gosge

README

gosge

Go Simple Game Engine using an ECS

Info

gosge is an opinionated 2D only game engine the uses GOECS for easily develop games with an ECS paradigm.

Internally uses the go port of raylib for most of the device functionalities, including rendering.

Simple Hello World

package main

import (
	"github.com/juan-medina/goecs/pkg/entity"
	"github.com/juan-medina/gosge/pkg/components/color"
	"github.com/juan-medina/gosge/pkg/components/geometry"
	"github.com/juan-medina/gosge/pkg/components/text"
	"github.com/juan-medina/gosge/pkg/engine"
	"github.com/juan-medina/gosge/pkg/game"
	"github.com/juan-medina/gosge/pkg/options"
	"log"
)

// game options
var opt = options.Options{
	Title:      "Hello Game",
	BackGround: color.Black,
}
const (
	fontName  = "resources/go_regular.fnt"
	fontSize  = 100
)

var (
	// designResolution is how our game is designed
	designResolution = geometry.Size{Width: 1920, Height: 1080}
)

func main() {
	if err := game.Run(opt, loadGame); err != nil {
		log.Fatalf("error running the game: %v", err)
	}
}

func loadGame(eng engine.Engine) error {
	// Preload font
	if err := eng.LoadFont(fontName); err != nil {
		return err
	}

	// get the ECS world
	wld := eng.World()

	// gameScale from the real screen size to our design resolution
	gameScale := eng.GetScreenSize().CalculateScale(designResolution)

	// add the centered text
	wld.Add(entity.New(
		text.Text{
			String:     "Hello World",
			HAlignment: text.CenterHAlignment,
			VAlignment: text.MiddleVAlignment,
			Font:       fontName,
			Size:       fontSize * gameScale.Min,
		},
		geometry.Point{
			X: designResolution.Width / 2 * gameScale.Point.X,
			Y: designResolution.Height / 2 * gameScale.Point.Y,
		},
		color.White,
	))
	return nil
}

Run examples

The examples are available on this folder, or can be run using make:

$ make run example=hello
$ make run example=eyes
$ make run example=layers
$ make run example=stages
$ make run example=animation

Alternatively you could run them with :

$ go run examples/hello/hello.go
$ go run examples/eyes/eyes.go
$ go run examples/layers/layers.go
$ go run examples/stages/stages.go
$ go run examples/animation/animation.go

Requirements

Ubuntu

X11

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

Wayland

apt-get install libgl1-mesa-dev libwayland-dev libxkbcommon-dev

Fedora

X11

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

Wayland

dnf install mesa-libGL-devel wayland-devel libxkbcommon-devel

macOS

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

Windows

On Windows, you need C compiler, like Mingw-w64 or TDM-GCC. You can also build binary in MSYS2 shell.

Installation

go get -v -u github.com/juan-medina/gosge

Build Tags

• opengl21 : uses OpenGL 2.1 backend (default is 3.3)
• wayland : builds against Wayland libraries

Examples Resources

• Gopher Graphics
  • https://awesomeopensource.com/project/egonelbre/gophers
• Game art 2D:
  • https://www.gameart2d.com
• Mobile Game Graphics
  • https://mobilegamegraphics.com/product/free-parallax-backgrounds