G3N - Go 3D Game Engine
G3N (pronounced "gen") is a cross-platform OpenGL 3D game engine written in Go.
### **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.**
## Highlighted Projects
[Gokoban - 3D Puzzle Game (_1st place in the 2017 Gopher Game Jam_)](https://github.com/danaugrs/gokoban)
## Dependencies
**G3N requires Go 1.8+**
The engine requires an OpenGL driver and a GCC-compatible C compiler to be installed.
On Unix-based systems the engine depends on some C libraries that can be installed using the appropriate distribution package manager.
* For Ubuntu/Debian-like Linux distributions, install the following packages:
* `xorg-dev`
* `libgl1-mesa-dev`
* `libopenal1`
* `libopenal-dev`
* `libvorbis0a`
* `libvorbis-dev`
* `libvorbisfile3`
* For Fedora, install the required packages:
```
$ 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
```
* For CentOS 7, enable the EPEL repo then install the same packages as for Fedora above:
```
$ sudo yum -y install https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm
```
Remember to use `yum` instead of `dnf` for the package installation command.
* For Windows, the necessary audio libraries sources and DLLs are supplied but they need to be installed
manually. Please see [Audio libraries for Windows](audio/windows) for details.
We tested the Windows build using the [mingw-w64](https://mingw-w64.org) toolchain.
* For macOS, you should install the development files of OpenAL and Vorbis. If
you are using [Homebrew](https://brew.sh/) as your package manager, run:
`brew install libvorbis openal-soft`
## Installation
The following command will download the engine along with all its Go dependencies:
`go get -u github.com/g3n/engine/...`
## Features
* Cross-platform: Windows, Linux, and macOS
* 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 ortographic 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
## 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.
You can download and install `hellog3n` via: `go get -u github.com/g3n/demos/hellog3n`
For more complex demos please see the [G3N demo program](https://github.com/g3n/g3nd).
```Go
package main
import (
"github.com/g3n/engine/util/application"
"github.com/g3n/engine/geometry"
"github.com/g3n/engine/material"
"github.com/g3n/engine/math32"
"github.com/g3n/engine/graphic"
"github.com/g3n/engine/light"
)
func main() {
app, _ := application.Create(application.Options{
Title: "Hello G3N",
Width: 800,
Height: 600,
})
// Create a blue torus and add it to the scene
geom := geometry.NewTorus(1, .4, 12, 32, math32.Pi*2)
mat := material.NewPhong(math32.NewColor("DarkBlue"))
torusMesh := graphic.NewMesh(geom, mat)
app.Scene().Add(torusMesh)
// Add lights to the scene
ambientLight := light.NewAmbient(&math32.Color{1.0, 1.0, 1.0}, 0.8)
app.Scene().Add(ambientLight)
pointLight := light.NewPoint(&math32.Color{1, 1, 1}, 5.0)
pointLight.SetPosition(1, 0, 2)
app.Scene().Add(pointLight)
// Add an axis helper to the scene
axis := graphic.NewAxisHelper(0.5)
app.Scene().Add(axis)
app.CameraPersp().SetPosition(0, 0, 3)
app.Run()
}
```
## Documentation
For the engine API reference, please see
[](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:
* https://github.com/g3n/engine/wiki/Getting-Started-(WIP)
* https://github.com/g3n/engine/wiki/Guides-and-Tutorials
Along with those, a good way to learn G3N is to step through the source code of the
[demos](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 [channel](https://gophers.slack.com/messages/g3n) on Gophers Slack ([Click here to register for Gophers Slack](https://invite.slack.golangbridge.org/)). It's a great way to have your questions answered quickly by the G3N community.