right align does not work properly if there is a "W" or a parenthesis in the text

[bwl21]

Thank you for submitting an issue to jsPDF. Please read carefully.

Are you using the latest version of jsPDF?

using https://rawgit.com/MrRio/jsPDF/master/

Have you tried using jspdf.debug.js?

Steps to reproduce

Try with:

var doc = new jsPDF();

doc.text(10,10, "jspdf version " + jsPDF.version)

doc.setFont("helvetica");
doc.setFontType("bold");
doc.setFontSize(35)
doc.setFontStyle('bold')
doc.text(160,120, "aaaaa bbbbb cccc Wnnnnn\naaaa bbbb cccc nnnn", {align:'right'});
doc.text(160,150, "aaaaa bbbbb cccc wnnnnn\naaaa bbbb cccc nnnn", {align:'right'});
doc.text(160,180, "aaaaa bbbbb cccc wnnnnn\naaaa bbbb Wccc nnnn", {align:'right'});

doc.text(160, 40, ["...","III", "MMM", "M(M)M","M{i}M"],
{align:'right'})


doc.line(160, 0, 160, 190);

Ideally a link too. Try fork this http://jsbin.com/rilace/edit?html,js,output

What I saw

What I expected

In all cases the text lines should be right aligned properly.
But it is only the case if there is no "W".

[Uzlopak]

Without debugging I would guess that it is an issue of precision.

I guess, that the code for calculating the width is ok, but writing it to the PDF causes the issue.
We do two digit precision usually. Maybe if we patch it to three digit precision would fix it?

[bwl21]

The stuff with "W" might be tolerated, but with "(" ")" is really significant. I played around with getTextWidth but could not find an anomaly with "(" ...

I played around by adding more lines. The deviation with "W" is about 1 mm, with "M" about 0.5 mm. but with "(" ist is about 4mm.

[Uzlopak]

Pro Tip: Avoid paranthesis and the letters M and W

[Uzlopak]

[bwl21]

;-(

[Uzlopak]

I think, that this can be solved, if we replace all the f2 and f3 calls to a new generic function which rounds the numbers to a specific precision. Then we can set the overall precision e.g. to 3 or 4 decimal after the comma. This should result in the expected behaviour.

[bwl21]

But wit parenthesis it seems to be caused by something else, as the deviation is close to a character width.

[Uzlopak]

Hmm. Still, could be a rounding problem. Will take a look in few days.

[bwl21]

I dived a bit into the code and found, that somewhere ( in text is replaced by \(. The resulting string is used to compute the position in jspdf.debug.js line 13923

var getStringUnitWidth = API.getStringUnitWidth = function (text, options) {

I could not find a proper place to fix it ...