SVGArcApproximator::approximate() doesn't work properly about php-svg

[captain-igloo]

Great, good work :)

[meyfa]

You are right, the example you gave is indeed computed incorrectly. Investigating.

[meyfa]

I hope to have fixed it in 97ff139. At least your example works for me now, as did some others I tried. Could you perhaps verify this as well, using the newest commit?

[captain-igloo]

I have tried a few examples and it seems to be working now. Thanks.
A small thing - how about adding a test for $sweep = true. I see line 142 is not covered by your tests currently.
Also I asked before about fmod() line 131. Since vectorAngle2() returns a number between -pi and pi (?) the fmod shouldn't be needed.
Lastly vectorAngle2() will divide by zero if $vec1x and $vec1y are both zero or if $vec2x and $vec2y are both zero.

[meyfa]

I added tests for all 4 combinations of LargeArc and Sweep flags (c9c2244). Also, you are right about the fmod call not being needed, I have since removed it (89bc58e).

Moreover, I considered the division by zero in vectorAngle and vectorAngle2 and came to the conclusion that the formulas provided by W3C are made to prevent this from ever becoming an issue. Entering the formulas into a computer algebra system and solving for inputs that would yield a norm of 0 gave no results. So unless I mistyped something, it won't be a problem.

The only thing that remains, then, is to implement radius scaling in case the ellipse would be too small to cover the endpoints. The algorithm is described in the W3C document as well and I will work on it now.

[meyfa]

Radius scaling is done (0a26b4a). Unless you can come up with further defects in SVGArcApproximator, I am going to close this issue.