Trajectory

A lightweight immutable mathematics library for Java games, simulations and graphics

Part of the TANK Series.

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⚠️ Trajectory is currently in alpha. ⚠️

The API is expected to change frequently until v1.0.0.

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Features

Vectors

• Immutable Vector2, Vector3 and Vector4 types
• float, double and int variants
• Vector arithmetic
• Dot product
• Cross product
• Distance and length calculations
• Normalization (floating-point vectors)

Matrices (v0.2.0)

• Immutable Matrix2, Matrix3 and Matrix4 types
• float and double variants
• Matrix arithmetic
• Matrix × Matrix multiplication
• Matrix × Vector multiplication
• Determinant calculation
• Matrix transpose
• Matrix inversion
• Identity and zero matrices

Design Goals

• Lightweight
• Immutable by default
• Suitable for games, simulations and graphics
• Consistent API across numeric types

Installation

Currently, Trajectory is not on Maven Central. To use it, clone the repository and publish it to your local Maven Repository.

git clone https://github.com/breadcat-dev/trajectory.git
cd trajectory

Linux / MacOS

./gradlew publishToMavenLocal

Windows

./gradlew.bat publishToMavenLocal

Once installed, add the dependency:

Groovy

implementation "cat.breadcat:trajectory:<version>"

Kotlin DSL

implementation("cat.breadcat:trajectory:<version>")

Examples

Vectors

Vector3f position = new Vector3f(5, 2, 1);
Vector3f velocity = new Vector3f(1, 0, -2);

Vector3f next = position.add(velocity);

System.out.println(next);

Vector3f(6.0, 2.0, -1.0)

Matrices

Matrix4d m1 = new Matrix4d(
        0, 2, 1, 2,
        3, 0, 3, 4,
        5, 6, 0, 6,
        7, 8, 7, 0
);

Matrix4d m2 = Matrix4d.IDENTITY;
Matrix4d m3 = m1.divide(m2);

System.out.println(m3);

Matrix4d [
    [0.0 2.0 1.0 2.0]
    [3.0 0.0 3.0 4.0]
    [5.0 6.0 0.0 6.0]
    [7.0 8.0 7.0 0.0]
]

Dependencies:

• Toolbox - Github