Best way to remove glyph from RFont?

StephenNixon

Actually, hmm. I'm finding that the script in the docs for removing-glyphs-from-kerning doesn't seem to be removing kern pairs.

For example, this is failing to remove data around the a kerning:

font = CurrentFont()

# the glyph to be removed
glyphName = 'a'

# iterate over all kerning pairs in the font
for kerningPair in font.kerning.keys():

    # if the glyph is in the kerning pair:
    if glyphName in kerningPair:

        # remove the kerning pair
        print('removing kerning pair (%s, %s)...' % kerningPair)
        del font.kerning[kerningPair]

Even after running that, I still have all of the kern1 and kern2 data from a in the UFO.

StephenNixon

@frederik

also remove them from font.glyphOrder

Strangely, my script is able to remove most of the glyphs I ask it to, but it misses a few in glyphOrder. Can you see what I'm doing wrong here?

(The script below removes all lowercase glyphs in a font, but misses b d h n p r u v w lslash)

f = CurrentFont()

# copy space-separated glyph names here
glyphsToRemove = "a agrave aacute acircumflex atilde adieresis aring amacron abreve aogonek b c ccedilla cacute ccircumflex cdotaccent ccaron d dcaron e egrave eacute ecircumflex edieresis emacron ebreve edotaccent eogonek ecaron f g gcircumflex gbreve gdotaccent gcommaaccent h hcircumflex i igrave iacute icircumflex idieresis itilde imacron ibreve iogonek j jcircumflex k kcommaaccent l lacute lcommaaccent lcaron m n ntilde nacute ncommaaccent ncaron o ograve oacute ocircumflex otilde odieresis omacron obreve ohungarumlaut p q r racute rcommaaccent rcaron s sacute scircumflex scedilla scaron scommaaccent t tcommaaccent tcaron u ugrave uacute ucircumflex udieresis utilde umacron ubreve uring uhungarumlaut uogonek v w wcircumflex wgrave wacute wdieresis x y yacute ydieresis ycircumflex ygrave z zacute zdotaccent zcaron ae eth oslash thorn dcroat hbar ij ldot lslash eng oe tbar"

# clean up the rest of the data
for glyphToRemove in glyphsToRemove.split(" "):

    # remove from keys
    if glyphToRemove in f.keys():
        del f[glyphToRemove]

    # remove from glyphOrder 
    for glyphName in f.glyphOrder:
        if glyphName == glyphToRemove:
            del f.glyphOrder[glyphName]

    # GROUPS ------------------------------------------------------------

    # iterate over all groups in the font
    for groupName in f.groups.keys():

        # get the group
        group = f.groups[groupName]
        groupList = list(f.groups[groupName])

        # if glyph is in the group, remove it
        if glyphToRemove in group:
            print('removing %s from group %s...' % (glyphToRemove, groupName))
            groupList.remove(glyphToRemove)
            f.groups[groupName] = tuple(groupList)

    # KERNING -----------------------------------------------------------

    # iterate over all kerning pairs in the font
    for kerningPair in f.kerning.keys():

        # if glyph is in the kerning pair, remove it
        if glyphToRemove in kerningPair:
            print('removing kerning pair (%s, %s)...' % kerningPair)
            del f.kerning[kerningPair]

    # COMPONENTS --------------------------------------------------------

    # iterate over all glyphs in the font
    for glyph in f:

        # skip glyphs which don’t have components
        if not glyph.components:
            continue

        # iterate over all components in glyph
        for component in glyph.components:

            # if the base glyph is the glyph to be removed
            if component.baseGlyph == glyphToRemove:
                # delete the component
                glyph.removeComponent(component)

StephenNixon

@frederik Awesome, thanks!

gferreira

@StephenNixon ✔︎ docs updated. thanks for your comments!

frederik

You should also remove them from font.glyphOrder RoboFont builds up the template (placeholder) glyphs from a given glyph order.

StephenNixon

Actually, I'm finding that the glyph "placeholders" still hang around after I've gone through the steps in the docs to remove them from font, groups, kerning, and components.

Where do these glyphs come from, and how can I properly remove them?

StephenNixon

I found that the the "remove from groups" script listed on the "Adding and Removing glyphs" page didn't quite work, because you cannot directly remove an item from a tuple, and groups are tuples.

Instead, I needed to first convert the group tuple to a list, remove the glyph, and convert back to a tuple.

# iterate over all groups in the font
    for groupName in f.groups.keys():

        # get the group
        group = f.groups[groupName]
        groupList = list(f.groups[groupName])

        # if glyph is in the group, remove it
        if glyphName in group:
            print('removing %s from group %s...' % (glyphName, groupName))
            groupList.remove(glyphName)
            f.groups[groupName] = tuple(groupList)

Please correct me if I'm wrong about this, but it was erroring for me earlier, and seems to work well now.

It would also be worth updating that piece of the docs to reflect Frederick's latest comment about del font[glyphName].

frederik

small note: removeGlyph is deprecated use: del font["a"]

This does not remove the glyph from kerning or groups. The UFO spec allows to have group and kerning without having the glyph available in the UFO.

gferreira

and here’s how to remove all components of a given glyph:

font = CurrentFont()

glyphName = 'a'

for glyph in font:
    if not glyph.components:
        continue
    for component in glyph.components:
        if component.baseGlyph == glyphName:
            glyph.removeComponent(component)
            glyph.markColor = 1, 0, 0, 0.3

gferreira

the glyph can appear in the OpenType features code too – that’s a bit harder to solve with a script. simply removing it can break isometry between substitution classes, and the features will not compile.

SOLVED Best way to remove glyph from RFont?