Hebrew kerning interacts badly with text anchors
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
Inkscape |
In Progress
|
Medium
|
David Mathog |
Bug Description
Most likely this applies to all R->L languages.
In the attached kerning example in English a variety of x,y kerns were applied. The left justified paragraph was constructed, and then the other ones were constructed from it by changing the text-anchor via the GUI (LJ ->CJ or RJ). All of these work as expected, so that the kerned lines still change justification properly. Both the SVG and a screen shot will be posted.
Not so for Hebrew. While Hebrew anchor works more or less properly, except for bug 1169348, it interacts terribly with kerning. The Hebrew kerning example is mostly like the English one, except the RJ version was constructed first. Mixing languages is another quagmire so the x,y kerning values were coded using Hebrew letters, see the table at bottom. With Hebrew changing the anchor RJ->LJ or CJ screws up the alignment badly whenever there is kerning present. IBoth the SVG and a screen shot will be posted.
If I had to guess what was going on it would be that the code involved is not taking into account the issue that dx for kerning "in the direction of the text" has the opposite sign for R->L languages.
Note that Inkscape is not alone in having Hebrew problems, Firefox for instance, inverts the order of the glyphs in the hebrew SVG examples.
Regarding the screen shot of the Hebrew kerning example...
The top row of text boxes include Hebrew text without kerning. The RJ one was constructed first, then the other two were made by changing the text anchor with the GUI (-> CJ or LJ). There is a very slight shift with respect to the bounding box, but overall this was the correct outcome.
The second row of text boxes was the same test as above, but with text which includes kerning. Changing the text-anchor results in the text not falling in the correct location with respect to the bounding box.