Go bindings for [raylib](https://www.raylib.com/), a simple and easy-to-use library to learn videogames programming.

![logo](https://goo.gl/XlIcXz)
## raylib-go
[![Build Status](https://github.com/gen2brain/raylib-go/actions/workflows/build.yml/badge.svg)](https://github.com/gen2brain/raylib-go/actions)
[![GoDoc](https://godoc.org/github.com/gen2brain/raylib-go/raylib?status.svg)](https://godoc.org/github.com/gen2brain/raylib-go/raylib)
[![Go Report Card](https://goreportcard.com/badge/github.com/gen2brain/raylib-go/raylib)](https://goreportcard.com/report/github.com/gen2brain/raylib-go/raylib)
[![Examples](https://img.shields.io/badge/learn%20by-examples-0077b3.svg?style=flat-square)](https://github.com/gen2brain/raylib-go/tree/master/examples)

Golang bindings for [raylib](http://www.raylib.com/), a simple and easy-to-use library to enjoy videogames programming.

raylib C source code is included and compiled together with bindings. Note that the first build can take a few minutes.

It is also possible to use raylib-go without cgo (Windows only; see requirements below).

### Requirements

##### Ubuntu

 apt-get install libgl1-mesa-dev libxi-dev libxcursor-dev libxrandr-dev libxinerama-dev libwayland-dev libxkbcommon-dev

##### Fedora

 dnf install mesa-libGL-devel libXi-devel libXcursor-devel libXrandr-devel libXinerama-devel wayland-devel libxkbcommon-devel

##### macOS

On macOS you need Xcode or Command Line Tools for Xcode.

##### Windows

###### cgo

On Windows you need C compiler, like [Mingw-w64](https://mingw-w64.org) or [TDM-GCC](http://tdm-gcc.tdragon.net/).
You can also build binary in [MSYS2](https://msys2.github.io/) shell.

To remove console window, build with `-ldflags "-H=windowsgui"`.

###### purego (without cgo, i.e. CGO_ENABLED=0)

Download the raylib.dll from the assets on the [releases page](https://github.com/raysan5/raylib/releases). It is contained in the `raylib-*_win64_msvc*.zip`.
Put the raylib.dll into the root folder of your project or copy it into `C:\Windows\System32` for a system-wide installation.

As of November 15, 2023, raylib 5.0 is the required version.

It is also possible to build the DLL yourself. You can find more info at [raylib's wiki](https://github.com/raysan5/raylib/wiki/Working-on-Windows).

##### Android

[Android example](https://github.com/gen2brain/raylib-go/tree/master/examples/others/android/example).

### Installation

 go get -v -u github.com/gen2brain/raylib-go/raylib

### Build tags

* `drm` - build for Linux native [DRM](https://en.wikipedia.org/wiki/Direct_Rendering_Manager) mode, including Raspberry Pi 4 and other devices (PLATFORM_DRM)
* `sdl` - build for [SDL](https://github.com/libsdl-org/SDL) backend (PLATFORM_DESKTOP_SDL)
* `rgfw` - build for [RGFW](https://github.com/ColleagueRiley/RGFW) backend (PLATFORM_DESKTOP_RGFW)
* `noaudio` - disables audio functions
* `opengl43` - uses OpenGL 4.3 backend
* `opengl21` - uses OpenGL 2.1 backend (default is 3.3 on desktop)
* `opengl11` - uses OpenGL 1.1 backend (pseudo OpenGL 1.1 style)
* `es2` - uses OpenGL ES 2.0 backend (can be used to link against [Google's ANGLE](https://github.com/google/angle))
* `es3` - experimental support for OpenGL ES 3.0
* `x11` - force X11 compatibility mode on Wayland (PLATFORM_DESKTOP/GLFW)

### Documentation

Documentation on [GoDoc](https://godoc.org/github.com/gen2brain/raylib-go/raylib). Also check raylib [cheatsheet](http://www.raylib.com/cheatsheet/cheatsheet.html). If you have problems or need assistance there is an active community in the #raylib-go channel of the [Raylib Discord Server](https://discord.gg/raylib) that can help.

### Example

```go
package main

import rl "github.com/gen2brain/raylib-go/raylib"

func main() {
	rl.InitWindow(800, 450, "raylib [core] example - basic window")
	defer rl.CloseWindow()

	rl.SetTargetFPS(60)

	for !rl.WindowShouldClose() {
		rl.BeginDrawing()

		rl.ClearBackground(rl.RayWhite)
		rl.DrawText("Congrats! You created your first window!", 190, 200, 20, rl.LightGray)

		rl.EndDrawing()
	}
}
```

Check more [examples](https://github.com/gen2brain/raylib-go/tree/master/examples) organized by raylib modules.

### Cross-compile (Linux)

To cross-compile for Windows install [MinGW](https://www.mingw-w64.org/) toolchain.

```
$ CGO_ENABLED=1 CC=x86_64-w64-mingw32-gcc GOOS=windows GOARCH=amd64 go build -ldflags "-s -w"
$ file basic_window.exe
basic_window.exe: PE32+ executable (console) x86-64 (stripped to external PDB), for MS Windows, 11 sections

$ CGO_ENABLED=1 CC=i686-w64-mingw32-gcc GOOS=windows GOARCH=386 go build -ldflags "-s -w"
$ file basic_window.exe
basic_window.exe: PE32 executable (console) Intel 80386 (stripped to external PDB), for MS Windows, 9 sections
```

To cross-compile for macOS install [OSXCross](https://github.com/tpoechtrager/osxcross) toolchain.

```
$ CGO_ENABLED=1 CC=x86_64-apple-darwin21.1-clang GOOS=darwin GOARCH=amd64 go build -ldflags "-linkmode external -s -w '-extldflags=-mmacosx-version-min=10.15'"
$ file basic_window
basic_window: Mach-O 64-bit x86_64 executable, flags:<NOUNDEFS|DYLDLINK|TWOLEVEL>

$ CGO_ENABLED=1 CC=aarch64-apple-darwin21.1-clang GOOS=darwin GOARCH=arm64 go build -ldflags "-linkmode external -s -w '-extldflags=-mmacosx-version-min=12.0.0'"
$ file basic_window
basic_window: Mach-O 64-bit arm64 executable, flags:<NOUNDEFS|DYLDLINK|TWOLEVEL|PIE>
```

### License

raylib-go is licensed under an unmodified zlib/libpng license. View [LICENSE](https://github.com/gen2brain/raylib-go/blob/master/LICENSE).

raylib-go

Terminal-based game engine for Go, built on top of Termbox.

## Termloop

[![Join the chat at https://gitter.im/JoelOtter/termloop](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/JoelOtter/termloop?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge) [![GoDoc](https://godoc.org/github.com/JoelOtter/termloop?status.svg)](http://godoc.org/github.com/JoelOtter/termloop)

![](_examples/images/maze.png)

Termloop is a pure Go game engine for the terminal, built on top of the excellent [Termbox](https://github.com/nsf/termbox-go). It provides a simple render loop for building games in the terminal, and is focused on making terminal game development as easy and as fun as possible.

Termloop is still under active development so changes may be breaking. I add any breaking changes to the [Changelog](https://github.com/JoelOtter/termloop/wiki/Changelog) - hopefully at this stage there shouldn't be too many. Pull requests and issues are *very* welcome, and do feel free to ask any questions you might have on the Gitter. I hope you enjoy using Termloop; I've had a blast making it.

## Installing
Install and update with `go get -u github.com/JoelOtter/termloop`

## Features

- Keyboard and mouse input
- Collision detection
- Render timers
- Level offsets to simulate 'camera' movement
- Debug logging
- Built-in entity types such as:
 - Framerate counters
 - Rectangles
 - Text
- Loading entities from ASCII art
- Loading colour maps from images
- Loading level maps from JSON
- Optional 'pixel mode' - draw two 'pixels' to a terminal character, doubling screen height at the expense of being able to render text.
- Pure Go - easy portability of compiled games, and cross-compilation built right in.

*To see what's on the roadmap, have a look at the [issue tracker](https://github.com/JoelOtter/termloop/issues).*

## termloop/extra

The Termloop extras are a collection of types and functions, the use of which will not result in a fully portable binary - that is, they have some external dependencies. However, if you're willing to require these dependencies in your project, they should integrate quite nicely with the rest of Termloop. Some of the included examples use these extras.

- Audio playback 
 - audio.go
 - Requirements: PortAudio and libsndfile

## Cool stuff built with Termloop
 
- [Included examples](https://github.com/JoelOtter/termloop/tree/master/_examples) (@JoelOtter)
- [Number Crusher](https://github.com/aquilax/number_crusher) (@aquilax)
- [Go Tapper](https://github.com/swapagarwal/gotapper) (@swapagarwal)
- [Frame Assault](https://github.com/Ariemeth/frame_assault) (@Ariemeth)
- [Minesweeper](https://github.com/ryanbaer/minesweeper-go) (@ryanbaer)
- [Termtank](https://github.com/TerrySolar/termtank) (@TerrySolar)
- [Snake](https://github.com/mattkelly/snake-go) (@mattkelly)
- [Go Man's Sky](https://rawktron.itch.io/go-mans-sky) (@rawktron)
- [conwaygo](https://github.com/buckley-w-david/conwaygo) (@buckley-w-david)
- [Doric (a Columns clone)](https://github.com/svera/doric) (@svera)
- [Terminal-based Snake](https://github.com/tristangoossens/snake-go) (@tristangoossens)
- [Sokoban](https://github.com/tristangoossens/sokoban-go) (@tristangoossens)
- [Gopher Typer](https://github.com/ScottBrooks/gopher_typer) (@scottbrooksca)
- [Tetris](https://bitbucket.org/cam73/tetris) (@cam73)
- [Gorched](https://github.com/zladovan/gorched) (@zladovan)
- [Go Invaders](https://github.com/afagundes/go-invaders) (@afagundes)

_Feel free to add yours with a pull request!_

## Tutorial
 
> More full documentation will be added to the Wiki soon. In the meantime, check out this tutorial, the [GoDoc](http://godoc.org/github.com/JoelOtter/termloop), or the [included examples](https://github.com/JoelOtter/termloop/tree/master/_examples). If you get stuck during this tutorial, worry not, the full source is [here](https://github.com/JoelOtter/termloop/blob/master/_examples/tutorial.go).

Creating a blank Termloop game is as simple as:

```go
package main

import tl "github.com/JoelOtter/termloop"

func main() {
	game := tl.NewGame()
	game.Start()
}
```

We can press Ctrl+C to exit. It's just a blank screen - let's make it a little more interesting.

Let's make a green background, because grass is really nice to run around on. We create a new level like so:

```go
level := tl.NewBaseLevel(tl.Cell{
	Bg: tl.ColorGreen,
	Fg: tl.ColorBlack,
	Ch: 'v',
})
```

Cell is a struct that represents one cell on the terminal. We can set its background and foreground colours, and the character that is displayed. Creating a [BaseLevel](http://godoc.org/github.com/JoelOtter/termloop#BaseLevel) in this way will fill the level with this Cell.

Let's make a nice pretty lake, too. We'll use a [Rectangle](http://godoc.org/github.com/JoelOtter/termloop#Rectangle) for this. We'll put the lake at position (10, 10), with width 50 and height 20. All measurements are in terminal characters! The last argument is the colour of the Rectangle.

```go
level.AddEntity(tl.NewRectangle(10, 10, 50, 20, tl.ColorBlue))
```

We don't need to use a Level - we can add entities directly to the [Screen](http://godoc.org/github.com/JoelOtter/termloop#Screen)! This is great for building a HUD, or a very simple app. However, if we want camera scrolling or collision detection, we're going to need to use a Level.

Putting together what we have so far:

```go
package main

import tl "github.com/JoelOtter/termloop"

func main() {
	game := tl.NewGame()
	level := tl.NewBaseLevel(tl.Cell{
		Bg: tl.ColorGreen,
		Fg: tl.ColorBlack,
		Ch: 'v',
	})
	level.AddEntity(tl.NewRectangle(10, 10, 50, 20, tl.ColorBlue))
	game.Screen().SetLevel(level)
	game.Start()
}
```

When we run it with `go run tutorial.go`, it looks like this:

![](_examples/images/tutorial01.png)

Pretty! Ish. OK, let's create a character that can walk around the environment. We're going to use object composition here - we'll create a new struct type, which extends an [Entity](http://godoc.org/github.com/JoelOtter/termloop#Entity).

To have Termloop draw our new type, we need to implement the [Drawable](http://godoc.org/github.com/JoelOtter/termloop#Drawable) interface, which means we need two methods: **Draw()** and **Tick()**. The Draw method defines how our type is drawn to the [Screen](http://godoc.org/github.com/JoelOtter/termloop#Screen) (Termloop's internal drawing surface), and the Tick method defines how we handle input.

We don't need to do anything special for `Draw`, and it's already handled by `Entity`, so we just need a `Tick`:

```go
type Player struct {
	*tl.Entity
}

func (player *Player) Tick(event tl.Event) {
	if event.Type == tl.EventKey { // Is it a keyboard event?
		x, y := player.Position()
		switch event.Key { // If so, switch on the pressed key.
		case tl.KeyArrowRight:
			player.SetPosition(x+1, y)
		case tl.KeyArrowLeft:
			player.SetPosition(x-1, y)
		case tl.KeyArrowUp:
			player.SetPosition(x, y-1)
		case tl.KeyArrowDown:
			player.SetPosition(x, y+1)
		}
	}
}
```

Now that we've built our Player type, let's add one to the level. I'm going to use the character '옷', because I think it looks a bit like a stick man.

```go
player := Player{tl.NewEntity(1, 1, 1, 1)}
// Set the character at position (0, 0) on the entity.
player.SetCell(0, 0, &tl.Cell{Fg: tl.ColorRed, Ch: '옷'})
level.AddEntity(&player)

```

![](_examples/images/tutorial02.png)

Running the game again, we see that we can now move around the map using the arrow keys. Neato! However, we can stroll across the lake just as easily as the grass. Our character isn't the Messiah, ~~he's a very naughty boy,~~ so let's add some collisions.

In Termloop, we have two interfaces that are used for collisions. Here they are.

```go
// Physical represents something that can collide with another
// Physical, but cannot process its own collisions.
// Optional addition to Drawable.
type Physical interface {
	Position() (int, int) // Return position, x and y
	Size() (int, int)     // Return width and height
}

// DynamicPhysical represents something that can process its own collisions.
// Implementing this is an optional addition to Drawable.
type DynamicPhysical interface {
	Position() (int, int) // Return position, x and y
	Size() (int, int)     // Return width and height
	Collide(Physical)     // Handle collisions with another Physical
}
```

It's pretty simple - if we want our object to be 'solid', then we implement Physical. If we want a solid object that actually does some processing on its own collisions, we implement DynamicPhysical! Essentially this just involves adding one more method to your type.

Note that, for performance reasons, you should try and have as few DynamicPhysicals as possible - for example, our Player will be one, but the lake need only be a Physical.

The Rectangle type already implements Physical, so we don't actually need to do anything. As well, Player already implements DynamicPhysical because of the embedded Entity. However, we want custom behaviour for Collide, so let's implement that method. For that, we'll have to modify our struct and Tick method, to keep track of the Player's previous position so we can move it back there if it collides with something.



```go
type Player struct {
	*tl.Entity
	prevX  int
	prevY  int
}

func (player *Player) Tick(event tl.Event) {
	if event.Type == tl.EventKey { // Is it a keyboard event?
		player.prevX, player.prevY = player.Position()
		switch event.Key { // If so, switch on the pressed key.
		case tl.KeyArrowRight:
			player.SetPosition(player.prevX+1, player.prevY)
		case tl.KeyArrowLeft:
			player.SetPosition(player.prevX-1, player.prevY)
		case tl.KeyArrowUp:
			player.SetPosition(player.prevX, player.prevY-1)
		case tl.KeyArrowDown:
			player.SetPosition(player.prevX, player.prevY+1)
		}
	}
}

func (player *Player) Collide(collision tl.Physical) {
	// Check if it's a Rectangle we're colliding with
	if _, ok := collision.(*tl.Rectangle); ok {
		player.SetPosition(player.prevX, player.prevY)
	}
}

```

Not too much extra code! We can now see that the Player can't walk out into the lake. If you see the Player overlap the lake slightly on one side, that's likely because the 'stick man' character we used isn't quite standard width.

We've now got something that looks a bit like a very simple exploration game. There's one more thing to add - let's have the camera scroll to keep the Player in the centre of the screen!

There isn't really a 'camera' in Termloop, like you might find in another graphics library. Instead, we set an offset, and the Screen draws our level appropriately. In our case it's really simple - all we need is for the Player to have a pointer to the Level, so we can make calls on it. Then we simply modify our Draw method, like so:

```go
type Player struct {
	*tl.Entity
	prevX  int
	prevY  int
	level  *tl.BaseLevel
}

func (player *Player) Draw(screen *tl.Screen) {
	screenWidth, screenHeight := screen.Size()
	x, y := player.Position()
	player.level.SetOffset(screenWidth/2-x, screenHeight/2-y)
  // We need to make sure and call Draw on the underlying Entity.
	player.Entity.Draw(screen)
}


// in func main
player := Player{
	Entity:   tl.NewEntity(1, 1, 1, 1),
	level: level,
}
```

That's all it takes. We should now see the camera moving. Of course, due to the static, repeating background, this doesn't look terribly convincing - it kind of looks like the player is standing still and everything else is moving! We could remedy this by, for example, only updating the offset when the player is closer to the edge of the screen. I'll leave it up to you as a challenge.

![](_examples/images/tutorial03.png)

We've now reached the end of our tutorial - I hope it's been useful! If you'd like to learn a little more about Termloop, more comprehensive documentation is coming on the Wiki. In the meantime, you can check out the [GoDoc](http://godoc.org/github.com/JoelOtter/termloop), or the [included examples](https://github.com/JoelOtter/termloop/tree/master/_examples). I'll be hanging out on the [Gitter](https://gitter.im/JoelOtter/termloop) too, if you have any questions. Have fun, and please do show me if you make something cool!


termloop

Data-oriented and cache-friendly 2D Grid library (TileMap), includes pathfinding, observers and import/export.

# Tile: Data-Oriented 2D Grid Engine


 <img width="340" height="152" src="./fixtures/logo.png">
 
 <img src="https://img.shields.io/github/go-mod/go-version/kelindar/tile" alt="Go Version">
 <a href="https://pkg.go.dev/github.com/kelindar/tile"><img src="https://pkg.go.dev/badge/github.com/kelindar/tile" alt="PkgGoDev"></a>
 <a href="https://goreportcard.com/report/github.com/kelindar/tile"><img src="https://goreportcard.com/badge/github.com/kelindar/tile" alt="Go Report Card"></a>
 <a href="https://opensource.org/licenses/MIT"><img src="https://img.shields.io/badge/License-MIT-blue.svg" alt="License"></a>
 <a href="https://coveralls.io/github/kelindar/tile"><img src="https://coveralls.io/repos/github/kelindar/tile/badge.svg" alt="Coverage"></a>


This repository contains a 2D tile map engine which is built with data and cache friendly ways. My main goal here is to provide a simple, high performance library to handle large scale tile maps in games.

- **Compact**. Each tile value is 4 bytes long and each grid page is 64-bytes long, which means a grid of 3000x3000 should take around 64MB of memory.
- **Thread-safe**. The grid is thread-safe and can be updated through provided update function. This allows multiple goroutines to read/write to the grid concurrently without any contentions. There is a spinlock per tile page protecting tile access.
- **Views & observers**. When a tile on the grid is updated, viewers of the tile will be notified of the update and can react to the changes. The idea is to allow you to build more complex, reactive systems on top of the grid.
- **Zero-allocation** (or close to it) traversal of the grid. The grid is pre-allocated entirely and this library provides a few ways of traversing it.
- **Path-finding**. The library provides a A\* pathfinding algorithm in order to compute a path between two points, as well as a BFS-based position scanning which searches the map around a point.

_Disclaimer_: the API or the library is not final and likely to change. Also, since this is just a side project of mine, don't expect this to be updated very often but please contribute!

# Grid & Tiles

The main entry in this library is `Grid` which represents, as the name implies a 2 dimentional grid which is the container of `Tile` structs. The `Tile` is essentially a cursor to a particular x,y coordinate and contains the following

- Value `uint32` of the tile, that can be used for calculating navigation or quickly retrieve sprite index.
- State set of `T comparable` that can be used to add additional information such as objects present on the tile. These things cannot be used for pathfinding, but can be used as an index.

Granted, uint32 value a bit small. The reason for this is the data layout, which is organised in thread-safe pages of 3x3 tiles, with the total size of 64 bytes which should neatly fit onto a cache line of a CPU.

In order to create a new `Grid[T]`, you first need to call `NewGridOf[T]()` method which pre-allocates the required space and initializes the tile grid itself. For example, you can create a 1000x1000 grid as shown below. The type argument `T` sets the type of the state objects. In the example below we want to create a new grid with a set of strings.

```go
grid := tile.NewGridOf[string](1000, 1000)
```

The `Each()` method of the grid allows you to iterate through all of the tiles in the grid. It takes an iterator function which is then invoked on every tile.

```go
grid.Each(func(p Point, t tile.Tile[string]) {
 // ...
})
```

The `Within()` method of the grid allows you to iterate through a set of tiles within a bounding box, specified by the top-left and bottom-right points. It also takes an iterator function which is then invoked on every tile matching the filter.

```go
grid.Within(At(1, 1), At(5, 5), func(p Point, t tile.Tile[string]) {
 // ...
})
```

The `At()` method of the grid allows you to retrieve a tile at a specific `x,y` coordinate. It simply returns the tile and whether it was found in the grid or not.

```go
if tile, ok := grid.At(50, 100); ok {
 // ...
}
```

The `WriteAt()` method of the grid allows you to update a tile at a specific `x,y` coordinate. Since the `Grid` itself is thread-safe, this is the way to (a) make sure the tile update/read is not racing and (b) notify observers of a tile update (more about this below).

```go
grid.WriteAt(50, 100, tile.Value(0xFF))
```

The `Neighbors()` method of the grid allows you to get the direct neighbors at a particular `x,y` coordinate and it takes an iterator funcion which is called for each neighbor. In this implementation, we are only taking direct neighbors (top, left, bottom, right). You rarely will need to use this method, unless you are rolling out your own pathfinding algorithm.

```go
grid.Neighbors(50, 100, func(point tile.Point, t tile.Tile[string]) {
 // ...
})
```

The `MergeAt()` method of the grid allows you to atomically update a value given a current value of the tile. For example, if we want to increment the value of a tile we can call this method with a function that increments the value. Under the hood, the increment will be done using an atomic compare-and-swap operation.

```go
grid.MergeAt(50, 100, func(v Value) Value {
 v += 1
 return v
})
```

The `MaskAt()` method of the grid allows you to atomically update only some of the bits at a particular `x,y` coordinate. This operation is as well thread-safe, and is actually useful when you might have multiple goroutines updating a set of tiles, but various goroutines are responsible for the various parts of the tile data. You might have a system that updates only a first couple of tile flags and another system updates some other bits. By using this method, two goroutines can update the different bits of the same tile concurrently, without erasing each other's results, which would happen if you just call `WriteAt()`.

```go
// assume byte[0] of the tile is 0b01010001
grid.MaskAt(50, 100,
 0b00101110, // Only last 2 bits matter
 0b00000011 // Mask specifies that we want to update last 2 bits
)

// If the original is currently: 0b01010001
// ...the result result will be: 0b01010010
```

# Pathfinding

As mentioned in the introduction, this library provides a few grid search / pathfinding functions as well. They are implemented as methods on the same `Grid` structure as the rest of the functionnality. The main difference is that they may require some allocations (I'll try to minimize it further in the future), and require a cost function `func(Tile) uint16` which returns a "cost" of traversing a specific tile. For example if the tile is a "swamp" in your game, it may cost higher than moving on a "plain" tile. If the cost function returns `0`, the tile is then considered to be an impassable obstacle, which is a good choice for walls and such.

The `Path()` method is used for finding a way between 2 points, you provide it the from/to point as well as costing function and it returns the path, calculated cost and whether a path was found or not. Note of caution however, avoid running it between 2 points if no path exists, since it might need to scan the entire map to figure that out with the current implementation.

```go
from := At(1, 1)
goal := At(7, 7)
path, distance, found := m.Path(from, goal, func(v tile.Value) uint16{
 if isImpassable(v) {
 return 0
 }
 return 1
})
```

The `Around()` method provides you with the ability to do a breadth-first search around a point, by providing a limit distance for the search as well as a cost function and an iterator. This is a handy way of finding things that are around the player in your game.

```go
point := At(50, 50)
radius := 5
m.Around(point, radius, func(v tile.Value) uint16{
 if isImpassable(v) {
 return 0
 }
 return 1
}, func(p tile.Point, t tile.Tile[string]) {
 // ... tile found
})
```

# Observers

Given that the `Grid` is mutable and you can make changes to it from various goroutines, I have implemented a way to "observe" tile changes through a `View()` method which creates a `View` structure and can be used to observe changes within a bounding box. For example, you might want your player to have a view port and be notified if something changes on the map so you can do something about it.

In order to use these observers, you need to first call the `View()` method and start polling from the `Inbox` channel which will contain the tile update notifications as they happen. This channel has a small buffer, but if not read it will block the update, so make sure you always poll everything from it.

In the example below we create a new 20x20 view on the grid and iterate through all of the tiles in the view.

```go
rect := tile.NewRect(0, 0, 20, 20)
view := grid.View(rect, func(p tile.Point, t tile.Tile){
 // Optional, all of the tiles that are in the view now
})

// Poll the inbox (in reality this would need to be with a select, and a goroutine)
for {
 update := <-view.Inbox
 // Do something with update.Point, update.Tile
}
```

The `MoveBy()` method allows you to move the view in a specific direction. It takes in a `x,y` vector but it can contain negative values. In the example below, we move the view upwards by 5 tiles. In addition, we can also provide an iterator and do something with all of the tiles that have entered the view (e.g. show them to the player).

```go
view.MoveBy(0, 5, func(p tile.Point, tile tile.Tile){
 // Every tile which entered our view
})
```

Similarly, `MoveAt()` method allows you to move the view at a specific location provided by the coordinates. The size of the view stays the same and the iterator will be called for all of the new tiles that have entered the view port.

```go
view.MoveAt(At(10, 10), func(p tile.Point, t tile.Tile){
 // Every tile which entered our view
})
```

The `Resize()` method allows you to resize and update the view port. As usual, the iterator will be called for all of the new tiles that have entered the view port.

```go
viewRect := tile.NewRect(10, 10, 30, 30)
view.Resize(viewRect, func(p tile.Point, t tile.Tile){
 // Every tile which entered our view
})
```

The `Close()` method should be called when you are done with the view, since it unsubscribes all of the notifications. Be careful, if you do not close the view when you are done with it, it will lead to memory leaks since it will continue to observe the grid and receive notifications.

```go
// Unsubscribe from notifications and close the view
view.Close()
```

# Save & Load

The library also provides a way to save the `Grid` to an `io.Writer` and load it from an `io.Reader` by using `WriteTo()` method and `ReadFrom()` function. Keep in mind that the save/load mechanism does not do any compression, but in practice you should [use to a compressor](https://github.com/klauspost/compress) if you want your maps to not take too much of the disk space - snappy is a good option for this since it's fast and compresses relatively well.

The `WriteTo()` method of the grid only requires a specific `io.Writer` to be passed and returns a number of bytes that have been written down to it as well if any specific error has occured. Below is an example of how to save the grid into a compressed buffer.

```go
// Prepare the output buffer and compressor
output := new(bytes.Buffer)
writer, err := flate.NewWriter(output, flate.BestSpeed)
if err != nil {
 // ...
}

defer writer.Close() // Make sure we flush the compressor
_, err := grid.WriteTo(writer) // Write the grid
if err != nil {
 // ...
}
```

The `ReadFrom()` function allows you to read the `Grid` from a particular reader. To complement the example above, the one below shows how to read a compressed grid using this function.

```go
// Prepare a compressed reader over the buffer
reader := flate.NewReader(output)

// Read the Grid
grid, err := ReadFrom(reader)
if err != nil{
 // ...
}
```

# Benchmarks

This library contains quite a bit of various micro-benchmarks to make sure that everything stays pretty fast. Feel free to clone and play around with them yourself. Below are the benchmarks which we have, most of them are running on relatively large grids.

```
cpu: Intel(R) Core(TM) i7-9700K CPU @ 3.60GHz
BenchmarkGrid/each-8 868 1358434 ns/op 0 B/op 0 allocs/op
BenchmarkGrid/neighbors-8 66551679 17.87 ns/op 0 B/op 0 allocs/op
BenchmarkGrid/within-8 27207 44753 ns/op 0 B/op 0 allocs/op
BenchmarkGrid/at-8 399067512 2.994 ns/op 0 B/op 0 allocs/op
BenchmarkGrid/write-8 130207965 9.294 ns/op 0 B/op 0 allocs/op
BenchmarkGrid/merge-8 124156794 9.663 ns/op 0 B/op 0 allocs/op
BenchmarkGrid/mask-8 100000000 10.67 ns/op 0 B/op 0 allocs/op
BenchmarkState/range-8 12106854 98.91 ns/op 0 B/op 0 allocs/op
BenchmarkState/add-8 48827727 25.43 ns/op 0 B/op 0 allocs/op
BenchmarkState/del-8 52110474 21.59 ns/op 0 B/op 0 allocs/op
BenchmarkPath/9x9-8 264586 4656 ns/op 16460 B/op 3 allocs/op
BenchmarkPath/300x300-8 601 1937662 ns/op 7801502 B/op 4 allocs/op
BenchmarkPath/381x381-8 363 3304134 ns/op 62394356 B/op 5 allocs/op
BenchmarkPath/384x384-8 171 7165777 ns/op 62394400 B/op 5 allocs/op
BenchmarkPath/3069x3069-8 31 36479106 ns/op 124836075 B/op 4 allocs/op
BenchmarkPath/3072x3072-8 30 34889740 ns/op 124837686 B/op 4 allocs/op
BenchmarkPath/6144x6144-8 142 7594013 ns/op 62395376 B/op 3 allocs/op
BenchmarkAround/3r-8 506857 2384 ns/op 385 B/op 1 allocs/op
BenchmarkAround/5r-8 214280 5539 ns/op 922 B/op 2 allocs/op
BenchmarkAround/10r-8 85723 14017 ns/op 3481 B/op 2 allocs/op
BenchmarkPoint/within-8 1000000000 0.2190 ns/op 0 B/op 0 allocs/op
BenchmarkPoint/within-rect-8 1000000000 0.2195 ns/op 0 B/op 0 allocs/op
BenchmarkStore/save-8 14577 82510 ns/op 8 B/op 1 allocs/op
BenchmarkStore/read-8 3199 364771 ns/op 647419 B/op 7 allocs/op
BenchmarkView/write-8 6285351 188.2 ns/op 48 B/op 1 allocs/op
BenchmarkView/move-8 10000 116953 ns/op 0 B/op 0 allocs/op
```

# Contributing

We are open to contributions, feel free to submit a pull request and we'll review it as quickly as we can. This library is maintained by [Roman Atachiants](https://www.linkedin.com/in/atachiants/)

## License

Tile is licensed under the [MIT License](LICENSE.md).

tile

Scalable game server framework with clustering support and client libraries for iOS, Android, Unity and others through the C SDK.

# pitaya [![Build Status][7]][8] [![Coverage Status][9]][10] [![GoDoc][1]][2] [![Docs][11]][12] [![Go Report Card][3]][4] [![MIT licensed][5]][6]

---

[1]: https://godoc.org/github.com/topfreegames/pitaya?status.svg
[2]: https://godoc.org/github.com/topfreegames/pitaya
[3]: https://goreportcard.com/badge/github.com/topfreegames/pitaya
[4]: https://goreportcard.com/report/github.com/topfreegames/pitaya
[5]: https://img.shields.io/badge/license-MIT-blue.svg
[6]: LICENSE
[7]: https://github.com/topfreegames/pitaya/actions/workflows/tests.yaml/badge.svg
[8]: https://github.com/topfreegames/pitaya/actions/workflows/tests.yaml
[9]: https://coveralls.io/repos/github/topfreegames/pitaya/badge.svg?branch=master
[10]: https://coveralls.io/github/topfreegames/pitaya?branch=master
[11]: https://readthedocs.org/projects/pitaya/badge/?version=latest
[12]: https://pitaya.readthedocs.io/en/latest/?badge=latest

Pitaya is an simple, fast and lightweight game server framework with clustering support and client libraries for iOS, Android, Unity and others through the [C SDK](https://github.com/topfreegames/libpitaya).
It provides a basic development framework for distributed multiplayer games and server-side applications.

## Getting Started

### Prerequisites

* [Go](https://golang.org/) >= 1.16
* [etcd](https://github.com/coreos/etcd) (optional, used for service discovery)
* [nats](https://github.com/nats-io/nats.go) (optional, used for sending and receiving rpc)
* [docker](https://www.docker.com) (optional, used for running etcd and nats dependencies on containers)

### Installing
clone the repo
```
git clone https://github.com/topfreegames/pitaya.git
```
setup pitaya dependencies
```
make setup
```

### Hacking pitaya

Here's one example of running Pitaya:

Start etcd (This command requires docker-compose and will run an etcd container locally. An etcd may be run without docker if preferred.)
```
cd ./examples/testing && docker compose up -d etcd
```
run the connector frontend server from cluster_grpc example
```
make run-cluster-grpc-example-connector
```
run the room backend server from the cluster_grpc example
```
make run-cluster-grpc-example-room
```

Now there should be 2 pitaya servers running, a frontend connector and a backend room. To send requests, use a REPL client for pitaya [pitaya-cli](https://github.com/topfreegames/pitaya/tree/main/pitaya-cli).

```
$ pitaya-cli
Pitaya REPL Client
>>> connect localhost:3250
connected!
>>> request room.room.entry
>>> sv-> {"code":0,"result":"ok"}
```

## Running the tests
```
make test
```
This command will run both unit and e2e tests.

## Contributing
#TODO

## Authors
* **TFG Co** - Initial work

## License
[MIT License](./LICENSE)

## Acknowledgements
* [nano](https://github.com/lonnng/nano) authors for building the framework pitaya is based on.
* [pomelo](https://github.com/NetEase/pomelo) authors for the inspiration on the distributed design and protocol

## Security
If you have found a security vulnerability, please email security@tfgco.com

## Resources
- Other pitaya-related projects
  + [libpitaya-cluster](https://github.com/topfreegames/libpitaya-cluster)
  + [libpitaya](https://github.com/topfreegames/libpitaya)
  + [pitaya-admin](https://github.com/topfreegames/pitaya-admin)
  + [pitaya-bot](https://github.com/topfreegames/pitaya-bot)
  + [pitaya-cli](https://github.com/topfreegames/pitaya/tree/main/pitaya-cli)
  + [pitaya-protos](https://github.com/topfreegames/pitaya-protos)

- Documents
  + [API Reference](https://godoc.org/github.com/topfreegames/pitaya)
  + [In-depth documentation](https://pitaya.readthedocs.io/en/latest/)

- Demo
  + [Implement a chat room in ~100 lines with pitaya and WebSocket](./examples/demo/chat) (adapted from [nano](https://github.com/lonnng/nano)'s example)
  + [Pitaya cluster mode example](./examples/demo/cluster)
  + [Pitaya cluster mode with protobuf protocol example](./examples/demo/cluster_protobuf)


Pitaya

# \*\*\*\*\*NOTICE\*\*\*\*\* 

This repo is not under active development anymore and has been archived. Continued development has been migrated to [Pixel2](https://github.com/gopxl/pixel). A big thank you to [faiface](https://github.com/faiface) for creating this awesome library and for all the hard work put into it. We encourage old and new users to check out the new repo and contribute to it.



<img src="logo/LOGOTYPE-HORIZONTAL-BLUE.png">

# Pixel [![Build Status](https://travis-ci.org/faiface/pixel.svg?branch=master)](https://travis-ci.org/faiface/pixel) [![GoDoc](https://godoc.org/github.com/faiface/pixel?status.svg)](https://godoc.org/github.com/faiface/pixel) [![Go Report Card](https://goreportcard.com/badge/github.com/faiface/pixel)](https://goreportcard.com/report/github.com/faiface/pixel) [![Join the chat at https://gitter.im/pixellib/Lobby](https://badges.gitter.im/pixellib/Lobby.svg)](https://gitter.im/pixellib/Lobby?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge) [![Discord Chat](https://img.shields.io/discord/699679031603494954)](https://discord.gg/q2DK4MP) 

A hand-crafted 2D game library in Go. Take a look into the [features](#features) to see what it can
do.

```
go get github.com/faiface/pixel
```

If you are using Modules (Go 1.11 or higher) and want a mutable copy of the source code:

```
git clone https://github.com/faiface/pixel # clone outside of $GOPATH
cd pixel
go install ./...
```

See [requirements](#requirements) for the list of libraries necessary for compilation.

All significant changes are documented in [CHANGELOG.md](CHANGELOG.md).

## Tutorial

The [Wiki of this repo](https://github.com/faiface/pixel/wiki) contains an extensive tutorial
covering several topics of Pixel. Here's the content of the tutorial parts so far:

- [Creating a Window](https://github.com/faiface/pixel/wiki/Creating-a-Window)
- [Drawing a Sprite](https://github.com/faiface/pixel/wiki/Drawing-a-Sprite)
- [Moving, scaling and rotating with Matrix](https://github.com/faiface/pixel/wiki/Moving,-scaling-and-rotating-with-Matrix)
- [Pressing keys and clicking mouse](https://github.com/faiface/pixel/wiki/Pressing-keys-and-clicking-mouse)
- [Drawing efficiently with Batch](https://github.com/faiface/pixel/wiki/Drawing-efficiently-with-Batch)
- [Drawing shapes with IMDraw](https://github.com/faiface/pixel/wiki/Drawing-shapes-with-IMDraw)
- [Typing text on the screen](https://github.com/faiface/pixel/wiki/Typing-text-on-the-screen)
- [Using a custom fragment shader](https://github.com/faiface/pixel/wiki/Using-a-custom-fragment-shader)

## [Examples](https://github.com/faiface/pixel-examples)

The [examples](https://github.com/faiface/pixel-examples) repository contains a few
examples demonstrating Pixel's functionality.

**To run an example**, navigate to it's directory, then `go run` the `main.go` file. For example:

```
$ cd pixel-examples/platformer
$ go run main.go
```

Here are some screenshots from the examples!

| [Lights](https://github.com/faiface/pixel-examples/blob/master/lights) | [Platformer](https://github.com/faiface/pixel-examples/blob/master/platformer) |
| --- | --- |
| ![Lights](https://github.com/faiface/pixel-examples/blob/master/lights/screenshot.png) | ![Platformer](https://github.com/faiface/pixel-examples/blob/master/platformer/screenshot.png) |

| [Smoke](https://github.com/faiface/pixel-examples/blob/master/smoke) | [Typewriter](https://github.com/faiface/pixel-examples/blob/master/typewriter) |
| --- | --- |
| ![Smoke](https://github.com/faiface/pixel-examples/blob/master/smoke/screenshot.png) | ![Typewriter](https://github.com/faiface/pixel-examples/blob/master/typewriter/screenshot.png) |

| [Raycaster](https://github.com/faiface/pixel-examples/blob/master/community/raycaster) | [Gizmo](https://github.com/Lallassu/gizmo) |
| --- | --- |
| ![Raycaster](https://github.com/faiface/pixel-examples/blob/master/community/raycaster/screenshot.png) | ![Gizmo](https://github.com/Lallassu/gizmo/blob/master/preview.png) |

## Features

Here's the list of the main features in Pixel. Although Pixel is still under heavy development,
**there should be no major breakage in the API.** This is not a 100% guarantee, though.

- Fast 2D graphics
 - Sprites
 - Primitive shapes with immediate mode style
 [IMDraw](https://github.com/faiface/pixel/wiki/Drawing-shapes-with-IMDraw) (circles, rectangles,
 lines, ...)
 - Optimized drawing with [Batch](https://github.com/faiface/pixel/wiki/Drawing-efficiently-with-Batch)
 - Text drawing with [text](https://godoc.org/github.com/faiface/pixel/text) package
- Audio through a separate [Beep](https://github.com/faiface/beep) library.
- Simple and convenient API
 - Drawing a sprite to a window is as simple as `sprite.Draw(window, matrix)`
 - Wanna know where the center of a window is? `window.Bounds().Center()`
 - [...](https://godoc.org/github.com/faiface/pixel)
- Full documentation and tutorial
- Works on Linux, macOS and Windows
- Window creation and manipulation (resizing, fullscreen, multiple windows, ...)
- Keyboard (key presses, text input) and mouse input without events
- Well integrated with the Go standard library
 - Use `"image"` package for loading pictures
 - Use `"time"` package for measuring delta time and FPS
 - Use `"image/color"` for colors, or use Pixel's own `color.Color` format, which supports easy
 multiplication and a few more features
 - Pixel uses `float64` throughout the library, compatible with `"math"` package
- Geometry transformations with
 [Matrix](https://github.com/faiface/pixel/wiki/Moving,-scaling-and-rotating-with-Matrix)
 - Moving, scaling, rotating
 - Easy camera implementation
- Off-screen drawing to Canvas or any other target (Batch, IMDraw, ...)
- Fully garbage collected, no `Close` or `Dispose` methods
- Full [Porter-Duff](http://ssp.impulsetrain.com/porterduff.html) composition, which enables
 - 2D lighting
 - Cutting holes into objects
 - Much more...
- Pixel let's you draw stuff and do your job, it doesn't impose any particular style or paradigm
- Platform and backend independent [core](https://godoc.org/github.com/faiface/pixel)
- Core Target/Triangles/Picture pattern makes it easy to create new drawing targets that do
 arbitrarily crazy stuff (e.g. graphical effects)
- Small codebase, ~5K lines of code, including the backend [glhf](https://github.com/faiface/glhf)
 package

 ## Related repositories

 Here are some packages which use Pixel:
 - [TilePix](https://github.com/bcvery1/tilepix) Makes handling TMX files built with [Tiled](https://www.mapeditor.org/) trivially easy to work with using Pixel.
 - [spriteplus](https://github.com/cebarks/spriteplus) Basic `SpriteSheet` and `Animation` implementations
 - [PixelUI](https://github.com/dusk125/pixelui) Imgui-based GUIs for Pixel
 - [pixelutils](https://github.com/dusk125/pixelutils) Variety of game related utilities (sprite packer, id generator, ticker, sprite loader, voronoia diagrams)

## Missing features

Pixel is in development and still missing few critical features. Here're the most critical ones.

- ~~Audio~~
- ~~Drawing text~~
- Antialiasing (filtering is supported, though)
- ~~Advanced window manipulation (cursor hiding, window icon, ...)~~
- Better support for Hi-DPI displays
- Mobile (and perhaps HTML5?) backend
- ~~More advanced graphical effects (e.g. blur)~~ (solved with the addition of GLSL effects)
- Tests and benchmarks
- Vulkan support

**Implementing these features will get us to the 1.0 release.** Contribute, so that it's as soon as
possible!

## Requirements

If you're using Windows and having trouble building Pixel, please check [this
guide](https://github.com/faiface/pixel/wiki/Building-Pixel-on-Windows) on the
[wiki](https://github.com/faiface/pixel/wiki).

[PixelGL](https://godoc.org/github.com/faiface/pixel/pixelgl) backend uses OpenGL to render
graphics. Because of that, OpenGL development libraries are needed for compilation. The dependencies
are same as for [GLFW](https://github.com/go-gl/glfw).

The OpenGL version used is **OpenGL 3.3**.

- On macOS, you need Xcode or Command Line Tools for Xcode (`xcode-select --install`) for required
 headers and libraries.
- On Ubuntu/Debian-like Linux distributions, you need `libgl1-mesa-dev` and `xorg-dev` packages.
- On CentOS/Fedora-like Linux distributions, you need `libX11-devel libXcursor-devel libXrandr-devel
 libXinerama-devel mesa-libGL-devel libXi-devel libXxf86vm-devel` packages.
- See [here](http://www.glfw.org/docs/latest/compile.html#compile_deps) for full details.

**The combination of Go 1.8, macOS and latest XCode seems to be problematic** as mentioned in issue
[#7](https://github.com/faiface/pixel/issues/7). This issue is probably not related to Pixel.
**Upgrading to Go 1.8.1 fixes the issue.**

## Contributing

Join us in the [Discord Chat!](https://discord.gg/q2DK4MP)

Pixel is in, let's say, mid-stage of development. Many of the important features are here, some are
missing. That's why **contributions are very important and welcome!** All alone, I will be able to
finish the library, but it'll take a lot of time. With your help, it'll take much less. I encourage
everyone to contribute, even with just an idea. Especially welcome are **issues** and **pull
requests**.

**However, I won't accept everything. Pixel is being developed with thought and care.** Each
component was designed and re-designed multiple times. Code and API quality is very important here.
API is focused on simplicity and expressiveness.

When contributing, keep these goals in mind. It doesn't mean that I'll only accept perfect pull
requests. It just means that I might not like your idea. Or that your pull requests could need some
rewriting. That's perfectly fine, don't let it put you off. In the end, we'll just end up with a
better result.

Take a look at [CONTRIBUTING.md](CONTRIBUTING.md) for further information.

## License

[MIT](LICENSE)

Pixel

Cross-platform (Windows/Linux/Mac) library for creating desktop games using a minimal API.

prototype
=========

Simply prototype 2D games using an easy, minimal interface that lets you draw simple primitives and images on the screen, easily handle mouse and keyboard events and play sounds.

![Games](https://github.com/gonutz/prototype/blob/master/samples/screenshots/games.png)

Installation
------------

Install the [Go programming language](https://golang.org/dl/). After clicking the download link you will be referred to the installation instructions for your specific operating system.

Install [Git](https://git-scm.com/downloads) and make it available in the PATH so the go tool can use it.

For Linux and OS X you need a C compiler installed. On Windows this is not necessary.

On Linux there are two backends available, GLFW and SDL2. For GLFW you need these libraries installed (tested on Linux Mint, other distros might be slightly different):

`libx11-dev libxrandr-dev libgl1-mesa-dev libxcursor-dev libxinerama-dev libxi-dev`

GLFW is used by default. To use SDL2 you need to add `-tags sdl2` to your Go builds, e.g. `go run -tags sdl2 main.go`. Also you need the SDL2 libraries installed:

`libsdl2-dev libsdl2-mixer-dev libsdl2-image-dev`


Install the library and samples by running the following on your command line:

	go get github.com/gonutz/prototype/...

Documentation
-------------

For a description of all library functions, see [the godoc page](http://godoc.org/github.com/gonutz/prototype/draw) for this project. Note that most of the functionality is in the Window interface and hence the descriptions are listed as code comments in the source for that type.

Example
-------

```Go
package main

import (
	"math"

	"github.com/gonutz/prototype/draw"
)

func main() {
	draw.RunWindow("Title", 640, 480, update)
}

func update(window draw.Window) {
	// find the screen center
	w, h := window.Size()
	centerX, centerY := w/2, h/2

	// draw a button in the center of the screen
	mouseX, mouseY := window.MousePosition()
	mouseInCircle := math.Hypot(float64(mouseX-centerX), float64(mouseY-centerY)) < 20
	color := draw.DarkRed
	if mouseInCircle {
		color = draw.Red
	}
	window.FillEllipse(centerX-20, centerY-20, 40, 40, color)
	window.DrawEllipse(centerX-20, centerY-20, 40, 40, draw.White)
	if mouseInCircle {
		window.DrawScaledText("Close!", centerX-40, centerY+25, 1.6, draw.Green)
	}

	// check all mouse clicks that happened during this frame
	for _, click := range window.Clicks() {
		dx, dy := click.X-centerX, click.Y-centerY
		squareDist := dx*dx + dy*dy
		if squareDist <= 20*20 {
			// close the window and end the application
			window.Close()
		}
	}
}
```
	
This example displays a window with a round button in the middle to close it. It demonstrates some basic drawing and event handling code.

prototype

Build your own Game-Engine based on the Entity Component System concept in Golang.

<img src="https://github.com/andygeiss/ecs/blob/master/logo.png?raw=true" />


# ECS - Entity Component System

[![License](https://img.shields.io/github/license/andygeiss/ecs)](https://github.com/andygeiss/ecs/blob/master/LICENSE)
[![Releases](https://img.shields.io/github/v/release/andygeiss/ecs)](https://github.com/andygeiss/ecs/releases)
[![Go Report Card](https://goreportcard.com/badge/github.com/andygeiss/ecs)](https://goreportcard.com/report/github.com/andygeiss/ecs)
[![Codacy Grade Badge](https://app.codacy.com/project/badge/Grade/b4f4c9b35f4b46d8bf19f73379864b45)](https://app.codacy.com/gh/andygeiss/ecs/dashboard?utm_source=gh&utm_medium=referral&utm_content=&utm_campaign=Badge_grade)
[![Codacy Coverage Badge](https://app.codacy.com/project/badge/Coverage/b4f4c9b35f4b46d8bf19f73379864b45)](https://app.codacy.com/gh/andygeiss/ecs/dashboard?utm_source=gh&utm_medium=referral&utm_content=&utm_campaign=Badge_coverage)
[![Maintainability](https://api.codeclimate.com/v1/badges/5a2fd230f2eae6f244f2/maintainability)](https://codeclimate.com/github/andygeiss/ecs/maintainability)

Build your own Game-Engine based on the Entity Component System concept in Golang.

## Features

- [x] Provide an **easy-to-use** framework to build a game engine from scratch.
- [x] **No dependencies** to other modules or specific game libraries - Feel free to use what fits your needs.
- [x] **Minimum overhead** - use only what is really needed.

### Example engine

See [engine-example](https://github.com/andygeiss/engine-example) for a basic
implementation using [raylib](https://www.raylib.com).

## Walkthrough

### Project layout

At first we create a basic project layout:

```bash
mkdir ecs-example
cd ecs-example
go mod init example
mkdir components systems
```

Next we create a `main.go` with the following content:

```go
package main

import (
 "github.com/andygeiss/ecs"
)

func main() {
 em := ecs.NewEntityManager()
 sm := ecs.NewSystemManager()
 de := ecs.NewDefaultEngine(em, sm)
 de.Setup()
 defer de.Teardown()
 de.Run()
}
```

The execution of the program leads to an endless loop, as our engine is not yet
able to react to user input.

### The movement system

A system needs to implement the methods defined by the interface
[System](https://github.com/andygeiss/ecs/blob/master/core/system.go).
So we create a new file locally at `systems/movement.go`:

```go
package systems

import (
 "github.com/andygeiss/ecs"
)

type movementSystem struct{}

func (a *movementSystem) Process(em ecs.EntityManager) (state int) {
 // This state simply tells the engine to stop after the first call.
 return ecs.StateEngineStop
}

func (a *movementSystem) Setup() {}

func (a *movementSystem) Teardown() {}

func NewMovementSystem() ecs.System {
 return &movementSystem{}
}
```

Now we can add the following lines to `main.go`:

```go
sm := ecs.NewSystemManager()
sm.Add(systems.NewMovementSystem()) // <--
de := ecs.NewDefaultEngine(em, sm)
```

If we start our program now, it returns immediately without looping forever.

### The player entity

A game engine usually processes different types of components that represent
information about the game world itself. A component only represents the data,
and the systems are there to implement the behavior or game logic and change
these components. Entities are simply a composition of components that provide
a scalable data-oriented architecture.

A component needs to implement the methods defined by the interface
[Component](https://github.com/andygeiss/ecs/blob/master/core/component.go).
Let's define our `Player` components by first creating a mask at
`components/components.go`:

```go
package components

const (
 MaskPosition = uint64(1 << 0)
 MaskVelocity = uint64(1 << 1)
)
```

Then create a component for `Position` and `Velocity` by creating
corresponding files such as `components/position.go`:

```go
package components

type Position struct {
 X float32 `json:"x"`
 Y float32 `json:"y"`
}

func (a *Position) Mask() uint64 {
 return MaskPosition
}

func (a *Position) WithX(x float32) *Position {
 a.X = x
 return a
}

func (a *Position) WithY(y float32) *Position {
 a.Y = y
 return a
}

func NewPosition() *Position {
 return &Position{}
}
```

Now we can add the following lines to `main.go`:

```go
em := ecs.NewEntityManager()
em.Add(ecs.NewEntity("player", []ecs.Component{ // <--
components.NewPosition().
 WithX(10).
 WithY(10),
components.NewVelocity().
 WithX(100).
 WithY(100),
})) // -->
```

### Extend the movement system

Our final step is to add behavior to our movement system:

```go
func (a *movementSystem) Process(em ecs.EntityManager) (state int) {
 for _, e := range em.FilterByMask(components.MaskPosition | components.MaskVelocity) {
 position := e.Get(components.MaskPosition).(*components.Position)
 velocity := e.Get(components.MaskVelocity).(*components.Velocity)
 position.X += velocity.X * rl.GetFrameTime()
 position.Y += velocity.Y * rl.GetFrameTime()
 }
 return ecs.StateEngineStop
}
```

The movement system now moves every entity which has a position and velocity component.

We can replace `ecs.StateEngineStop` with `ecs.StateEngineContinue` later if we add
another system to handle user input.

A rendering system is also essential for a game, so you can use game libraries
such as [raylib](https://www.raylib.com) or
[SDL](https://github.com/libsdl-org/SDL).
This system could look like this with raylib:

```go
// ...
func (a *renderingSystem) Setup() {
 rl.InitWindow(a.width, a.height, a.title)
}

func (a *renderingSystem) Process(em core.EntityManager) (state int) {
 // First check if app should stop.
 if rl.WindowShouldClose() {
 return core.StateEngineStop
 }
 // Clear the screen
 if rl.IsWindowReady() {
 rl.BeginDrawing()
 rl.ClearBackground(rl.Black)
 rl.DrawFPS(10, 10)
 rl.EndDrawing()
 }
 return core.StateEngineContinue
}

func (a *renderingSystem) Teardown() {
 rl.CloseWindow()
}
```

Engo is an open-source 2D game engine written in Go. It follows the Entity-Component-System paradigm.

# Engo
[![GoDoc](https://godoc.org/github.com/EngoEngine/engo?status.svg)](https://godoc.org/github.com/EngoEngine/engo)
[![Join the chat at https://gitter.im/EngoEngine/engo](https://badges.gitter.im/EngoEngine/engo.svg)](https://gitter.im/EngoEngine/engo?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge) ![License](https://img.shields.io/badge/License-MIT-blue.svg)
[![Build Status](https://travis-ci.org/EngoEngine/engo.svg?branch=master)](https://travis-ci.org/EngoEngine/engo)
[![Build status](https://ci.appveyor.com/api/projects/status/019qc8hncmhnje83?svg=true)](https://ci.appveyor.com/project/otraore/engo)
[![Go Report Card](https://goreportcard.com/badge/github.com/EngoEngine/engo)](https://goreportcard.com/report/github.com/EngoEngine/engo)
[![Coverage Status](https://coveralls.io/repos/github/EngoEngine/engo/badge.svg?branch=master)](https://coveralls.io/github/EngoEngine/engo?branch=master)

A cross-platform game engine written in Go following an interpretation of the Entity Component System paradigm. Engo is
currently compilable for Mac OSX, Linux and Windows. With the release of Go 1.4, supporting Android and the inception of
iOS compatibility, mobile has been be added as a release target. Web support
([wasm](https://github.com/golang/go/wiki/WebAssembly)) is also available.

v1.0 is now available! To celebrate, there will be a game jam coming soon to celebrate the release, start actually
building things and hopefully find any issues. Updates for this will come soon.

## Getting in touch / Contributing

We have a [gitter](https://gitter.im/EngoEngine/engo) chat for people to join who want to further discuss `engo`. We are happy to discuss bugs, feature requests and would love to hear about the projects you are building!

## Getting Started

### Theory: `common` vs `engo`

There are currently two major important packages within this repository: `github.com/EngoEngine/engo` and `github.com/EngoEngine/engo/common`.

The top level `engo` package contains the functionality of creating windows, starting the game, creating an OpenGL
context and handling input. It is designed to be used with Systems designed as per `github.com/EngoEngine/ecs` specifications.
The `common` package contains our ECS implementations of common game development Systems like a  `RenderSystem` or
`CameraSystem`.

### Practice: Getting it to Run

1. First, you have to install some dependencies:
  1. If you're running on Debian/Ubuntu:
    `sudo apt-get install libasound2-dev libglu1-mesa-dev freeglut3-dev mesa-common-dev xorg-dev libgl1-mesa-dev git-all`
  2. If you're running on Windows you'll need a gcc compiler that the go tool can use and have `gcc.exe` in your PATH environmental variable. We recommend [Mingw](http://mingw-w64.org/doku.php/start) since it has been tested. You'll also need git installed, we recommend getting it from [The official Git site](http://git-scm.com/download/win)
  3. If you're on OSX, you will also need Git. You can find instructions [here](https://git-scm.com/book/en/v2/Getting-Started-Installing-Git#Installing-on-Mac). You can also use homebrew to install git as well. [Open an issue if you have any issues](https://github.com/EngoEngine/engo/issues/new)
2. Then, you can go get it:
`go get -u github.com/EngoEngine/engo`
  1. You may also want to get the dependencies of platform specific builds, so that build tools like godef can use them:
  `go get -u -tags js ./...`
  `go get -u -tags android ./...`
3. Now, you have two choices:
  1. Visit [our website](https://engoengine.github.io/), which hosts a full-blown tutorial series on how to create your own game, and on top of that, has some conceptual explanations;
  2. Check out some demos in our [demos folder](https://github.com/EngoEngine/engo/tree/master/demos).
4. Finally, if you run into problems, if you've encountered a bug, or want to request a feature, feel free to shoot
us a DM or [create an issue](https://github.com/EngoEngine/engo/issues/new).

## Breaking Changes Since v1.0
Engo is always undergoing a lot of optimizations and constantly gets new features. However, this sometimes means things break. In order to make transitioning easier for you,
we have a list of those changes, with the most recent being at the top. If you run into any problems, please contact us at [gitter](https://gitter.im/EngoEngine/engo).

* TMXObject Width and Height is in pixels, and can be fractional. This has changed from an int to a float64.
* TMXTileset now uses a Spritesheet instead of a Texture. This helps keep track of the guid better and allows the gid to not start at zero and have skips in it, as well as for borders and spacing in the tile sheet.
* TMX Level's objects have all been rolled into Object rather than have separate things like "PolyLineObject". This is to be
consistent with the TMX format.
* The Shader interface now has a `SetCamera(*CameraSystem)` method. This method allows shaders to automatically update the camera system as it changes, such as between scenes or when the camera system is added.
* The domain engo.io has expired. Now use `github.com/EngoEngine/engo` as the import path, and the site can be located at
engoengine.github.io

## Roadmap to v1.1
A list of issues for v1.1 can be found [here](https://github.com/EngoEngine/engo/issues/552). There's always room
for improvement! Feel free to submit proposals, open issues, and let us know how we can improve!

## History

Engo, originally known as `Engi` was written by [ajhager](https://github.com/ajhager) as a general purpose Go game engine. With a desire to build it into an "ECS" game engine, it was forked to `github.com/paked/engi`. After passing through several iterations, it was decided that the project would be rebranded and rereleased as Engo on its own GitHub organization.

## Credits

Thank you to everyone who has worked on, or with `Engo`. None of this would be possible without you, and your help has been truly amazing.

- [ajhager](https://github.com/ajhager): Building the original `engi`, which engo was based off of
- [paked](https://github.com/paked): Adding ECS element, project maintenance and management
- [Newbrict](https://github.com/Newbrict): Font rendering, TMX support
- [EtienneBruines](https://github.com/EtienneBruines): Rewriting the OpenGL code, maintenance and helping redesign the API
- [otraore](https://github.com/otraore): Adding in GopherJS support, maintenance
- [Everyone else who has submitted PRs or issues over the years, to any iteration of the project](https://github.com/EngoEngine/engo/graphs/contributors)

These are 3rd party projects that have made `engo` possible.
- The original [engi](https://github.com/ajhager/engi) game engine which engo was based off of ([BSD license](https://github.com/ajhager/engi/blob/master/LICENSE))
- [Oto](https://github.com/hajimehoshi/oto), a low-level cross-platform library to play sound. The AudioSystem uses this and is based on
the audio package used in [Ebiten](https://github.com/hajimehoshi/ebiten).


engo

[![PkgGoDev](https://pkg.go.dev/badge/github.com/s0rg/fantasyname)](https://pkg.go.dev/github.com/s0rg/fantasyname)
[![License](https://img.shields.io/github/license/s0rg/fantasyname)](https://github.com/s0rg/fantasyname/blob/main/LICENSE)
[![Go Version](https://img.shields.io/github/go-mod/go-version/s0rg/fantasyname)](go.mod)
[![Tag](https://img.shields.io/github/v/tag/s0rg/fantasyname?sort=semver)](https://github.com/s0rg/fantasyname/tags)
[![Mentioned in Awesome Go](https://awesome.re/mentioned-badge.svg)](https://github.com/avelino/awesome-go)

[![CI](https://github.com/s0rg/fantasyname/workflows/ci/badge.svg)](https://github.com/s0rg/fantasyname/actions?query=workflow%3Aci)
[![Go Report Card](https://goreportcard.com/badge/github.com/s0rg/fantasyname)](https://goreportcard.com/report/github.com/s0rg/fantasyname)
[![Maintainability](https://api.codeclimate.com/v1/badges/95826f2eb57b89cefe70/maintainability)](https://codeclimate.com/github/s0rg/fantasyname/maintainability)
[![Test Coverage](https://api.codeclimate.com/v1/badges/95826f2eb57b89cefe70/test_coverage)](https://codeclimate.com/github/s0rg/fantasyname/test_coverage)
![Issues](https://img.shields.io/github/issues/s0rg/fantasyname)

# fantasyname

This is a golang implementation of [name generator described at RinkWorks](http://rinkworks.com/namegen/),
its based on [https://github.com/skeeto/fantasyname](https://github.com/skeeto/fantasyname) code.

# example

How it looks like:
```go
import (
 "fmt"
 "log"
 "time"
 "math/rand"

 fn "github.com/s0rg/fantasyname"
)

func main() {
 rand.Seed(time.Now().UnixNano())

 gen, err := fn.Compile("sV'i", fn.Collapse(true), fn.RandFn(rand.Intn))
 if err != nil {
 log.Fatal(err)
 }

 fmt.Println(gen.String()) // will print something like: entheu'loaf
}
```

[Here](https://github.com/s0rg/fantasyname/blob/master/_example/main.go) is a full example.

You can run it with `go run _example/main.go` to see results.

# pattern syntax

The letters `s`, `v`, `V`, `c`, `B`, `C`, `i`, `m`, `M`, `D`, and `d` represent different types of random replacements:

 - `s` - generic syllable
 - `v` - vowel
 - `V` - vowel or vowel combination
 - `c` - consonant
 - `B` - consonant or consonant combination suitable for beginning a word
 - `C` - consonant or consonant combination suitable anywhere in a word
 - `i` - insult
 - `m` - mushy name
 - `M` - mushy name ending
 - `D` - consonant suited for a stupid person's name
 - `d` - syllable suited for a stupid person's name (begins with a vowel)

Everything else is emitted literally.

All characters between parenthesis `()` are emitted literally. For example, the pattern `s(dim)`,
emits a random generic syllable followed by `dim`.

Characters between angle brackets `<>` emit patterns from the table above.
Imagine the entire pattern is wrapped in one of these.

In both types of groupings, a vertical bar `|` denotes a random choice. Empty groups are allowed.
For example, `(foo|bar)` emits either `foo` or `bar`. The pattern `<c|v|>` emits a constant, vowel,
or nothing at all.

An exclamation point `!` means to capitalize the component that follows it. For example,
`!(foo)` will emit `Foo` and `v!s` will emit a lowercase vowel followed by a capitalized syllable, like `eRod`.

fantasyname

<img width="150" src="https://github.com/g3n/g3nd/blob/master/data/images/g3n_logo.png" alt="G3N Banner"/>

 <a href="https://godoc.org/github.com/g3n/engine"><img src="https://godoc.org/github.com/g3n/engine?status.svg" alt="Godoc"></img></a>
 <a href="https://goreportcard.com/report/github.com/g3n/engine"><img src="https://goreportcard.com/badge/github.com/g3n/engine" alt="Go Report Card"/></a>
 <a href="https://discord.gg/NfaeVr8zDg"><img src="https://img.shields.io/badge/Discord-G3N-blue" alt="Discord"/></a>
 

<h1 align="center">G3N - Go 3D Game Engine</h1>

**G3N** (pronounced "gen") is an OpenGL 3D Game Engine written in Go.
It can be used to write cross-platform Go applications that show rich and dynamic 3D representations - not just games. A basic integrated GUI framework is provided, and 3D spatial audio is supported through [OpenAL](https://www.openal.org/).

### **To see G3N in action try the [G3N demo](https://github.com/g3n/g3nd) or the [Gokoban](https://github.com/danaugrs/gokoban) award winning game.**


 <img style="float: right;" src="https://raw.githubusercontent.com/g3n/g3nd/master/data/images/g3nd_screenshots.png" alt="G3ND In Action"/>


## Highlighted Projects Using G3N

* [Gokoban - 3D Puzzle Game (_1st place in the 2017 Gopher Game Jam_)](https://github.com/danaugrs/gokoban)
* [go-tsne (_dimensionality reduction particularly well suited for visualizing high-dimensional datasets_)](https://github.com/danaugrs/go-tsne)
* [G3N Server-Side Rendering](https://github.com/moethu/webg3n)

## Dependencies

**Go 1.8+** is required. The engine also requires the system to have an **OpenGL driver** and a **GCC-compatible C compiler**.

On Unix-based systems the engine depends on some C libraries that can be installed using the appropriate distribution package manager. See below for OS specific requirements.

### Ubuntu/Debian-like

 $ sudo apt-get install xorg-dev libgl1-mesa-dev libopenal1 libopenal-dev libvorbis0a libvorbis-dev libvorbisfile3

### Fedora

 $ sudo dnf -y install xorg-x11-proto-devel mesa-libGL mesa-libGL-devel openal-soft openal-soft-devel libvorbis libvorbis-devel glfw-devel libXi-devel libXxf86vm-devel

### CentOS 7

Enable the EPEL repository:

 $ sudo yum -y install https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm
 
Then install the same packages as for Fedora - remember to use `yum` instead of `dnf` for the package installation command.
 
### Arch

 $ sudo pacman -S base-devel xorg-server mesa openal libvorbis
 
### Void

 $ sudo xbps-install git xorg-server-devel base-devel libvorbis-devel libvorbis libXxf86vm-devel libXcursor-devel libXrandr-devel libXinerama-devel libopenal libopenal-devel libglvnd-devel
 
### Windows

We tested the Windows build using the [mingw-w64](https://mingw-w64.org) toolchain (you can download [this file](https://sourceforge.net/projects/mingw-w64/files/Toolchains%20targetting%20Win64/Personal%20Builds/mingw-builds/8.1.0/threads-posix/seh/x86_64-8.1.0-release-posix-seh-rt_v6-rev0.7z) in particular).

The necessary [audio DLLs](audio/windows/bin) are supplied and need to be added to your PATH.
If you would like to build the DLLs yourself you can find the libraries' source code and build instructions [here](audio/windows).

### macOS

Install the development files of OpenAL and Vorbis using [Homebrew](https://brew.sh/):

 brew install libvorbis openal-soft

## Installation

The following set of commands will download and install the engine along with all its Go dependencies:
 
```
git clone https://github.com/g3n/engine g3n-engine
cd g3n-engine
go install ./...
```

## Features

* Cross-platform: Windows, Linux, and macOS. (WebAssembly is 90% complete!)
* Integrated GUI (graphical user interface) with many widgets
* Hierarchical scene graph - nodes can contain other nodes
* 3D spatial audio via OpenAL (.wav, .ogg)
* Real-time lighting: ambient, directional, point, and spot lights
* Physically-based rendering: fresnel reflectance, geometric occlusion, microfacet distribution
* Model loaders: glTF (.gltf, .glb), Wavefront OBJ (.obj), and COLLADA (.dae)
* Geometry generators: box, sphere, cylinder, torus, etc...
* Geometries support morph targets and multimaterials
* Support for animated sprites based on sprite sheets
* Perspective and orthographic cameras
* Text image generation and support for TrueType fonts
* Image textures can be loaded from GIF, PNG or JPEG files
* Animation framework for position, rotation, and scale of objects
* Support for user-created GLSL shaders: vertex, fragment, and geometry shaders
* Integrated basic physics engine (experimental/incomplete)
* Support for HiDPI displays


 <img style="float: right;" src="https://github.com/g3n/g3n.github.io/raw/master/img/g3n_banner_small.png" alt="G3N Banner"/>


## Hello G3N

The code below is a basic "hello world" application ([hellog3n](https://github.com/g3n/demos/tree/master/hellog3n)) that shows a blue torus and a button that when clicked makes the torus red:

```Go
package main

import (
	"github.com/g3n/engine/app"
	"github.com/g3n/engine/camera"
	"github.com/g3n/engine/core"
	"github.com/g3n/engine/geometry"
	"github.com/g3n/engine/gls"
	"github.com/g3n/engine/graphic"
	"github.com/g3n/engine/gui"
	"github.com/g3n/engine/light"
	"github.com/g3n/engine/material"
	"github.com/g3n/engine/math32"
	"github.com/g3n/engine/renderer"
	"github.com/g3n/engine/util/helper"
	"github.com/g3n/engine/window"
	"time"
)

func main() {

	// Create application and scene
	a := app.App()
	scene := core.NewNode()

	// Set the scene to be managed by the gui manager
	gui.Manager().Set(scene)

	// Create perspective camera
	cam := camera.New(1)
	cam.SetPosition(0, 0, 3)
	scene.Add(cam)

	// Set up orbit control for the camera
	camera.NewOrbitControl(cam)

	// Set up callback to update viewport and camera aspect ratio when the window is resized
	onResize := func(evname string, ev interface{}) {
		// Get framebuffer size and update viewport accordingly
		width, height := a.GetSize()
		a.Gls().Viewport(0, 0, int32(width), int32(height))
		// Update the camera's aspect ratio
		cam.SetAspect(float32(width) / float32(height))
	}
	a.Subscribe(window.OnWindowSize, onResize)
	onResize("", nil)

	// Create a blue torus and add it to the scene
	geom := geometry.NewTorus(1, .4, 12, 32, math32.Pi*2)
	mat := material.NewStandard(math32.NewColor("DarkBlue"))
	mesh := graphic.NewMesh(geom, mat)
	scene.Add(mesh)

	// Create and add a button to the scene
	btn := gui.NewButton("Make Red")
	btn.SetPosition(100, 40)
	btn.SetSize(40, 40)
	btn.Subscribe(gui.OnClick, func(name string, ev interface{}) {
		mat.SetColor(math32.NewColor("DarkRed"))
	})
	scene.Add(btn)

	// Create and add lights to the scene
	scene.Add(light.NewAmbient(&math32.Color{1.0, 1.0, 1.0}, 0.8))
	pointLight := light.NewPoint(&math32.Color{1, 1, 1}, 5.0)
	pointLight.SetPosition(1, 0, 2)
	scene.Add(pointLight)

	// Create and add an axis helper to the scene
	scene.Add(helper.NewAxes(0.5))

	// Set background color to gray
	a.Gls().ClearColor(0.5, 0.5, 0.5, 1.0)

	// Run the application
	a.Run(func(renderer *renderer.Renderer, deltaTime time.Duration) {
		a.Gls().Clear(gls.DEPTH_BUFFER_BIT | gls.STENCIL_BUFFER_BIT | gls.COLOR_BUFFER_BIT)
		renderer.Render(scene, cam)
	})
}
```


 <img style="float: right;" src="https://github.com/g3n/demos/blob/master/hellog3n/screenshot.png" alt="hellog3n Screenshot"/>
 
 
You can download and install `hellog3n` via:
 
 go install github.com/g3n/demos/hellog3n@latest

For more complex demos please see the [G3N demo program](https://github.com/g3n/g3nd).

## Documentation

The complete engine API reference can be found here: [![GoDoc](https://godoc.org/github.com/g3n/engine?status.svg)](https://godoc.org/github.com/g3n/engine).

There is also the beginning of a Getting Started Guide, and a newly created list of Guides and Tutorials:

* [Getting Started](https://github.com/g3n/engine/wiki/Getting-Started-(WIP))
* [Guides and Tutorials](https://github.com/g3n/engine/wiki/Guides-and-Tutorials)

Along with those, a good way to learn how to use the engine is to see the source code of [G3ND - the G3N demo](https://github.com/g3n/g3nd).
 
## Contributing

If you find a bug or create a new feature you are encouraged to send pull requests!

## Community

Join our [Discord channel](https://discord.gg/NfaeVr8zDg). It's the best way to have your questions answered quickly by the G3N community.

## Stargazers over time

[![Stargazers over time](https://starchart.cc/g3n/engine.svg)](https://starchart.cc/g3n/engine)

Go implementation of the A\* path finding algorithm.

go-astar

3D engine for the Go language, works on Windows and Linux ([Harfang on Go.dev](https://github.com/harfang3d/harfang-go)).

<img src="https://github.com/harfang3d/image-storage/raw/main/brand/logo_harfang3d_owl_only.png" align="right" width="200"/>

# HARFANG® 3D engine

[![PyPI](https://img.shields.io/pypi/v/harfang)](https://pypi.org/project/harfang)
[![Downloads](https://static.pepy.tech/badge/harfang)](https://pepy.tech/project/harfang)
[![Downloads](https://static.pepy.tech/badge/harfang/month)](https://pepy.tech/project/harfang)

HARFANG®3D is an all-in-one 3D visualization library usable in C++, Python, Lua and Go.
#### Table of contents

1. [About](#section_1)
 - [Features](#subsection_1a)
 - [Screenshots](#subsection_1b)
2. [Download](#section_2)
3. [Building the SDK](#section_3)
 - [Prerequisites](#subsection_3a)
 - [Building](#subsection_3b)
4. [Using the C++ SDK](#section_4)
5. [Version](#section_5)
6. [License](#section_6)
7. [Contribute](#section_7)
8. [Support Harfang](#section_8)

<a name="section_1"></a>
# About

HARFANG®3D is an easy-to-adapt, cross-platform, multi-language, powerful and optimized solution to integrate with embedded systems, into existing environments and combining features to meet the industrial standards of real-time 3D imaging.

The HARFANG®3D architecture makes it easy to meet the requirements for hardware integration, display performance and security.

HARFANG®3D is written in C++ and is based on the open-source bgfx library supporting Vulkan, Metal, DirectX (from 9 to 12), OpenGL and OpenGL ES. It Builds on Windows, Linux, Intel and ARM.

<a name="subsection_1a"></a>
## Features

Platforms supported
* Win32 and Win64 Intel
* Linux 64 Intel
* Aarch 64 ARM

Scene API
* Node & component based
* Performance oriented

Rendering pipeline
* Low-spec PBR rendering pipeline
* High-spec 'AAA' rendering pipeline (screen space GI & reflection)
* Support of user pipeline shaders

VR API
* XR support via OpenXR
* VR support via OpenVR/SteamVR including Eye tracking (SRanipal)
* Tested with the HTC Vive/Vive Pro, Valve Index, Lenovo Explorer, Oculus Rift S, Oculus Quest 2, Varjo XR-3

Physics API
* Rigid bodies, collisions, mechanical constraints, ray casting

Audio API
* Play/stream WAV/OGG formats
* 3D audio spatialization

Languages supported
* C++
* Python _(3.2+)_
* Lua _(5.4)_
* Go _(1+, experimental)_
<a name="subsection_1b"></a>
## Screenshots

The following screenshots were captured on a 1080GTX in 1080P running at 60FPS.

![alt text](https://raw.githubusercontent.com/harfang3d/image-storage/main/portfolio/2.0.111/sun_temple_aaa.png)

![alt text](https://raw.githubusercontent.com/harfang3d/image-storage/main/portfolio/2.0.111/sun_temple_aaa_2.png)

*(Sun Temple, courtesy of the Open Research Content Archive (ORCA))*

<a name="section_2"></a>
# Download

You can download the HARFANG binaries from the official website:
https://dev.harfang3d.com/releases

<a name="section_3"></a>
# Build the SDK

<a name="subsection_3a"></a>
## Prerequisites

* Git
* CMake 3.19+
* CPython 3.2+
* Go 1+ _(for Harfang Go module)_
* Doxygen _(for Harfang C++ SDK documentation)_
* Autodesk FBX SDK _(for FBX Converter)_

### Windows
* Visual Studio 2019 _(C++ compiler and IDE)_
* MinGW _(for Harfang Go module)_

### Linux
* GCC 9 or above
* CLang 

<a name="subsection_3b"></a>
## Building

1. Clone the `Harfang 3D` repository including its submodules.
 ```
 git clone --recursive -j8 https://github.com/harfang3d/harfang3d.git
 cd harfang3d
 ```

1. Create build directory. Note that the described directory layout is not mandatory.
 ```
 mkdir build
 cd build
 ``` 

1. Clone Fabgen.
 ```
 git clone https://github.com/ejulien/FABGen.git
 ```

1. Download and install Autodesk FBX SDK.

1. Create a directory that will hold the build system generated by CMake.
 ```
 mkdir cmake
 cd cmake
 ```

1. Generate the build system using CMake. For example, on Windows it will be:
 ```
 cmake ../.. -G "Visual Studio 16 2019" -A x64 \
 -DCMAKE_INSTALL_PREFIX:PATH="D:/harfang/build/install" \
 -DPYTHON_EXECUTABLE:FILEPATH="C:/Python36/python.exe" \
 -DHG_FABGEN_PATH:PATH="D:/harfang/build/fabgen" \
 -DHG_FBX_SDK:PATH="D:/fbx_sdk" 
 ``` 

 * `CMAKE_INSTALL_PREFIX` specifies the directory where the Harfang SDK will installed.
 * `PYTHON_EXECUTABLE` is the path the Python 3 interpreter.
 * `FABGEN_PATH` is the path to Fabgen binding generator.
 * `HG_FBX_SDK` is the path to Autodesk FBX SDK.

 &nbsp; 
 Here is the list of available CMake options.

 * __C++ SDK__
 * `HG_BUILD_CPP_SDK` : Build C++ SDK (default: __OFF__).
 * `HG_BUILD_TESTS` : Build C++ SDK unit tests (default: __OFF__).
 * `HG_BUILD_DOCS` : Build API and C++ SDK documentations (default: __OFF__).
 * `HG_ENABLE_BULLET3_SCENE_PHYSICS` : Enable Bullet physics API (default: __ON__).
 * `HG_ENABLE_RECAST_DETOUR_API` : Enable Recast/Detour navigation mesh and path finding API (default: __ON__).
 * `HG_ENABLE_OPENVR_API` : Enable OpenVR API (default: __OFF__).
 * `HG_ENABLE_SRANIPAL_API` : Enable VIVE Eye and Facial Tracking SDK (SRanipal) API (default: __OFF__).
 * __Tools__
 * `HG_BUILD_ASSETC` : Build AssetC asset compiler (default: __ON__).
 * `HG_BUILD_ASSIMP_CONVERTER` : Build Assimp based 3D model converter (default: __ON__).
 * `HG_BUILD_FBX_CONVERTER` : Build FBX converter (default: __ON__).
 * `HG_BUILD_GLTF_IMPORTER` : Build GLTF importer (default: __ON__).
 * `HG_BUILD_GLTF_EXPORTER` : Build GLTF exporter (default: __ON__).
 * __Bindings__
 * `HG_BUILD_HG_LUA` : Build Harfang LUA module (default: __OFF__).
 * `HG_BUILD_HG_PYTHON` : Build Harfang Python module (wheel) (default: __OFF__).
 * `HG_BUILD_HG_GO` : Build Harfang GO module (default: __OFF__).
 
 &nbsp; 

1. Build the SDK.
 ```
 cmake --build . --config Release --target INSTALL
 ```
 _Note: On Linux you will need to explicitly specify the build type with `-DCMAKE_BUILD_TYPE=Release`_ 

 Depending on the set of option passed to CMake the install directory will contain the following subdirectories:
 * `cppsdk` : Harfang C++ SDK.
 * `hg_python` : Harfang Python module.
 * `hg_lua` : Harfang LUA module.
 * `hg_go` : Harfang Go module.
 * `assetc` : Asset compiler.
 * `assimp_converter` : Assimp 3D model converter.
 * `fbx_converter` : FBX converter.
 * `gltf_importer` : GLTF importer.
 * `gltf_exporter` : GLTF exporter.
 
### Notes on Visual Studio Code

1. Install the CMakeTools extension.

1. Copy the `harfang/.vscode/template_settings.json` file to `harfang/.vscode/settings.json` and edit it to reflect your local installation.

1. Open the `harfang` folder in Visual Studio Code. CMakeTools should succesfully configure the project.

<a name="section_4"></a>
# Use the SDK

The Harfang C++ SDK directory `cppsdk` contains the following:
* `bin` : depending on the configuration used, this directory contains either a `Release` or `Debug` subdirectory with all the shared libraries.
* `lib` : like the `bin` directory, it contains a subdirectories named after the configuration used during build (`Release` or `Debug`) with all the generated static libraries.
* `include` : contains all the C++ include files of Harfang public API.
* `cmake` : contains the CMake configuration files. 

To add the Harfang C++ SDK to your CMake project, just add the following to the `CMakeLists.txt` file:
```cmake
find_package(harfang REQUIRED
 COMPONENTS cppsdk
 PATHS ${HG_CPPSDK_PATH}
 NO_DEFAULT_PATH
)
```
with `HG_CPPSDK_PATH` the path to the `cppsdk` directory. For example, if we follow the directory layout given above, it will be `D:/harfang/build/install/cppsdk`.

Targets should link against the following libraries.
* `hg::engine` 
* `hg::foundation` 
* `hg::platform`
* `hg::libluadll`

The `install_cppsdk_dependencies` function installs the Harfang C++ SDK shared libraries dependencies.
```cmake
install_cppsdk_dependencies(destination component)
```
* `destination` : is the library where the shared libraries will be installed.
* `component` : installation component name.

<a name="section_5"></a>
# Version

Harfang follows the Semantic Versioning Specification (SemVer) (http://semver.org).

Given a version number MAJOR.MINOR.PATCH, increment the:

* MAJOR version when you make incompatible API changes,
* MINOR version when you add functionality in a backwards-compatible manner, and
* PATCH version when you make backwards-compatible bug fixes.

<a name="section_6"></a>
# License

Harfang is licensed under the GPLv3, LGPLv3 and a commercial license: 
https://www.harfang3d.com/license

<a name="section_7"></a>
# Contribute
## Contributor License Agreement

By contributing your code to HARFANG you grant the [HARFANG3D organization](https://www.harfang3d.com/en_US/legal) a non-exclusive, irrevocable, worldwide, royalty-free, sublicenseable, transferable license under all of Your relevant intellectual property rights (including copyright, patent, and any other rights), to use, copy, prepare derivative works of, distribute and publicly perform and display the Contributions on any licensing terms, including without limitation:
(a) open source licenses like the MIT license; and (b) binary, proprietary, or commercial licenses. Except for the licenses granted herein, You reserve all right, title, and interest in and to the Contribution.

You confirm that you are able to grant us these rights. You represent that You are legally entitled to grant the above license. If Your employer has rights to intellectual property that You create, You represent that You have received permission to make the Contributions on behalf of that employer, or that Your employer has waived such rights for the Contributions.

You represent that the Contributions are Your original works of authorship, and to Your knowledge, no other person claims, or has the right to claim, any right in any invention or patent related to the Contributions. You also represent that You are not legally obligated, whether by entering into an agreement or otherwise, in any way that conflicts with the terms of this license.

The [HARFANG3D organization](https://www.harfang3d.com/en_US/legal) acknowledges that, except as explicitly described in this Agreement, any Contribution which you provide is on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING, WITHOUT LIMITATION, ANY WARRANTIES OR CONDITIONS OF TITLE, NON-INFRINGEMENT, MERCHANTABILITY, OR FITNESS FOR A PARTICULAR PURPOSE.

<a name="section_8"></a>
# How to support Harfang?

There are numerous ways to help Harfang grow its community:

* Give the repository a [Star :star:](https://github.com/harfang3d/harfang3d)
* Purchase a license of [Harfang Studio](https://www.harfang3d.com/en_US/studio)
* Subscribe to Harfang [Youtube channel](https://www.youtube.com/c/HARFANG3D/videos)
* Follow us on [Twitter](https://twitter.com/harfang3dengine/)
* Leave a Comment/Like on [Alternative To](https://alternativeto.net/software/harfang-3d/about/)

<a name="section_9"></a>
# More screenshots...

![Nvidia USD Attic](https://raw.githubusercontent.com/harfang3d/image-storage/main/portfolio/3.2.6/attic_harfang.png)

*(The NVIDIA USD Attic using the HARFANG 3D AAA renderer)*

![ORCA Sun Temple](https://raw.githubusercontent.com/harfang3d/image-storage/main/portfolio/3.1.1/sun_temple_aaa.png)

![ORCA Sun Temple](https://raw.githubusercontent.com/harfang3d/image-storage/main/portfolio/3.1.1/sun_temple_aaa_2.png)

*(Sun Temple, courtesy of the Open Research Content Archive (ORCA))*

![ORCA Bistro](https://raw.githubusercontent.com/harfang3d/image-storage/main/portfolio/3.1.1/cafe_exterior_aaa.png)

![ORCA Bistro](https://raw.githubusercontent.com/harfang3d/image-storage/main/portfolio/3.1.1/cafe_exterior_aaa_2.png)

*(Bistro, courtesy of the Open Research Content Archive (ORCA))*

![Sponza Atrium](https://raw.githubusercontent.com/harfang3d/image-storage/main/portfolio/3.1.1/sponza_atrium_aaa.png)

![Sponza Atrium](https://raw.githubusercontent.com/harfang3d/image-storage/main/portfolio/3.1.1/sponza_atrium_aaa_2.png)

*(Sponza Atrium GLTF, courtesy of Crytek/Themaister)*

![alt text](https://raw.githubusercontent.com/harfang3d/image-storage/main/portfolio/3.2.6/marine-melodies-screenshot_1280.png)

*(Marine Melodies, by Resistance Norway)*

Harfang3D

Leaf
====
A pragmatic game server framework in Go (golang).

Features
---------

* Extremely easy to use
* Reliable
* Multicore support
* Modularity

Community
---------



Documentation
---------

* [中文文档](https://github.com/name5566/leaf/blob/master/TUTORIAL_ZH.md)
* [English](https://github.com/name5566/leaf/blob/master/TUTORIAL_EN.md)

Licensing
---------

Leaf is licensed under the Apache License, Version 2.0. See [LICENSE](https://github.com/name5566/leaf/blob/master/LICENSE) for the full license text.


Leaf

Lightweight, facility, high performance golang based game server framework.

# Nano [![Build Status][1]][2] [![GoDoc][3]][4] [![Go Report Card][5]][6] [![MIT licensed][7]][8] 

[1]: https://github.com/lonng/nano/actions/workflows/go.yml/badge.svg?branch=master
[2]: https://github.com/lonng/nano/actions/workflows/go.yml
[3]: https://godoc.org/github.com/lonng/nano?status.svg
[4]: https://godoc.org/github.com/lonng/nano
[5]: https://goreportcard.com/badge/github.com/lonng/nano
[6]: https://goreportcard.com/report/github.com/lonng/nano
[7]: https://img.shields.io/badge/license-MIT-blue.svg
[8]: LICENSE

Nano is an easy to use, fast, lightweight game server networking library for Go.
It provides a core network architecture and a series of tools and libraries that
can help developers eliminate boring duplicate work for common underlying logic.
The goal of nano is to improve development efficiency by eliminating the need to
spend time on repetitious network related programming.

Nano was designed for server-side applications like real-time games, social games,
mobile games, etc of all sizes.

Join to Discord: [Nano Community](https://discord.gg/eHEDrBH5PV) 

## How to build a system with `Nano`

#### What does a `Nano` application look like?

The simplest "nano" application as shown in the following figure, you can make powerful applications by combining different components.

![Application](media/application.png)

In fact, the `nano` application is a collection of  [Component ](./docs/get_started.md#component) , and a component is a bundle of  [Handler](./docs/get_started.md#handler), once you register a component to nano, nano will register all methods that can be converted to `Handler` to nano service container. Service was accessed by `Component.Handler`, and the handler will be called while client request. The handler will receive two parameters while handling a message:
  - `*session.Session`: corresponding a client that apply this request or notify.
  - `*protocol.FooBar`: the payload of the request.

While you had processed your logic, you can response or push message to the client by `session.Response(payload)` and `session.Push('eventName', payload)`, or returns error when some unexpected data received.

#### How to build distributed system with `Nano`

Nano contains built-in distributed system solution, and make you creating a distributed game server easily.

See: [The distributed chat demo](https://github.com/lonng/nano/tree/master/examples/cluster)

The Nano will remain simple, but you can perform any operations in the component and get the desired goals. You can startup a group of `Nano` application as agent to dispatch message to backend servers.

#### How to execute the asynchronous task

```golang
func (manager *PlayerManager) Login(s *session.Session, msg *ReqPlayerLogin) error {
    var onDBResult = func(player *Player) {
        manager.players = append(manager.players, player)
        s.Push("PlayerSystem.LoginSuccess", &ResPlayerLogin)
    }
    
    // run slow task in new gorontine
    go func() {
        player, err := db.QueryPlayer(msg.PlayerId) // ignore error in demo
        // handle result in main logical gorontine
        nano.Invoke(func(){ onDBResult(player) })
    }
    return nil
}
```

## Documents

- English
    + [How to build your first nano application](./docs/get_started.md)
    + [Route compression](./docs/route_compression.md)
    + [Communication protocol](./docs/communication_protocol.md)
    + [Design patterns](./docs/design_patterns.md)
    + [API Reference(Server)](https://godoc.org/github.com/lonnng/nano)
    + [How to integrate `Lua` into `Nano` component(incomplete)](.)

- 简体中文
    + [如何构建你的第一个nano应用](./docs/get_started_zh_CN.md)
    + [路由压缩](./docs/route_compression_zh_CN.md)
    + [通信协议](./docs/communication_protocol_zh_CN.md)
    + [API参考(服务器)](https://godoc.org/github.com/lonnng/nano)
    + [如何将`lua`脚本集成到`nano`组件中(未完成)](.)

## Resources

- Javascript
  + [nano-websocket-client](https://github.com/lonnng/nano-websocket-client)
  + [nano-egret-client](https://github.com/lonnng/nano-egret-client)

- Typescript/cocos-creator
  + [nano-client-ts](https://github.com/adoontheway/nano-client-ts)

- Demo
  + [Implement a chat room in 100 lines with nano and WebSocket](./examples/demo/chat)
  + [Tadpole demo](./examples/demo/tadpole)
  + [四川麻将, 血战到底(三人模式/四人模式)完整项目实例](https://github.com/lonnng/nanoserver)

## Community

- QQGroup: [289680347](https://jq.qq.com/?_wv=1027&k=4EMMaha)
- Reddit: [nanolabs](https://www.reddit.com/r/nanolabs/)

## Successful cases

- [空来血战](https://fir.im/tios)

## Go version

`> go1.8`

## Installation

```bash
go get github.com/lonng/nano

# dependencies
go get -u github.com/pingcap/check
go get -u github.com/pingcap/errors
go get -u github.com/urfave/cli

go get -u google.golang.org/protobuf/proto
go get -u github.com/gorilla/websocket
go get -u google.golang.org/grpc
```

## Protocol Buffers
```bash
# protoc
# download form: https://github.com/protocolbuffers/protobuf/releases
# protoc-gen-go
go install google.golang.org/protobuf/cmd/protoc-gen-go@latest
go install google.golang.org/grpc/cmd/protoc-gen-go-grpc@latest
# delve
go install github.com/go-delve/delve/cmd/dlv@latest
```

## Test
```bash
go test -v ./...
```

## Benchmark

```bash
# Case:   PingPong
# OS:     Windows 10
# Device: i5-6500 3.2GHz 4 Core/1000-Concurrent   => IOPS 11W(Average)
# Other:  ...

cd ./benchmark/io
go test -v -tags "benchmark"
```

## License

[MIT License](./LICENSE)


nano

# Oak

## A Pure Go game engine

[![Go Reference](https://pkg.go.dev/badge/github.com/oakmound/oak/v4.svg)](https://pkg.go.dev/github.com/oakmound/oak/v4)
[![Code Coverage](https://codecov.io/gh/oakmound/oak/branch/master/graph/badge.svg)](https://codecov.io/gh/oakmound/oak)
[![Mentioned in Awesome Go](https://awesome.re/mentioned-badge-flat.svg)](https://github.com/avelino/awesome-go)

## Table of Contents

1. [Installation](#installation)

1. [Features](#features)

1. [Support](#support)

1. [Quick Start](#quick-start)

1. [Examples](#examples)

1. [Finished Games](#finished-games)

***

## Installation <a name="installation"/>

`go get -u github.com/oakmound/oak/v4`

## Features and Systems <a name="features"></a>

1. Window Management
 - Windows and key events forked from [shiny](https://pkg.go.dev/golang.org/x/exp/shiny)
 - Support for multiple windows running at the same time
1. [Image Rendering](https://pkg.go.dev/github.com/oakmound/oak/v4/render)
 - Manipulation
 - `render.Modifiable` interface
 - Integrated with optimized image manipulation via [gift](https://github.com/disintegration/gift)
 - Built in `Renderable` types covering common use cases
 - `Sprite`, `Sequence`, `Switch`, `Composite`
 - Primitive builders, `ColorBox`, `Line`, `Bezier`
 - History-tracking `Reverting`
 - Primarily 2D
1. [Particle System](https://pkg.go.dev/github.com/oakmound/oak/v4/render/particle)
1. [Mouse Handling](https://pkg.go.dev/github.com/oakmound/oak/v4/mouse)
1. [Joystick Support](https://pkg.go.dev/github.com/oakmound/oak/v4/joystick)
1. [Audio Support](https://pkg.go.dev/github.com/oakmound/oak/v4/audio)
1. [Collision](https://pkg.go.dev/github.com/oakmound/oak/v4/collision)
 - Collision R-Tree forked from [rtreego](https://github.com/dhconnelly/rtreego)
 - [2D Raycasting](https://pkg.go.dev/github.com/oakmound/oak/v4/collision/ray)
 - Collision Spaces
 - Attachable to Objects
 - Auto React to collisions through events
1. [2D Physics System](https://pkg.go.dev/github.com/oakmound/oak/v4/physics)
1. [Event Handler](https://pkg.go.dev/github.com/oakmound/oak/v4/event)

## Support <a name="support"></a>

For discussions not significant enough to be an Issue or PR, feel free to ping us in the #oak channel on the [gophers slack](https://invite.slack.golangbridge.org/). For insight into what is happening in oak see the [blog](https://200sc.dev/).

## Quick Start <a name="quick-start"></a>

This is an example of the most basic oak program:

```go
package main

import (
 "github.com/oakmound/oak/v4"
 "github.com/oakmound/oak/v4/scene"
)

func main() {
 oak.AddScene("firstScene", scene.Scene{
 Start: func(*scene.Context) {
 // ... draw entities, bind callbacks ... 
 }, 
 })
 oak.Init("firstScene")
}
```

See below or navigate to the [examples](examples) folder for demos. For more examples and documentation checkout [godoc](https://pkg.go.dev/github.com/oakmound/oak/v4) for reference documentation, the [wiki](https://github.com/oakmound/oak/wiki), or our extended features in [grove](https://github.com/oakmound/grove). 

## Examples <a name="examples"></a>

| | | |
|:-------------------------:|:-------------------------:|:-------------------------:|
|<img width="200" src="examples/platformer/example.gif" a=examples/platformer> [Platformer](examples/platformer) | <img width="200" src="examples/top-down-shooter//example.gif"> [Top down shooter](examples/top-down-shooter)|<img width="200" src="examples/flappy-bird//example.gif"> [Flappy Bird](examples/flappy-bird/)
| <img width="200" src="examples/bezier/example.PNG"> [Bezier Curves](examples/bezier) |<img width="200" src="examples/joystick-viz/example.gif"> [Joysticks](examples/joystick-viz)|<img width="200" src="examples/piano/example.gif"> [Piano](examples/piano)|
|<img width="200" src="examples/screenopts/example.PNG"> [Screen Options](examples/screenopts) | <img width="200" src="examples/multi-window/example.PNG"> [Multi Window](examples/multi-window) |<img width="200" src="examples/particle-demo/overviewExample.gif"> [Particles](examples/particle-demo)|

## Games using Oak <a name="finished-games"></a>

To kick off a larger game project you can get started with [game-template](https://github.com/oakmound/game-template).

| | |
|:-------------------------:|:-------------------------:|
|<img width="200" src="https://img.itch.zone/aW1hZ2UvMTk4MjIxLzkyNzUyOC5wbmc=/original/aRusLc.png" a=examples/platformer-tutorial> [Agent Blue](https://oakmound.itch.io/agent-blue) | <img width="200" src="https://img.itch.zone/aW1hZ2UvMTY4NDk1Lzc4MDk1Mi5wbmc=/original/hIjzFm.png"> [Fantastic Doctor](https://github.com/oakmound/lowrez17)
|<img width="200" src="https://img.itch.zone/aW1hZ2UvMzkwNjM5LzI2NzU0ODMucG5n/original/eaoFrd.png"> [Hiring Now: Looters](https://oakmound.itch.io/cheststacker) | <img width="200" src="https://img.itch.zone/aW1hZ2UvMTYzNjgyLzc1NDkxOS5wbmc=/original/%2BwvZ7j.png"> [Jeremy The Clam](https://github.com/200sc/jeremy)
|<img width="200" src="https://img.itch.zone/aW1hZ2UvOTE0MjYzLzUxNjg3NDEucG5n/original/5btfEr.png"> [Diamond Deck Championship](https://oakmound.itch.io/diamond-deck-championship) | <img width="200" src="https://img.itch.zone/aW1nLzgzMDM5MjcucG5n/105x83%23/oA19CL.png"> [SokoPic](https://oakmound.itch.io/sokopic) 

## On Pure Go <a name="pure-go"/>

Oak has recently brought in dependencies that include C code, but we still describe the engine as a Pure Go engine, which at face value seems contradictory. Oak's goal is that, by default, a user can pull down the engine and create a fully functional game or GUI application on a machine with no C compiler installed, so when we say Pure Go we mean that, by default, the library is configured so no C compilation is required, and that no major features are locked behind C compliation. 

We anticipate in the immediate future needing to introduce alternate drivers that include C dependencies for performance improvements in some scasenarios, and currently we have no OSX solution that lacks objective C code.

The Best Go Libraries For Game Development - Awesome game development libraries. (15)