mirror of
https://github.com/quantum5/win2xcur.git
synced 2025-08-04 00:58:53 -04:00
99 lines
3.8 KiB
Python
99 lines
3.8 KiB
Python
import struct
|
|
from collections import defaultdict
|
|
from typing import Any, Dict, List, Tuple, cast
|
|
|
|
from win2xcur.cursor import CursorFrame, CursorImage
|
|
from win2xcur.parser.base import BaseParser
|
|
from win2xcur.utils import image_from_pixels
|
|
|
|
|
|
class XCursorParser(BaseParser):
|
|
MAGIC = b'Xcur'
|
|
VERSION = 0x1_0000
|
|
FILE_HEADER = struct.Struct('<4sIII')
|
|
TOC_CHUNK = struct.Struct('<III')
|
|
CHUNK_IMAGE = 0xFFFD0002
|
|
IMAGE_HEADER = struct.Struct('<IIIIIIIII')
|
|
|
|
@classmethod
|
|
def can_parse(cls, blob: bytes) -> bool:
|
|
return blob[:len(cls.MAGIC)] == cls.MAGIC
|
|
|
|
def __init__(self, blob: bytes) -> None:
|
|
super().__init__(blob)
|
|
self.frames = self._parse()
|
|
|
|
def _unpack(self, struct_cls: struct.Struct, offset: int) -> Tuple[Any, ...]:
|
|
return struct_cls.unpack(self.blob[offset:offset + struct_cls.size])
|
|
|
|
def _parse(self) -> List[CursorFrame]:
|
|
magic, header_size, version, toc_size = self._unpack(self.FILE_HEADER, 0)
|
|
assert magic == self.MAGIC
|
|
|
|
if version != self.VERSION:
|
|
raise ValueError('Unsupported Xcursor version %r' % version)
|
|
|
|
offset = self.FILE_HEADER.size
|
|
chunks: List[Tuple[int, int, int]] = []
|
|
for i in range(toc_size):
|
|
chunk_type, chunk_subtype, position = self._unpack(self.TOC_CHUNK, offset)
|
|
chunks.append((chunk_type, chunk_subtype, position))
|
|
offset += self.TOC_CHUNK.size
|
|
|
|
images_by_size: Dict[int, List[Tuple[CursorImage, int]]] = defaultdict(list)
|
|
|
|
for chunk_type, chunk_subtype, position in chunks:
|
|
if chunk_type != self.CHUNK_IMAGE:
|
|
continue
|
|
|
|
size, actual_type, nominal_size, version, width, height, x_offset, y_offset, delay = \
|
|
self._unpack(self.IMAGE_HEADER, position)
|
|
|
|
if size != self.IMAGE_HEADER.size:
|
|
raise ValueError('Unexpected size: %r, expected %r' % (size, self.IMAGE_HEADER.size))
|
|
|
|
if actual_type != chunk_type:
|
|
raise ValueError('Unexpected chunk type: %r, expected %r' % (actual_type, chunk_type))
|
|
|
|
if nominal_size != chunk_subtype:
|
|
raise ValueError('Unexpected nominal size: %r, expected %r' % (nominal_size, chunk_subtype))
|
|
|
|
if width > 0x7FFF:
|
|
raise ValueError('Image width too large: %r' % width)
|
|
|
|
if height > 0x7FFF:
|
|
raise ValueError('Image height too large: %r' % height)
|
|
|
|
if x_offset > width:
|
|
raise ValueError('Hotspot x-coordinate too large: %r' % x_offset)
|
|
|
|
if y_offset > height:
|
|
raise ValueError('Hotspot x-coordinate too large: %r' % y_offset)
|
|
|
|
image_start = position + self.IMAGE_HEADER.size
|
|
image_size = width * height * 4
|
|
blob = self.blob[image_start:image_start + image_size]
|
|
if len(blob) != image_size:
|
|
raise ValueError('Invalid image at %d: expected %d bytes, got %d bytes' %
|
|
(image_size, image_size, len(blob)))
|
|
|
|
images_by_size[nominal_size].append(
|
|
(CursorImage(image_from_pixels(blob, width, height, 'ARGB', 'char'), (x_offset, y_offset)), delay)
|
|
)
|
|
|
|
if len(set(map(len, images_by_size.values()))) != 1:
|
|
raise ValueError('win2xcur does not support animations where each size has different number of frames')
|
|
|
|
result = []
|
|
for sequence in cast(Any, zip(*images_by_size.values())):
|
|
images: Tuple[CursorImage, ...]
|
|
delays: Tuple[int, ...]
|
|
images, delays = cast(Any, zip(*sequence))
|
|
|
|
if len(set(delays)) != 1:
|
|
raise ValueError('win2xcur does not support animations where each size has a different frame delay')
|
|
|
|
result.append(CursorFrame(list(images), delays[0]))
|
|
|
|
return result
|