jeanmichael.celer...@gmail.com>: > > You can just compute the sine directly : > > for(int i = 0; i < width; i++) > { > int x = i; > int y = height / 2 + amplitude * std::sin(2 * M_PI * freq * i / width + > phase); > path.lineTo(x, y); > } > > > I think he wanted to avoid an approximation with straight lines and > use cubic beziers. > > Jean-Michaël: There seems to be many pages explaining the theory > behind sine approximation using Beziers if you Google. > > Elvis > > > > > > > ------- > Jean-Michaël Celerier > http://www.jcelerier.name > > On Thu, Jul 20, 2017 at 9:47 AM, Patrick Stinson <patrickk...@gmail.com> > wrote: > > > Hello! I want to figure out how to draw a sin wave between two QPointF’s > using QPainterPath. Calculating the cubic control points seems like the best > way, but I am far from mastering that theory. > > This is a diagramming app and the goal is to get a squiggly line between > two objects. > > Thanks! > _______________________________________________ > Interest mailing list > Interest@qt-project.org > http://lists.qt-project.org/mailman/listinfo/interest > > > > _______________________________________________ > Interest mailing list > Interest@qt-project.org > http://lists.qt-project.org/mailman/listinfo/interest > > _______________________________________________ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest