bits 1.3.0

Write in bits instead of bytes for packing data tighter, and increasing headaches.

Write data in bits for more control over the data you write. This is useful for writing binary data.

Features

Bit Buffers

You can create a BitBuffer from / export to the following formats

• UInt8List
• ByteBuffer
• BytesBuilder
• ByteData
• Base64 Strings
• Compressed Base64 Strings (see threshold package)

Data Types

• Write VarUInts (8, 16, 32, 64)
  • 2 bits for the length of the VarUInt
  • 8-64 bits for the value
  • 10-70 bits total
• Write VarInts (8, 16, 32, 64)
  • 1 bit for the sign
  • 2 bits for the length of the VarInt
  • 8-64 bits for the value
  • 11-71 bits total
• Write VarDoubles (8, 16, 32, 64) with variable precision
  • 1 bit for the sign
  • 2 bits for the length of the VarDouble
  • 1-4 bits for the precision (0-15 digits of max precision)
  • 8-64 bits for the value
  • 12-75 bits total
• Write VarUIntLists (8, 16, 32, 64)
  • 10-70 bits for the length of the list
  • 2 bits for the length of the biggest VarUInt in the list
  • 8-64 bits per entry
  • 12-72 bits for the header
• Write VarIntLists (8, 16, 32, 64)
  • 10-70 bits for the length of the list
  • 2 bits for the length of the biggest VarInt in the list
  • 9-65 bits per entry (1 bit for the sign)
  • 12-72 bits for the header

Usage

import 'package:bits/bits.dart';

void main()
{
  // Create a buffer
  BitBuffer buffer = BitBuffer();
  
  // Write Data
  buffer.writeVarUInt(12); // Positive only (unsigned)
  buffer.writeVarInt(-12); // Positive and negative
  buffer.writeVarDouble(12.34); // Default precision is 8
  buffer.writeVarDouble(12.34, precision: 2); // 2 digits of precision
  buffer.writeVarUIntList([1, 2, 3, 4, 5]); // List of VarUInts
  buffer.writeVarIntList([-1, 2, -3, 4, -5]); // List of VarInts
  buffer.writeVarDoubleList([1.23, 4.56, 7.89], maxPrecision: 2); // List of VarDoubles
  
  // You can also write bits directly
  buffer.writeBits(0b10, 2); // Write 2 in 2 bits
  buffer.writeBits(0b101, 3); // Write 5 in 3 bits
  buffer.writeBits(28, buffer.getBitsNeeded(32)); // Write 28 in the minimum bits required to handle a maximum of 32.
  
  // Read Data (in the same order)
  print(buffer.readVarUInt()); // 12
  print(buffer.readVarInt()); // -12
  print(buffer.readVarDouble()); // 12.34
  print(buffer.readVarDouble(precision: 2)); // 12.34
  print(buffer.readVarUIntList()); // [1, 2, 3, 4, 5]
  print(buffer.readVarIntList()); // [-1, 2, -3, 4, -5]
  print(buffer.readVarDoubleList(maxPrecision: 2)); // [1.23, 4.56, 7.89]
  
  // You can also read bits directly
  print(buffer.readBits(2)); // 2
  print(buffer.readBits(3)); // 5
  print(buffer.readBits(buffer.getBitsNeeded(32))); // 28
}