font-Roboto/scripts/lib/fontbuild/generateGlyph.py

# Copyright 2015 Google Inc. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.


import re
from string import find

from anchors import alignComponentsToAnchors, getAnchorByName


def parseComposite(composite):
    c = composite.split("=")
    d = c[1].split("/")
    glyphName = d[0]
    if len(d) == 1:
        offset = [0, 0]
    else:
        offset = [int(i) for i in d[1].split(",")]
    accentString = c[0]
    accents = accentString.split("+")
    baseName = accents.pop(0)
    accentNames = [i.split(":") for i in accents]
    return (glyphName, baseName, accentNames, offset)


def copyMarkAnchors(f, g, srcname, width):
    unicode_range = set(
        range(0x0030, 0x02B0) + range(0x1E00, 0x1EFF) +
        [0x430, 0x435, 0x440, 0x441, 0x445, 0x455, 0x456, 0x471])

    for anchor in f[srcname].anchors:
        if anchor.name in ("top_dd", "bottom_dd", "top0315"):
            g.appendAnchor(anchor.name, (anchor.x + width, anchor.y))

        if ("top" == anchor.name and
                (g.unicode in unicode_range or
                 g.name.endswith((".ccmp", ".smcp", ".NAV"))) and
                not any(a.name == "parent_top" for a in g.anchors)):
            g.appendAnchor("parent_top", anchor.position)

        if ("bottom" == anchor.name and
                (g.unicode in unicode_range or g.name.endswith(".smcp")) and
                not any(a.name == "bottom" for a in g.anchors)):
            g.appendAnchor("bottom", anchor.position)

    if any(a.name == "top" for a in g.anchors):
        return

    anchor_parent_top = getAnchorByName(g, "parent_top")
    if anchor_parent_top is not None:
        g.appendAnchor("top", anchor_parent_top.position)


def generateGlyph(f,gname,glyphList={}):
    glyphName, baseName, accentNames, offset = parseComposite(gname)

    if baseName.find("_") != -1:
        g = f.newGlyph(glyphName)
        for componentName in baseName.split("_"):
            g.appendComponent(componentName, (g.width, 0))
            g.width += f[componentName].width
            setUnicodeValue(g, glyphList)

    else:
        if f.has_key(glyphName):
            print('Existing glyph "%s" found in font, ignoring composition '
                  'rule "%s"' % (glyphName, gname))
            return
        try:
            f.compileGlyph(glyphName, baseName, accentNames)
        except KeyError as e:
            print('KeyError raised for composition rule "%s", likely "%s" '
                  'anchor not found in glyph "%s"' % (gname, e, baseName))
            return
        g = f[glyphName]
        setUnicodeValue(g, glyphList)
        copyMarkAnchors(f, g, baseName, offset[1] + offset[0])
        if len(accentNames) > 0:
            alignComponentsToAnchors(f, glyphName, baseName, accentNames)
        if offset[0] != 0 or offset[1] != 0:
            g.width += offset[1] + offset[0]
            g.move((offset[0], 0), anchors=False)


def setUnicodeValue(glyph, glyphList):
    """Try to ensure glyph has a unicode value -- used by FDK to make OTFs."""

    if glyph.name in glyphList:
        glyph.unicode = int(glyphList[glyph.name], 16)
    else:
        uvNameMatch = re.match("uni([\dA-F]{4})$", glyph.name)
        if uvNameMatch:
            glyph.unicode = int(uvNameMatch.group(1), 16)