triangle spiral

TriangleSpiral.kt

package org.ygl.openrndr.demos

import org.openrndr.application
import org.openrndr.color.ColorRGBa
import org.openrndr.color.rgb
import org.openrndr.draw.LineCap
import org.openrndr.draw.LineJoin
import org.openrndr.extra.compositor.compose
import org.openrndr.extra.compositor.draw
import org.openrndr.extra.compositor.post
import org.openrndr.extra.fx.antialias.FXAA
import org.openrndr.extra.shapes.regularPolygonRounded
import org.openrndr.ffmpeg.ScreenRecorder
import org.openrndr.math.Vector2
import org.openrndr.math.transforms.transform
import org.openrndr.shape.ShapeContour
import org.openrndr.shape.compound
import org.openrndr.shape.contour
import org.ygl.openrndr.demos.util.GlamourBlur
import kotlin.math.PI
import kotlin.math.sin

private const val WIDTH = 920
private const val HEIGHT = 920
private const val TOTAL_FRAMES = 360
private const val RECORDING = true

fun main() = application {

    configure {
        width = WIDTH
        height = HEIGHT
    }

    program {

        var time = 0.0
        val bgColor = rgb("EDE8C1")
        val fgColor = rgb("2e294e")

        val numPoints = 8000
        val shape = regularPolygonRounded(3, radius = 20.0)
        val points = MutableList(numPoints) { Vector2.ZERO }
        val turns = 60

        fun computePath() {
            for (i in 0 until numPoints) {
                val pct = i / (numPoints - 0.0)
                val position = (time + turns * pct) % 1.0
                points[i] = shape.position(position).rotate(15 * sin(2 * PI * (pct + time))) * (pct * 80)
            }
        }

        val frame = compound {
            difference {
                shape(drawer.bounds.moved(-drawer.bounds.center).shape)
                shape(drawer.bounds.moved(-drawer.bounds.center).offsetEdges(-50.0).shape)
            }
        }

        val composite = compose {
            draw {
                drawer.clear(bgColor)

                drawer.lineCap = LineCap.ROUND
                drawer.lineJoin = LineJoin.ROUND

                drawer.stroke = fgColor//.opacify(0.8)
                drawer.strokeWeight = 6.0
                drawer.contour(ShapeContour.fromPoints(points, false))

                drawer.stroke = fgColor
                drawer.fill = bgColor
                drawer.shapes(frame)
            }
        }


        if (RECORDING) {
            extend(ScreenRecorder()) {
                outputFile = "video/TriangleSpiral.mp4"
                frameRate = 60
                frameClock = true
            }
        }

        extend {
            drawer.translate(drawer.bounds.center)

            time = ((frameCount - 1)  % TOTAL_FRAMES) / TOTAL_FRAMES.toDouble()

            computePath()

            composite.draw(drawer)

            if (RECORDING) {
                if (frameCount >= TOTAL_FRAMES) {
                    application.exit()
                }
            }
        }
    }
}