Draw Inscribed circles and ellipses

While the spline/text speed has improved substantially, more work is still needed on them, and a code review is undergoing.

Aside from the text insertion speed, there’s an independent long-term goal of adding C++11 support. We will do more than simply making it look like C++11, instead, performance, code readability and correctness of implementation should be among our goals.

Now, some new features implemented in the master branch. Please help testing them!

Several new drawing methods for ellipses/circles:

  • Ellipse inscribed in a convex quadrilateral, i.e., the ellipse tangential to four given lines;
  • Ellipse with given foci, a point on ellipse or the total distance to foci;
  • Ellipse with given center, three points on ellipse;
  • Ellipse with major axis in x-/y-directions with given center, and two points on ellipse;
  • Ellipse with major axis in x-/y-directions and four given points on ellipse;
  • Circle inscribed in a triangle, i.e., tangential to three given lines.

Please note the complexity of these new construction algorithms, so, we do expect bugs for certain drawing conditions.

If you find a bug in LibreCAD or you would like LibreCAD to do more, please file your report/request at our tracker on sourceforge:


The LibreCAD team

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