一顆心到一個圓的演變，javafx框架tornadofx動畫演示

import javafx.animation.AnimationTimer
import javafx.application.Application
import javafx.application.Platform
import javafx.geometry.Pos
import javafx.scene.canvas.GraphicsContext
import javafx.scene.control.RadioButton
import javafx.scene.paint.Color
import tornadofx.*
import java.util.*
import kotlin.math.PI
import kotlin.math.cos
import kotlin.math.sin

fun main(args: Array<String>) {
    Application.launch(TestApp::class.java, *args)
}

class TestApp : App(TestView::class)
class TestView : View("一顆心到一個圓的演變") {
    val isRun = booleanProperty()
    val pNums = intProperty()
    val aniMate = AniTimer()
    var t = -PI
    var renderedList: MutableList<Point> = LinkedList<Point>()
    val iip = intProperty(2)
    val step = doubleProperty(0.1)
    lateinit var context: GraphicsContext
    override val root = borderpane {

        top = vbox(10) {
            style {
                alignment = Pos.CENTER
            }
            hbox(10) {
                label("點密度：")
                togglegroup {
                    listOf(0.01, 0.03, 0.05, 0.07, 0.1).map { v ->
                        radiobutton(v.toString(), this, v) { if (v === 0.1) isSelected = true }
                    }
                    selectedToggleProperty().addListener { _, _, newValue ->
                        step.value = (newValue as RadioButton).text.toDouble()
                        runn()
                    }
                }
            }
            hbox(10) {
                label("花瓣數：")
                togglegroup {
                    val tg=this
                    vbox(10) {
                        hbox(10) {
                            listOf(2, 3, 4, 5,6,7,8,9,10,11).map { v ->
                                radiobutton(v.toString(), tg, v) { if (v === 2) isSelected = true }
                            }
                        }
                        hbox(10) {
                            listOf(12,13,14,15,16,17,18,19,20).map { v ->
                                radiobutton(v.toString(), tg, v)
                            }
                        }
                        hbox(10) {
                            listOf(21,22,23,24,25,26,27,28,150).map { v ->
                                radiobutton(v.toString(), tg, v)
                            }
                        }
                    }
                    selectedToggleProperty().addListener { _, _, newValue ->
                        iip.value = (newValue as RadioButton).text.toInt()
                        runn()
                    }
                }
                button("start") {
                    isRun.addListener { _, _, isrun ->
                        if (isrun)
                            this.text = "Pause"
                        else
                            this.text = "Start"
                    }
                    action {
                        runn()
                    }
                }
                label(pNums.stringBinding { "當前點數：$it" })
            }
        }

        center = canvas(700.0, 550.0) {
            style {
                alignment = Pos.CENTER
            }
            context = this.graphicsContext2D
            paddingAll = 30
        }
    }

    fun runn(){
        if (isRun.value) {
            aniMate.stop()
            isRun.value = false
        } else {
            t = -PI
            renderedList.clear()
            pNums.value = 0
            aniMate.start()
            isRun.value = true
        }
    }
    inner class AniTimer : AnimationTimer() {
        var lastTime = 0L
        val r = 10.0
        var syncLock = Any()
//        var ii = iip.value
        override fun handle(now: Long) {
            if ((now - lastTime) > 10000000) {
                lastTime = now
            } else {
                return
            }
            Platform.runLater {
                val y = 250 + (iip.value * cos(t) - cos(iip.value * t)) * -200/iip.value
                val x = 300 + (iip.value * sin(t) - sin(iip.value * t)) * 200/iip.value
                val p = Point(x, y)
                // 鎖住，防止其餘線程修改
                synchronized(syncLock) {
                    // 添加歷史記錄
                    renderedList.add(p)
                    // 清屏
                    context.fill = Color.WHITE
                    context.clearRect(0.0, 0.0, 1000.0, 700.0)
                    context.fill = Color.RED
                    // 渲染點
                    for (point in renderedList) {
                        context.fillOval(point.x, point.y, r, r)

                    }
                    pNums.value += 1
                    t += step.value
                    // 控制點的數量
                    if (t > PI) {
                        aniMate.stop()
                        isRun.value = false
                    }
                }
            }
        }
    }
}

class Point(val x: Double, val y: Double)