Koto

Koto is some random garbage th clone

--Koto main developer, Zzzyt

Koto (KOtlin TOuhou Engine) is a Kotlin Touhou-style bullet hell game engine/template using Libgdx. The goal of the project is to provide a simple and easy-to-use framework for creating Touhou-style games in Kotlin.

Why Koto?

There are many Touhou-style game engines and other general game engines out there. It is easy to prototype a game using Unity, Godot or Danmakufu. However, we would like to prove that Kotlin is also a great choice for Touhou game development. And here is Koto, built by Kotlin lovers, for Kotlin lovers.

Koto is:

• Performant: 10k+ bullets at 60fps by utilizing low-level rendering and efficient data structures.
• Intuitive: Instead of giving developers a onFrame method called every frame, Koto uses coroutines and Kotlin DSLs to create intuitive sequential patterns.
• Kotlin-style: Koto makes use of many Kotlin features such as extension functions, higher-order functions, and DSLs to provide quicker development experience.
• Out-of-the-box: Koto provides many commonly-used built-in features (see below) and tons of helper functions. Less boilerplate, more creativity.
• Authentic: Koto aims to replicate every detail of Touhou games, from effects to scoring systems.

Here is an example of how you write a spell card in Koto:

override fun spell(): Task = CoroutineTask {
    val boss = getBoss()

    //Create spellcard cutin effect
    game.stage.addDrawable(Cutin(getRegion("portrait/aya/attack.png")))
    repeat(20) {
        wander(boss, 120) //wander for 120 frames. Touhou bosses love to do this.
        cast(boss.x, boss.y) //cast effect
        wait(90)

        cast2(boss.x, boss.y) //another cast effect
        wait(30)

        boss.usingAction = true //use action animation instead of idle
        repeat(3) {
            ring( //creating patterns is simple!
                "DS_BALL_M_A_BLUE", //asset name
                boss.x,
                boss.y,
                50f, //radius
                difficultySelect(8, 12, 16, 20), //number of bullets, easily scaled by difficulty
                startAngle = random(0f, 360f), //angle
                speed = 5f, //speed
            )
            wait(20)
        }
        boss.usingAction = false
        wait(30)
    }
}

Features

• UI
  • Grid System for faster UI positioning
  • Screen management for smooth transitions
  • Built-in containers
  • Smart HD font rendering
  • HSV support
• STG
  • Points, grazing, lives, bombs, power, etc.
  • Complete replay system
  • History data/scoreboard system
  • Laser and curvy laser support
  • Complete boss and spell card support (including card history)
  • Background and parallax support
  • Pause system
  • Dialog system
  • Default shotsheet for prototyping
  • All kinds of animation (spell declaration, boss cast, health circle, etc.)
• High-level System
  • Stage/Spell practise
  • Extra stage
  • Music room
  • Options
  • I18N