Source code for fontTools.ttLib.tables.C_P_A_L_

# Copyright 2013 Google, Inc. All Rights Reserved.
#
# Google Author(s): Behdad Esfahbod

from fontTools.misc.textTools import bytesjoin, safeEval
from . import DefaultTable
import array
from collections import namedtuple
import struct
import sys


[docs] class table_C_P_A_L_(DefaultTable.DefaultTable): NO_NAME_ID = 0xFFFF DEFAULT_PALETTE_TYPE = 0 def __init__(self, tag=None): DefaultTable.DefaultTable.__init__(self, tag) self.palettes = [] self.paletteTypes = [] self.paletteLabels = [] self.paletteEntryLabels = []
[docs] def decompile(self, data, ttFont): ( self.version, self.numPaletteEntries, numPalettes, numColorRecords, goffsetFirstColorRecord, ) = struct.unpack(">HHHHL", data[:12]) assert ( self.version <= 1 ), "Version of CPAL table is higher than I know how to handle" self.palettes = [] pos = 12 for i in range(numPalettes): startIndex = struct.unpack(">H", data[pos : pos + 2])[0] assert startIndex + self.numPaletteEntries <= numColorRecords pos += 2 palette = [] ppos = goffsetFirstColorRecord + startIndex * 4 for j in range(self.numPaletteEntries): palette.append(Color(*struct.unpack(">BBBB", data[ppos : ppos + 4]))) ppos += 4 self.palettes.append(palette) if self.version == 0: offsetToPaletteTypeArray = 0 offsetToPaletteLabelArray = 0 offsetToPaletteEntryLabelArray = 0 else: pos = 12 + numPalettes * 2 ( offsetToPaletteTypeArray, offsetToPaletteLabelArray, offsetToPaletteEntryLabelArray, ) = struct.unpack(">LLL", data[pos : pos + 12]) self.paletteTypes = self._decompileUInt32Array( data, offsetToPaletteTypeArray, numPalettes, default=self.DEFAULT_PALETTE_TYPE, ) self.paletteLabels = self._decompileUInt16Array( data, offsetToPaletteLabelArray, numPalettes, default=self.NO_NAME_ID ) self.paletteEntryLabels = self._decompileUInt16Array( data, offsetToPaletteEntryLabelArray, self.numPaletteEntries, default=self.NO_NAME_ID, )
def _decompileUInt16Array(self, data, offset, numElements, default=0): if offset == 0: return [default] * numElements result = array.array("H", data[offset : offset + 2 * numElements]) if sys.byteorder != "big": result.byteswap() assert len(result) == numElements, result return result.tolist() def _decompileUInt32Array(self, data, offset, numElements, default=0): if offset == 0: return [default] * numElements result = array.array("I", data[offset : offset + 4 * numElements]) if sys.byteorder != "big": result.byteswap() assert len(result) == numElements, result return result.tolist()
[docs] def compile(self, ttFont): colorRecordIndices, colorRecords = self._compileColorRecords() paletteTypes = self._compilePaletteTypes() paletteLabels = self._compilePaletteLabels() paletteEntryLabels = self._compilePaletteEntryLabels() numColorRecords = len(colorRecords) // 4 offsetToFirstColorRecord = 12 + len(colorRecordIndices) if self.version >= 1: offsetToFirstColorRecord += 12 header = struct.pack( ">HHHHL", self.version, self.numPaletteEntries, len(self.palettes), numColorRecords, offsetToFirstColorRecord, ) if self.version == 0: dataList = [header, colorRecordIndices, colorRecords] else: pos = offsetToFirstColorRecord + len(colorRecords) if len(paletteTypes) == 0: offsetToPaletteTypeArray = 0 else: offsetToPaletteTypeArray = pos pos += len(paletteTypes) if len(paletteLabels) == 0: offsetToPaletteLabelArray = 0 else: offsetToPaletteLabelArray = pos pos += len(paletteLabels) if len(paletteEntryLabels) == 0: offsetToPaletteEntryLabelArray = 0 else: offsetToPaletteEntryLabelArray = pos pos += len(paletteLabels) header1 = struct.pack( ">LLL", offsetToPaletteTypeArray, offsetToPaletteLabelArray, offsetToPaletteEntryLabelArray, ) dataList = [ header, colorRecordIndices, header1, colorRecords, paletteTypes, paletteLabels, paletteEntryLabels, ] return bytesjoin(dataList)
def _compilePalette(self, palette): assert len(palette) == self.numPaletteEntries pack = lambda c: struct.pack(">BBBB", c.blue, c.green, c.red, c.alpha) return bytesjoin([pack(color) for color in palette]) def _compileColorRecords(self): colorRecords, colorRecordIndices, pool = [], [], {} for palette in self.palettes: packedPalette = self._compilePalette(palette) if packedPalette in pool: index = pool[packedPalette] else: index = len(colorRecords) colorRecords.append(packedPalette) pool[packedPalette] = index colorRecordIndices.append(struct.pack(">H", index * self.numPaletteEntries)) return bytesjoin(colorRecordIndices), bytesjoin(colorRecords) def _compilePaletteTypes(self): if self.version == 0 or not any(self.paletteTypes): return b"" assert len(self.paletteTypes) == len(self.palettes) result = bytesjoin([struct.pack(">I", ptype) for ptype in self.paletteTypes]) assert len(result) == 4 * len(self.palettes) return result def _compilePaletteLabels(self): if self.version == 0 or all(l == self.NO_NAME_ID for l in self.paletteLabels): return b"" assert len(self.paletteLabels) == len(self.palettes) result = bytesjoin([struct.pack(">H", label) for label in self.paletteLabels]) assert len(result) == 2 * len(self.palettes) return result def _compilePaletteEntryLabels(self): if self.version == 0 or all( l == self.NO_NAME_ID for l in self.paletteEntryLabels ): return b"" assert len(self.paletteEntryLabels) == self.numPaletteEntries result = bytesjoin( [struct.pack(">H", label) for label in self.paletteEntryLabels] ) assert len(result) == 2 * self.numPaletteEntries return result
[docs] def toXML(self, writer, ttFont): numPalettes = len(self.palettes) paletteLabels = {i: nameID for (i, nameID) in enumerate(self.paletteLabels)} paletteTypes = {i: typ for (i, typ) in enumerate(self.paletteTypes)} writer.simpletag("version", value=self.version) writer.newline() writer.simpletag("numPaletteEntries", value=self.numPaletteEntries) writer.newline() for index, palette in enumerate(self.palettes): attrs = {"index": index} paletteType = paletteTypes.get(index, self.DEFAULT_PALETTE_TYPE) paletteLabel = paletteLabels.get(index, self.NO_NAME_ID) if self.version > 0 and paletteLabel != self.NO_NAME_ID: attrs["label"] = paletteLabel if self.version > 0 and paletteType != self.DEFAULT_PALETTE_TYPE: attrs["type"] = paletteType writer.begintag("palette", **attrs) writer.newline() if ( self.version > 0 and paletteLabel != self.NO_NAME_ID and ttFont and "name" in ttFont ): name = ttFont["name"].getDebugName(paletteLabel) if name is not None: writer.comment(name) writer.newline() assert len(palette) == self.numPaletteEntries for cindex, color in enumerate(palette): color.toXML(writer, ttFont, cindex) writer.endtag("palette") writer.newline() if self.version > 0 and not all( l == self.NO_NAME_ID for l in self.paletteEntryLabels ): writer.begintag("paletteEntryLabels") writer.newline() for index, label in enumerate(self.paletteEntryLabels): if label != self.NO_NAME_ID: writer.simpletag("label", index=index, value=label) if self.version > 0 and label and ttFont and "name" in ttFont: name = ttFont["name"].getDebugName(label) if name is not None: writer.comment(name) writer.newline() writer.endtag("paletteEntryLabels") writer.newline()
[docs] def fromXML(self, name, attrs, content, ttFont): if name == "palette": self.paletteLabels.append(int(attrs.get("label", self.NO_NAME_ID))) self.paletteTypes.append(int(attrs.get("type", self.DEFAULT_PALETTE_TYPE))) palette = [] for element in content: if isinstance(element, str): continue attrs = element[1] color = Color.fromHex(attrs["value"]) palette.append(color) self.palettes.append(palette) elif name == "paletteEntryLabels": colorLabels = {} for element in content: if isinstance(element, str): continue elementName, elementAttr, _ = element if elementName == "label": labelIndex = safeEval(elementAttr["index"]) nameID = safeEval(elementAttr["value"]) colorLabels[labelIndex] = nameID self.paletteEntryLabels = [ colorLabels.get(i, self.NO_NAME_ID) for i in range(self.numPaletteEntries) ] elif "value" in attrs: value = safeEval(attrs["value"]) setattr(self, name, value) if name == "numPaletteEntries": self.paletteEntryLabels = [self.NO_NAME_ID] * self.numPaletteEntries
[docs] class Color(namedtuple("Color", "blue green red alpha")):
[docs] def hex(self): return "#%02X%02X%02X%02X" % (self.red, self.green, self.blue, self.alpha)
def __repr__(self): return self.hex()
[docs] def toXML(self, writer, ttFont, index=None): writer.simpletag("color", value=self.hex(), index=index) writer.newline()
[docs] @classmethod def fromHex(cls, value): if value[0] == "#": value = value[1:] red = int(value[0:2], 16) green = int(value[2:4], 16) blue = int(value[4:6], 16) alpha = int(value[6:8], 16) if len(value) >= 8 else 0xFF return cls(red=red, green=green, blue=blue, alpha=alpha)
[docs] @classmethod def fromRGBA(cls, red, green, blue, alpha): return cls(red=red, green=green, blue=blue, alpha=alpha)