jcw780 / wows_shell

C++ Ballistics Calculator for World of Warships

wows_shell

• C++ header only library for calculating shell performance in World of Warships
• Experimentally verified to be nearly identical to the World of Warships ballistics model

Legal

• All copyrighted material provided by Wargaming.net are owned by Wargaming.net.
• All other material is available under the MIT License.

Original Model Information & Source Code:

Original Model:

• Code
• Post-Penetration Formulas
  

Revised Model:

• Code

Features:

Shell Flight

Computes shell flight path.

At Impact:

Outputs:

• Angle of Impact
• Impact Velocity
• Raw, Belt/Deck, Normalization Adjusted Penetration
• Shell flight time (Real / In-game)
  

Ability to change trajectory computation method

• Forward Euler (default - also in-game method)
• Runge-Kutta 2 and 4
• Adams-Bashforth 5

Lateral Angles:

Computes lateral angles where penetration, AP fuzing, and ricochets occur while adjusting for impact angle and vertical armor inclination.

Definition: Angles where that represent the horizontal angling of a ship:

• Bow-in: 90 degrees
• Full-broadside: 0 degrees
  

Outputs:

• Maximum Lateral Angle for Penetration
• Minimum Lateral Angle for Fusing
• Ricochet Lateral Angles
  

Dispersion

Computes dispersion approximations based on experimental data.
Outputs:

• Dispersion Types:
  • Horizontal Dispersion
  • Vertical Dispersion
  • Area Dispersion
• Statistical Types
  • Max Dispersion
  • Standard Deviation of Dispersion
  • 50% Error Radius

Post-Penetration:

Shell detonation distance after penetration while adjusting for ship angling, and vertical armor inclinations.

Ability to modify the way the calculations are done

• Enable or Disable Normalization changing direction
• Linear estimation or full air drag modeling

Fitting:

Capability to fit shells to real world data using gradient descent.

• Air Drag Coefficient
• Krupp

Compatibility:

• Requires C++17 supporting compiler
• Supports multithreading and vectorization for improved performance

Extensions:

Python

• Requires Pybind11
• Tested with Python 3.7.4 (Anaconda), 3.8.5
• Available from PyPI pip install wows-shell

WebAssembly

• Requires Emscripten
• Used in https://github.com/jcw780/wows_ballistics

Future Goals:

• Wiki / Tutorial
• Extend more features to Python and WebAssembly
• Will continue to update the model when new information is acquired