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Diffstat (limited to '.venv/lib/python3.12/site-packages/PIL/PcfFontFile.py')
| -rw-r--r-- | .venv/lib/python3.12/site-packages/PIL/PcfFontFile.py | 254 |
1 files changed, 254 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/PIL/PcfFontFile.py b/.venv/lib/python3.12/site-packages/PIL/PcfFontFile.py new file mode 100644 index 00000000..0d1968b1 --- /dev/null +++ b/.venv/lib/python3.12/site-packages/PIL/PcfFontFile.py @@ -0,0 +1,254 @@ +# +# THIS IS WORK IN PROGRESS +# +# The Python Imaging Library +# $Id$ +# +# portable compiled font file parser +# +# history: +# 1997-08-19 fl created +# 2003-09-13 fl fixed loading of unicode fonts +# +# Copyright (c) 1997-2003 by Secret Labs AB. +# Copyright (c) 1997-2003 by Fredrik Lundh. +# +# See the README file for information on usage and redistribution. +# +from __future__ import annotations + +import io +from typing import BinaryIO, Callable + +from . import FontFile, Image +from ._binary import i8 +from ._binary import i16be as b16 +from ._binary import i16le as l16 +from ._binary import i32be as b32 +from ._binary import i32le as l32 + +# -------------------------------------------------------------------- +# declarations + +PCF_MAGIC = 0x70636601 # "\x01fcp" + +PCF_PROPERTIES = 1 << 0 +PCF_ACCELERATORS = 1 << 1 +PCF_METRICS = 1 << 2 +PCF_BITMAPS = 1 << 3 +PCF_INK_METRICS = 1 << 4 +PCF_BDF_ENCODINGS = 1 << 5 +PCF_SWIDTHS = 1 << 6 +PCF_GLYPH_NAMES = 1 << 7 +PCF_BDF_ACCELERATORS = 1 << 8 + +BYTES_PER_ROW: list[Callable[[int], int]] = [ + lambda bits: ((bits + 7) >> 3), + lambda bits: ((bits + 15) >> 3) & ~1, + lambda bits: ((bits + 31) >> 3) & ~3, + lambda bits: ((bits + 63) >> 3) & ~7, +] + + +def sz(s: bytes, o: int) -> bytes: + return s[o : s.index(b"\0", o)] + + +class PcfFontFile(FontFile.FontFile): + """Font file plugin for the X11 PCF format.""" + + name = "name" + + def __init__(self, fp: BinaryIO, charset_encoding: str = "iso8859-1"): + self.charset_encoding = charset_encoding + + magic = l32(fp.read(4)) + if magic != PCF_MAGIC: + msg = "not a PCF file" + raise SyntaxError(msg) + + super().__init__() + + count = l32(fp.read(4)) + self.toc = {} + for i in range(count): + type = l32(fp.read(4)) + self.toc[type] = l32(fp.read(4)), l32(fp.read(4)), l32(fp.read(4)) + + self.fp = fp + + self.info = self._load_properties() + + metrics = self._load_metrics() + bitmaps = self._load_bitmaps(metrics) + encoding = self._load_encoding() + + # + # create glyph structure + + for ch, ix in enumerate(encoding): + if ix is not None: + ( + xsize, + ysize, + left, + right, + width, + ascent, + descent, + attributes, + ) = metrics[ix] + self.glyph[ch] = ( + (width, 0), + (left, descent - ysize, xsize + left, descent), + (0, 0, xsize, ysize), + bitmaps[ix], + ) + + def _getformat( + self, tag: int + ) -> tuple[BinaryIO, int, Callable[[bytes], int], Callable[[bytes], int]]: + format, size, offset = self.toc[tag] + + fp = self.fp + fp.seek(offset) + + format = l32(fp.read(4)) + + if format & 4: + i16, i32 = b16, b32 + else: + i16, i32 = l16, l32 + + return fp, format, i16, i32 + + def _load_properties(self) -> dict[bytes, bytes | int]: + # + # font properties + + properties = {} + + fp, format, i16, i32 = self._getformat(PCF_PROPERTIES) + + nprops = i32(fp.read(4)) + + # read property description + p = [(i32(fp.read(4)), i8(fp.read(1)), i32(fp.read(4))) for _ in range(nprops)] + + if nprops & 3: + fp.seek(4 - (nprops & 3), io.SEEK_CUR) # pad + + data = fp.read(i32(fp.read(4))) + + for k, s, v in p: + property_value: bytes | int = sz(data, v) if s else v + properties[sz(data, k)] = property_value + + return properties + + def _load_metrics(self) -> list[tuple[int, int, int, int, int, int, int, int]]: + # + # font metrics + + metrics: list[tuple[int, int, int, int, int, int, int, int]] = [] + + fp, format, i16, i32 = self._getformat(PCF_METRICS) + + append = metrics.append + + if (format & 0xFF00) == 0x100: + # "compressed" metrics + for i in range(i16(fp.read(2))): + left = i8(fp.read(1)) - 128 + right = i8(fp.read(1)) - 128 + width = i8(fp.read(1)) - 128 + ascent = i8(fp.read(1)) - 128 + descent = i8(fp.read(1)) - 128 + xsize = right - left + ysize = ascent + descent + append((xsize, ysize, left, right, width, ascent, descent, 0)) + + else: + # "jumbo" metrics + for i in range(i32(fp.read(4))): + left = i16(fp.read(2)) + right = i16(fp.read(2)) + width = i16(fp.read(2)) + ascent = i16(fp.read(2)) + descent = i16(fp.read(2)) + attributes = i16(fp.read(2)) + xsize = right - left + ysize = ascent + descent + append((xsize, ysize, left, right, width, ascent, descent, attributes)) + + return metrics + + def _load_bitmaps( + self, metrics: list[tuple[int, int, int, int, int, int, int, int]] + ) -> list[Image.Image]: + # + # bitmap data + + fp, format, i16, i32 = self._getformat(PCF_BITMAPS) + + nbitmaps = i32(fp.read(4)) + + if nbitmaps != len(metrics): + msg = "Wrong number of bitmaps" + raise OSError(msg) + + offsets = [i32(fp.read(4)) for _ in range(nbitmaps)] + + bitmap_sizes = [i32(fp.read(4)) for _ in range(4)] + + # byteorder = format & 4 # non-zero => MSB + bitorder = format & 8 # non-zero => MSB + padindex = format & 3 + + bitmapsize = bitmap_sizes[padindex] + offsets.append(bitmapsize) + + data = fp.read(bitmapsize) + + pad = BYTES_PER_ROW[padindex] + mode = "1;R" + if bitorder: + mode = "1" + + bitmaps = [] + for i in range(nbitmaps): + xsize, ysize = metrics[i][:2] + b, e = offsets[i : i + 2] + bitmaps.append( + Image.frombytes("1", (xsize, ysize), data[b:e], "raw", mode, pad(xsize)) + ) + + return bitmaps + + def _load_encoding(self) -> list[int | None]: + fp, format, i16, i32 = self._getformat(PCF_BDF_ENCODINGS) + + first_col, last_col = i16(fp.read(2)), i16(fp.read(2)) + first_row, last_row = i16(fp.read(2)), i16(fp.read(2)) + + i16(fp.read(2)) # default + + nencoding = (last_col - first_col + 1) * (last_row - first_row + 1) + + # map character code to bitmap index + encoding: list[int | None] = [None] * min(256, nencoding) + + encoding_offsets = [i16(fp.read(2)) for _ in range(nencoding)] + + for i in range(first_col, len(encoding)): + try: + encoding_offset = encoding_offsets[ + ord(bytearray([i]).decode(self.charset_encoding)) + ] + if encoding_offset != 0xFFFF: + encoding[i] = encoding_offset + except UnicodeDecodeError: + # character is not supported in selected encoding + pass + + return encoding |