A C# library for parsing and executing BulletML XML files. Define complex bullet patterns declaratively in XML and execute them at runtime in your shmup (shoot-em-up) game.
- Parse BulletML XML documents into an executable node tree
- Execute bullet patterns with per-frame updates
- Support for all BulletML elements: fire, direction, speed, acceleration, repeat, vanish, and more
- Parameterized pattern references for reusable bullet definitions
- Mathematical expression evaluation in node values (including
$rank,$rand, and custom callbacks) - Configurable time speed (slowdown/speedup) and scale (resize patterns)
- Async update support
- Built on MonoGame/XNA types
- .NET 8.0 or later
- MonoGame.Framework.DesktopGL 3.8+
- Equationator 5.x (mathematical expression parser)
- Vector2Extensions 5.x
Install via NuGet:
dotnet add package BulletMLLib
Or add to your .csproj:
<PackageReference Include="BulletMLLib" Version="5.*" />// 1. Implement IBulletManager
public class MyBulletManager : IBulletManager
{
public Random Rand { get; } = new Random();
public Dictionary<string, FunctionDelegate> CallbackFunctions { get; } = new();
public FunctionDelegate GameDifficulty { get; set; }
public Vector2 PlayerPosition(IBullet bullet) => _playerPos;
public IBullet CreateBullet() => new MyBullet(this);
public IBullet CreateTopBullet() => new MyBullet(this);
public void RemoveBullet(IBullet bullet) { /* mark inactive */ }
}
// 2. Inherit from Bullet
public class MyBullet : Bullet
{
private Vector2 _position;
public override float X { get => _position.X; set => _position.X = value; }
public override float Y { get => _position.Y; set => _position.Y = value; }
public MyBullet(IBulletManager manager) : base(manager) { }
public override void PostUpdate() { /* check bounds, draw, etc. */ }
}
// 3. Load and run a pattern
var manager = new MyBulletManager();
var pattern = new BulletPattern(manager);
pattern.ParseXML("patterns/spiral.xml");
var topBullet = manager.CreateTopBullet();
topBullet.X = 200;
topBullet.Y = 50;
topBullet.InitTopNode(pattern.RootNode);
// 4. Each frame:
topBullet.Update();- Getting Started -- step-by-step integration guide
- API Reference -- classes, interfaces, enums, and properties
- BulletML Pattern Guide -- writing BulletML XML scripts
- Architecture -- library internals and design
MIT