Units used in bold, thin and hollow transformations

FontCreator - Font Editor FontCreator - Support
1

Hello. Nowadays I am occasionally finding the need to use the thin/bold transformations via the Glyph Transformer wizard. It is absolutely unclear however as to what the numbers I am entering into the horizontal/vertical fields signify. Do they signify percentage of change, or do they signify absolute funit values, or what? Neither the interface nor the documentation clarifies this. Can anyone please throw light?

Previously I had posted http://forum.high-logic.com:9080/t/scaling-a-glyph-while-maintaining-stroke-width/3381/1 which is also related, but I still am not clear as to what these parameters are, which is why I am asking.

2

Unless otherwise shown on the transform dialogue, then the units are always funits. If you use the Effects, Italic transformation, or the rotate transformation, then the dialogue shows that the units are in degrees and decimals of a degree.
Transform Angle.png
If you use the scale transformation, the scale is in percentages.
Transform Percent.png

3

Hmm, only experimentation reveals that the funits are doubled in the sense that if I ask FC to thin a glyph vertically by 10 funits, a vertical stroke width of 100 is actually reduced to 100 - 2 * 10 = 80, and likewise horizontally.

So if w0 is the current width and w1 is the desired (smaller) width, then we should ask the wizard to thin the glyph horizontally by (w0-w1)/2. Likewise for height, do it vertically.

Conversely for boldening, if w0 is the current width and w1 is the desired (higher) width, the value is (w1-w0)/2. Likewise for height.

BTW can’t these bold/thin transforms be unified into a single transform, with negative parameters meaning thinning and positive (default) means boldening?

And what is the reason for Glyph Transform not being undoable, which seems somewhat silly (sorry to say)?

4

The amount of memory required to store the undo information can be way too big.

5

See all you need to store is the initial state and the final state. I don’t think it is important to store each individual transform. So maybe if the number of glyphs operated upon is less than a certain number (say 10) then you can save it in the undo buffer. Otherwise you can throw the usual warning (reword it to “Transforms for more than ten glyphs cannot be undone”) and do it as it is done now. Would this be possible?

6

It was a design decision to not allow undo there. It requires a lot of development efforts to implement it. I can add your request to our to-do list, but I believe there are more important things on it.

7

To work around the undo problem, copy the selected glyphs to the clipboard, then perform the transformation. Paste the glyphs back immediately, then undo the paste operation. Now, if you want to try with different transformation parameters, you can undo and try again.

8

Hm? Undo is already there, no? Would it really be more complicated than:

if len(selected_glyphs) > 10:
    msgbox(opt.warning, "Operations on more than 10 glyphs cannot be undone.")
    undobuffer.empty()

Well I leave it to you.

Yes bhante, you had mentioned this in your tutorial on glyph transformer. I just would like to avoid the trouble. Anyhow…

9

I’m a little puzzled why the Validation wizard can be set to detect and fix errors and be undoable, but a glyph transform isn’t.

If you can undo changes to a lot of characters a 50,000 glyph font (like Arial Unicode) after the Validation wizard runs, why can’t you undo a glyph transformation to even a single glyph? If you are worried about multiple glyph transforms eating up memory, then limiting to the last one on undo would be fine for 99% of use cases.

Also, FontCreator needs to be rebuilt for 64-bit, since you can’t even buy a 32-bit Windows OS any more. That, plus memory at $5/GB means that memory shouldn’t be an issue.

10

Fair enough, we have added this enhancement to the to-do list, but don’t expect it for the next couple of months.

We intend to release a 64-bit version with the next upcoming major release.