| from fontTools.misc import sstruct |
| from fontTools.misc.textTools import readHex, safeEval |
| import struct |
| |
| |
| sbixGlyphHeaderFormat = """ |
| > |
| originOffsetX: h # The x-value of the point in the glyph relative to its |
| # lower-left corner which corresponds to the origin of |
| # the glyph on the screen, that is the point on the |
| # baseline at the left edge of the glyph. |
| originOffsetY: h # The y-value of the point in the glyph relative to its |
| # lower-left corner which corresponds to the origin of |
| # the glyph on the screen, that is the point on the |
| # baseline at the left edge of the glyph. |
| graphicType: 4s # e.g. "png " |
| """ |
| |
| sbixGlyphHeaderFormatSize = sstruct.calcsize(sbixGlyphHeaderFormat) |
| |
| |
| class Glyph(object): |
| def __init__( |
| self, |
| glyphName=None, |
| referenceGlyphName=None, |
| originOffsetX=0, |
| originOffsetY=0, |
| graphicType=None, |
| imageData=None, |
| rawdata=None, |
| gid=0, |
| ): |
| self.gid = gid |
| self.glyphName = glyphName |
| self.referenceGlyphName = referenceGlyphName |
| self.originOffsetX = originOffsetX |
| self.originOffsetY = originOffsetY |
| self.rawdata = rawdata |
| self.graphicType = graphicType |
| self.imageData = imageData |
| |
| # fix self.graphicType if it is null terminated or too short |
| if self.graphicType is not None: |
| if self.graphicType[-1] == "\0": |
| self.graphicType = self.graphicType[:-1] |
| if len(self.graphicType) > 4: |
| from fontTools import ttLib |
| |
| raise ttLib.TTLibError( |
| "Glyph.graphicType must not be longer than 4 characters." |
| ) |
| elif len(self.graphicType) < 4: |
| # pad with spaces |
| self.graphicType += " "[: (4 - len(self.graphicType))] |
| |
| def is_reference_type(self): |
| """Returns True if this glyph is a reference to another glyph's image data.""" |
| return self.graphicType == "dupe" or self.graphicType == "flip" |
| |
| def decompile(self, ttFont): |
| self.glyphName = ttFont.getGlyphName(self.gid) |
| if self.rawdata is None: |
| from fontTools import ttLib |
| |
| raise ttLib.TTLibError("No table data to decompile") |
| if len(self.rawdata) > 0: |
| if len(self.rawdata) < sbixGlyphHeaderFormatSize: |
| from fontTools import ttLib |
| |
| # print "Glyph %i header too short: Expected %x, got %x." % (self.gid, sbixGlyphHeaderFormatSize, len(self.rawdata)) |
| raise ttLib.TTLibError("Glyph header too short.") |
| |
| sstruct.unpack( |
| sbixGlyphHeaderFormat, self.rawdata[:sbixGlyphHeaderFormatSize], self |
| ) |
| |
| if self.is_reference_type(): |
| # this glyph is a reference to another glyph's image data |
| (gid,) = struct.unpack(">H", self.rawdata[sbixGlyphHeaderFormatSize:]) |
| self.referenceGlyphName = ttFont.getGlyphName(gid) |
| else: |
| self.imageData = self.rawdata[sbixGlyphHeaderFormatSize:] |
| self.referenceGlyphName = None |
| # clean up |
| del self.rawdata |
| del self.gid |
| |
| def compile(self, ttFont): |
| if self.glyphName is None: |
| from fontTools import ttLib |
| |
| raise ttLib.TTLibError("Can't compile Glyph without glyph name") |
| # TODO: if ttFont has no maxp, cmap etc., ignore glyph names and compile by index? |
| # (needed if you just want to compile the sbix table on its own) |
| self.gid = struct.pack(">H", ttFont.getGlyphID(self.glyphName)) |
| if self.graphicType is None: |
| rawdata = b"" |
| else: |
| rawdata = sstruct.pack(sbixGlyphHeaderFormat, self) |
| if self.is_reference_type(): |
| rawdata += struct.pack(">H", ttFont.getGlyphID(self.referenceGlyphName)) |
| else: |
| assert self.imageData is not None |
| rawdata += self.imageData |
| self.rawdata = rawdata |
| |
| def toXML(self, xmlWriter, ttFont): |
| if self.graphicType is None: |
| # TODO: ignore empty glyphs? |
| # a glyph data entry is required for each glyph, |
| # but empty ones can be calculated at compile time |
| xmlWriter.simpletag("glyph", name=self.glyphName) |
| xmlWriter.newline() |
| return |
| xmlWriter.begintag( |
| "glyph", |
| graphicType=self.graphicType, |
| name=self.glyphName, |
| originOffsetX=self.originOffsetX, |
| originOffsetY=self.originOffsetY, |
| ) |
| xmlWriter.newline() |
| if self.is_reference_type(): |
| # this glyph is a reference to another glyph id. |
| xmlWriter.simpletag("ref", glyphname=self.referenceGlyphName) |
| else: |
| xmlWriter.begintag("hexdata") |
| xmlWriter.newline() |
| xmlWriter.dumphex(self.imageData) |
| xmlWriter.endtag("hexdata") |
| xmlWriter.newline() |
| xmlWriter.endtag("glyph") |
| xmlWriter.newline() |
| |
| def fromXML(self, name, attrs, content, ttFont): |
| if name == "ref": |
| # this glyph i.e. a reference to another glyph's image data. |
| # in this case imageData contains the glyph id of the reference glyph |
| # get glyph id from glyphname |
| glyphname = safeEval("'''" + attrs["glyphname"] + "'''") |
| self.imageData = struct.pack(">H", ttFont.getGlyphID(glyphname)) |
| self.referenceGlyphName = glyphname |
| elif name == "hexdata": |
| self.imageData = readHex(content) |
| else: |
| from fontTools import ttLib |
| |
| raise ttLib.TTLibError("can't handle '%s' element" % name) |