splitTextToSize uses inverse scale factor

[zornwal]

The documentation of splitTextToSize states it uses "measurement units declared as default for the jsPDF instance".
Thus when I define the constructor

let doc = new jsPDF('p', 'px', 'a4');

a line that spans the entire page should be 595.28pt * 96 / 72 = ~793.7 pixels wide.
One would then expect that

let splitText = doc.splitTextToSize(longText, 793.7);
doc.text(splitText, 0, 0)

produces lines that spans the entire page, but this not the case.

A page-spanning line is achieved at ~446 pixels like so

let splitText = doc.splitTextToSize(longText, 446);
doc.text(splitText, 0, 0)

Now, 446 happens to be 595.28 / (96 / 72), or 595.28 * (72/96), leading me to conclude that, somehow, an inverse scale factor is being applied between pt and px when adding text

[HackbrettXXX]

The 'px' scaling factor is wrong per default. Try enabling the px_scaling hotfix and see if this gives the expected result.

[zornwal]

Okay, well I've made it work by preemptively dividing with the scale factor, so that they cancel out and give the correct result. Not too pretty, but I'd rather not redo all my pixel calculations 😁

[HackbrettXXX]

Alright, so this issue can be closed?

[zornwal]

If it's a known issue on your end, feel free to close it, I suggest referencing the hotfixes README from the main README though 😄 it's not very clear that there are hotfixes that can be applied.

[HackbrettXXX]

It's documented in the jsPDF constructor API doc: http://raw.githack.com/MrRio/jsPDF/master/docs/jsPDF.html, but yeah, mentioning it in the readme as well is probably a good idea.