Kotlin Advent Calender - Game

MyGame.kt

package org.veiset.game

import com.badlogic.gdx.Gdx
import com.badlogic.gdx.Input
import com.badlogic.gdx.backends.lwjgl.LwjglApplication
import com.badlogic.gdx.backends.lwjgl.LwjglApplicationConfiguration
import com.badlogic.gdx.graphics.Color
import com.badlogic.gdx.graphics.glutils.ShapeRenderer
import ktx.app.KtxApplicationAdapter
import ktx.app.clearScreen
import ktx.graphics.use

fun main() {
    val config = LwjglApplicationConfiguration().apply {
        width = 1280
        height = 720
    }
    LwjglApplication(MyGame(), config)
}

data class Santa(val position: Float)
data class ChristmasGift(
    var height: Float = 720f,
    val position: Float = (40..1200).random().toFloat()
)

class MyGame : KtxApplicationAdapter {
    private lateinit var renderer: ShapeRenderer

    private var player = Santa(40f)
    private var gifts = emptyList<ChristmasGift>()

    override fun create() {
        renderer = ShapeRenderer()
    }

    override fun render() {
        handleInput()
        logic()
        draw()
    }

    private fun handleInput() {
        if (Gdx.input.isKeyPressed(Input.Keys.A)) {
            player = Santa(player.position - 5f)
        } else if (Gdx.input.isKeyPressed(Input.Keys.D)) {
            player = Santa(player.position + 5f)
        }
    }

    private fun logic() {
        if (Math.random() > 0.95) {
            gifts = gifts + ChristmasGift()
        }
        gifts.forEach {
            it.height -= 1f
        }
    }

    private fun draw() {
        clearScreen(0f, 0f, 0f, 0f)

        renderer.use(ShapeRenderer.ShapeType.Filled) {
            renderer.color = Color.GREEN
            gifts.forEach {
                renderer.rect(it.position, it.height, 60f, 60f)
            }
        }

        renderer.use(ShapeRenderer.ShapeType.Filled) {
            renderer.color = Color.RED
            renderer.rect(player.position, 80f, 80f, 80f)
        }
    }
}