nvgArc and nvgArcTo parameters correspondence and conversion

[GPrimola]

Hi,

I'm having a hard time to find resources on how to map this parameters of an elliptical arc:

• (x0 y0 rx ry xar laf sf x1 y1), where:

  • x0, y0 are the absolute coordinates of the initial point of the arc.

  • rx, ry are the radii of the ellipse (also known as its semi-major and semi-minor axes);

  • xar is the angle from the x-axis of the current coordinate system to the x-axis of the ellipse;

  • laf is the large arc flag, and is 0 if an arc spanning less than or equal to 180 degrees is chosen, or 1 if an arc spanning greater than 180 degrees is chosen;

  • sf is the sweep flag, and is 0 if the line joining center to arc sweeps through decreasing angles, or 1 if it sweeps through increasing angles.

  • x1, y1 are the absolute coordinates of the final point of the arc.

so they can fit to nvgArcTo and nvgArc functions to draw an elliptical arc.
I hope someone could help me with that.

Thank you!