Save control point information on LTCurve

[axelskyttner]

Feature request
Save control point information on bezier curves during parsing (as suggested by @jsvine in #530 (comment)).

Description
I need to render bezier curves in pdfs with different levels of resolutions and what jsvine suggests in PR-comment would solve my problem.

(Relatedly: Are the maintainers open to adding a .path attribute (which would contain the full path-command information that .paint_path is using) to LTCurve objects? That would allow users to reproduce the Beziér curves themselves — currently not possible because the command types themselves (m/l/h/c/v/y) are not accessible through .pts. If that sounds like a good idea, I can submit a separate PR once this one is resolved.)

Since I could not find any discussion regarding jsvine's suggestion I made this issue. Maybe there already exists an issue for this?

Example of use case

Example, this file contains a simple circle. Using a function like cubic_bezier below, I would like to be able to render points on the circle. Moreover, I need to be able to generate the points with different levels of resolution (e.g.res=5, res=10 and res=100) so the original control points needs to be saved on the curve object somehow.

def cubic_bezier(p0, p1, p2, p3, res=10):
    pts = []
    for i in range(0, res):
        t = i / res
        pt = pow(1-t, 3) * p0 + 3 * pow((1-t), 2)*t*p1 + 3 * (1-t) * pow(t,2)* p2 + pow(t, 3) * p3 
        pts.append(pt)
    return pts

Image of rendered points from bezier curve in pdf file

[JulianFeinauer]

I need this feature too. Is someone working on it? Otherwise i can also offer to work on a PR?

[pietermarsman]

@JulianFeinauer PR is more than welcome here!