Initial Commit

Initial commit of Code Base.

addons/twitcher/media/native/gif-lzw/lsbbitunpacker.gd

@@ -0,0 +1,44 @@
+@tool
+extends RefCounted
+
+class LSBLZWBitUnpacker:
+	var chunk_stream: PackedByteArray
+	var bit_index: int = 0
+	var byte: int
+	var byte_index: int = 0
+
+	func _init(_chunk_stream: PackedByteArray):
+		chunk_stream = _chunk_stream
+		get_byte()
+
+	func get_bit(value: int, index: int) -> int:
+		return (value >> index) & 1
+
+	func set_bit(value: int, index: int) -> int:
+		return value | (1 << index)
+
+	func get_byte():
+		byte = chunk_stream[byte_index]
+		byte_index += 1
+		bit_index = 0
+
+	func read_bits(bits_count: int) -> int:
+		var result: int = 0
+		var result_bit_index: int = 0
+
+		for _i in range(bits_count):
+			if get_bit(byte, bit_index) == 1:
+				result = set_bit(result, result_bit_index)
+			result_bit_index += 1
+			bit_index += 1
+
+			if chunk_stream.size() == byte_index && result_bit_index == bits_count:
+				return result;
+
+			if bit_index == 8:
+				get_byte()
+
+		return result
+
+	func remove_bits(bits_count: int) -> void:
+		read_bits(bits_count)