Oak Nut engine.

Commonly called "onut". Game engine focused on rapid development. Aimed at Game Jams.

Quick javascript sample

Load image and draw a sprite

var texture = getTexture("image.png");

function render() {
    // Begin a batch
    SpriteBatch.begin();
    
    // Draw a sprite at screen coordinates x=200, y=100 from top left corner.
    SpriteBatch.drawSprite(texture, new Vector2(200, 100));
    
    // End and flush the batch
    SpriteBatch.end();
}

Update loop

function update(dt) {
    spriteAngle += dt * 45; // Will rotate 45 degree per second
}

function render() {
    ...
    
    // Draw a sprite at with an animated angle
    SpriteBatch.drawSprite(texture, new Vector2(200, 100), Color.WHITE, spriteAngle);
    
    ...
}

See onut/samplesJS/ folders for more detailed samples.

Overview

List of projects using it:

Global Game Jam 2020 - Arctic Distress

Global Game Jam 2020 - Click to Repair

Global Game Jam 2019 - Eagle's Nest

Global Game Jam 2018 - Messenger Hacker

Ottawa Game Jam 2017 - Sheep Dog Heroes
Linux Game Jam 2017 - Retro Game War

Ottawa Game Jam 2016 - Spy Satellite Showdown

Global Game Jam 2016 - Fire Whisperers

Ottawa Game Jam 2015 - Cannon Fodder Commander

Release history

Onut 4.0 - The 3D release - TBD
Onut 3.0 - The JavaScript release - Jul 14, 2017
Onut 2.0 - The Cleanup release - Apr 3, 2016
Onut 1.0 - Feb 6, 2016

JavaScript Game

Compile the executable

Clone onut somewhere on your PC.
Generate using cmake.
Build the JSStandAlone project in release.
Copy the executable to your game's folder.

Setting up your JavaScript project

Recommended to use Visual Studio Code.

Create a folder for your game somehere on your PC
Copy [onut path]/jsconfig.json, [onut path]/typings/onut.d.ts to YourGame path.
Create a settings.txt file. Refer to samples to see what can be put in there.
Create assets and javascript files
main.js will always be the last JavaScript file executed, use it to initialize stuff.

main.js

function update(dt) {
    // Update your game here
}

function render() {
}

C++ game

Recommended folder structure

Before you start. Please take note of the following folder structure. It is highly recommended for minimal setup time. The default asset search paths are configured for this structure. But it easy to add more using oContentManager->addSearchPath.

YourGame\
- assets\ Put game assets in here
  - ...
- src\ Your game source code (.h and .cpp)
- .. projects files or your CMakeLists.txt

main.cpp

Make sure to define those 6 functions. Otherwise you will get unresolved errors.

void initSettings()
{
    // Set Default game settings can be set using oSettings.
}

void init()
{
    // Load your content.
}

void shutdown()
{
    // Cleanup.
}

void update()
{
    // Game logic.
}

void render()
{
    // Game render.
}

void postRender()
{
    // Render more stuff after post process.
}

void renderUI()
{
    // Draw imgui debug UI.
}

Look at samples to see what can be done here.

Specific usages

SpriteAnim

Sprite anims can be edited in Aseprite and exported as json. Certain flags can be set on frame's properties. Properties are colon ":" separated.

i.e.: "loop:genfliph:next=idle"

Frame properties and their meaning:

name	usage	scope	meaning
loop	`loop`	tag	animation will be looped
genfliph	`genfliph`	tag	an extra animation will be created with the name tag+"_fliph", flipped horitontally
genflipv	`genflipv`	tag	an extra animation will be created with the name tag+"_fliph", flipped vertically
next	`next=tagName`	tag	when this animation is finished, it will trigger tagName
origin	`origin=x,y`	frame	set frame origin. This will apply to subsequent frames until the next origin.
sound	`sound=step.wav`	frame	plays a sound on this frame
soundcue	`soundcue=step.cue`	frame	plays a sound cue on this frame
vol	`vol=0.5`	frame	set volume for sound [0, 1].
pan	`pan=0.0`	frame	set panning for sound [-1, 1].
pitch	`pitch=2.0`	frame	set pitch for sound.
tags	`tags=tag1,tag2`	frame	Custom tags on this frame

When exporting the sprite sheet in json format, make sure to change "Hash" to "Array".

Mentions

Logo design by Pixilabs Software Inc.

Daivuk/onut