Getting Started

Frent is on Nuget!

Caution

Frent is still in beta.

Warning

You will need to enable prerelease to see the package in many UIs.

dotnet add package Frent --version 0.5.4.3-beta

Note: Unity requires a different package

Creating a World

Start by importing Frent and Frent.Components (for component interfaces).

using Frent;
using Frent.Components;

To create a world, simply use its constructor

World world = new World();

A world is a collection of entities, and entities are made of components. Components can be almost any datatype, although its recommended to use structs.

Consider a player entity with the following components.

graph TD
    Entity --> Position["Position"]
    Entity --> Velocity["Velocity"]
    Entity --> Controller["Player Controller"]
    Entity --> Health["Health"]
    Entity --> Sprite["Sprite"]

Here, the Velocity component might interact with the Position component, and the PlayerController component might interact with the Velocity component when the W key is pressed.

Here is an example Position component - it just needs to specify enough data for a location.

struct Position(int x, int y)
{
    public int X = x;
    public int Y = y;
}

Here is an example Velocity component. By implementing the IComponent<Position> interface, we tell Frent that this Velocity struct is a component which interacts with its entity's Position and so needs it as an argument in its update method.

struct Velocity(int dx, int dy) : IComponent<Position>
{
    public int DX = dx;
    public int DY = dy;
    public void Update(ref Position pos)
    {
        pos.X += DX;
        pos.Y += DY;
    }
}

Let's make one last component to draw things to the console.

struct Character(char c) : IComponent<Position>
{
    public char Char = c;
    public void Update(ref Position pos)
    {
        Console.SetCursorPosition(pos.X, pos.Y);
        Console.Write(Char);
    }
}

To use these components, we must create an entity with them using the world.

//create
Entity entity = world.Create<Position, Velocity, Character>(new(4, 6), new(2, 0), new('@'));

//simulate 20 frames
for(int i = 0; i < 20; i++)
{
    world.Update();
    Thread.Sleep(100);
    Console.Clear();
}

Position finalPos = entity.Get<Position>();
Console.WriteLine($"Position: X: {finalPos.X} Y: {finalPos.Y}");

And that's it! You've got the basics of Frent. For more information about entities, systems, uniforms, and filtering world updates, check out the cookbook!

Full Code Sample

using System;
using System.Threading;
using Frent;
using Frent.Components;

World world = new World();

//create
Entity entity = world.Create<Position, Velocity, Character>(new(4, 6), new(2, 0), new('@'));

//simulate 20 frames
for (int i = 0; i < 20; i++)
{
    world.Update();
    Thread.Sleep(100);
    Console.Clear();
}

Position finalPos = entity.Get<Position>();
Console.WriteLine($"Position: X: {finalPos.X} Y: {finalPos.Y}");

struct Position(int x, int y)
{
    public int X = x;
    public int Y = y;
}

struct Velocity(int dx, int dy) : IComponent<Position>
{
    public int DX = dx;
    public int DY = dy;
    public void Update(ref Position pos)
    {
        pos.X += DX;
        pos.Y += DY;
    }
}

struct Character(char c) : IComponent<Position>
{
    public char Char = c;
    public void Update(ref Position pos)
    {
        Console.SetCursorPosition(pos.X, pos.Y);
        Console.Write(Char);
    }
}

Table of Contents

Getting Started

Caution

Warning

Creating a World