一颗心到一个圆的演变，javafx框架tornadofx动画演示

import javafx.geometry.Pos
import javafx.scene.canvas.GraphicsContext
import javafx.scene.control.RadioButton
import javafx.scene.paint.Color
import javafx.scene.text.FontWeight
import tornadofx.*
import java.util.*
import kotlin.math.PI
import kotlin.math.cos
import kotlin.math.sin


class TestApp : App(TestView::class)
class TestView : View("一颗心到一个圆的演变") {
    val isRun = booleanProperty()
    var t = -PI
    val r = 10.0
    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 { borderColor += box(Color.TRANSPARENT, Color.TRANSPARENT, Color.LIGHTGREY, Color.TRANSPARENT) }
            alignment = Pos.CENTER
            hbox(10) {
                label("点密度：")
                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("花瓣数：")
                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()
                    }
                }
            }
        }

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

    fun runn() {
        // 清屏
        t=-PI
        var i=0
        context.clearRect(0.0, 0.0, 1000.0, 700.0)
        runAsync {
            while (t < PI) {
                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)
                renderedList.add(p)
                with(context) {
                    fill = Color.RED
                    fillOval(p.x, p.y, r, r)
                    t += step.value
                    i++
                    updateTitle(i.toString())
                    Thread.sleep(10)
                }
            }
        }
    }
}
class StatusView : View() {
    val status: TaskStatus by inject()
    override val root = vbox(4) {
        style { borderColor += box(Color.LIGHTGREY, Color.TRANSPARENT, Color.TRANSPARENT, Color.TRANSPARENT) }
        label(status.title.stringBinding { "点数：$it" }).style { fontWeight = FontWeight.BOLD }
    }
}

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