/**
 * file: Htree.kt
 * date: 2019-06-23
 *
 * @author: SS
 *
 * Starting from n = 1, this program loops forever displaying
 * the level-n Htree, waits for the user to hit any key, then
 * displays the level-((n+1)%14) Htree, and waits for a key hit
 * by the user, and so on, ad infinitum.
 */

import processing.core.PApplet

fun main(args: Array<String>) {
    PApplet.main("HtreeSketch");
}

class HtreeSketch : PApplet() {
    var level = 0

    override fun settings() {
        //size(640, 640)
        fullScreen()
        noLoop()
    }

    override fun draw() {
        background(250)
        vsplit(width / 2F, height / 2F, width.toFloat(), height.toFloat(), ++level)
        level %= 14
    }

    override fun keyPressed() {
        redraw()
    }

    fun vsplit(x: Float, y: Float, w: Float, h: Float, n: Int) {
        if (n < 1) return
        val x0 = x - w / 4F
        val x1 = x + w / 4F
        line(x0, y, x1, y)
        hsplit(x0, y, w / 2F, h, n - 1)
        hsplit(x1, y, w / 2F, h, n - 1)
    }

    fun hsplit(x: Float, y: Float, w: Float, h: Float, n: Int) {
        if (n < 1) return
        val y0 = y - h / 4F
        val y1 = y + h / 4F
        line(x, y0, x, y1)
        vsplit(x, y0, w, h / 2F, n - 1)
        vsplit(x, y1, w, h / 2F, n - 1)
    }
}