Y up or down ?

[nyue]

I have the following code, depending on whether I concatenate the commands or call append separately, the Y direction is opposite, have my misunderstood the API ?

import drawSvg as draw

d = draw.Drawing(400, 400, origin='center', displayInline=False)

p1 = draw.Path(stroke='green', stroke_width=2, fill='transparent')
separate = False
if separate:
    p1.append('m', 31.75, 42.244047)
    p1.append('c', 0, 0, 68.055716, 12.241243, 97.51786, 35.529762)
else:
    p1.m(31.75, 42.244047).c(0, 0, 68.055716, 12.241243, 97.51786, 35.529762)
d.append(p1)

d.saveSvg('myspline.svg')
d.savePng('myspline.png')

[cduck]

drawSvg uses an upward pointing y-axis (see #11). You should use the named methods Path.m(), Path.c(), etc. Path.append() is a lower-level API that you should avoid.

[nyue]

If I am programmatically reading in data, what is a good way to provide data via the drawSVG API to Path object ?

I won't know in advanced how many pieces of information.

I was looking at calling append() since I am iterating through a set of data.

Cheers

[cduck]

OK. You can use something like getattr(mypath, 'm')(31.75, 42.244047) to indirectly call the method. The benefit of this is it will validate the data you pass (i.e. throw an error if you give the wrong number of arguments for a command).

[nyue]

Got it working. Both version looks the same now

import drawSvg as draw

def main(separate: bool):
    d = draw.Drawing(400, 400, origin='center', displayInline=False)

    p = draw.Path(stroke='green', stroke_width=2, fill='transparent')
    if separate:
        getattr(p,'m')(31.75, 42.244047)
        getattr(p,'c')(0, 0, 68.055716, 12.241243, 97.51786, 35.529762)
    else:
        p.m(31.75, 42.244047).c(0, 0, 68.055716, 12.241243, 97.51786, 35.529762)
    d.append(p)

    d.saveSvg('myspline_{}.svg'.format(separate))
    d.savePng('myspline_{}.png'.format(separate))

if __name__ == "__main__":
    # execute only if run as a script
    main(True)
    main(False)