File manipulation with ImageSharp

gistfile1.txt

import the following nuget package:

> Install-Package SixLabors.ImageSharp.Drawing -Version 1.0.0-beta11

program.cs

using SixLabors.ImageSharp;
using SixLabors.ImageSharp.Drawing;
using SixLabors.ImageSharp.Drawing.Processing;
using SixLabors.ImageSharp.PixelFormats;
using SixLabors.ImageSharp.Processing;

static void Main(string[] args)
{
    var rand = new Random();

    var iterations = 5000;

    var destWidth = 4096;
    var destHeight = 4096;
    var shapeReductionFactor = 0.002f;
    var startingAlphaTransparency = 0.1f;
    var alphaTransparancyIncreaseStep = 0.06f;
    var StrokeInversionThreshold = 0.05;
    var polyMinSides = 4;
    var polyMaxSides = 10;
    var initialShapeSize = 0.75 * destHeight;

    using var source = Image.Load<Rgba32>("source3.jpg");

    var sourceWidth = source.Size().Width;
    var sourceHeight = source.Size().Height;

    using var image = new Image<Rgba32>(destWidth, destHeight);

    image.Mutate(ic =>
    {
        ic.Fill(Color.Black);

        var alpha = startingAlphaTransparency;
        var strokeSize = initialShapeSize;

        for(var i = 0; i < iterations; i++)
        {
            var srcX = rand.Next(0, sourceWidth);
            var srcY = rand.Next(0, sourceHeight);
            var srcRgb = source[srcX, srcY].Rgb;

            var destRgba = new Rgba32(srcRgb.R, srcRgb.G, srcRgb.B, (byte)alpha);
            var edges = rand.Next(polyMinSides, polyMaxSides);
            var x = rand.NextDouble() * destWidth;
            var y = rand.NextDouble() * destHeight;

            var rotation = (float)(90 * rand.NextDouble());
            var polygon = new RegularPolygon((float)x, (float)y, edges, (float)strokeSize, rotation);

            var color = destRgba.ToHex();
            Console.WriteLine($"{i}: {srcX} {srcY} {srcRgb} {destRgba}");
            ic.Fill(destRgba, polygon);

            if(false && strokeSize <= StrokeInversionThreshold * initialShapeSize)
            {
                var outliner = Outliner.GenerateOutline(polygon, 1);
                if ((srcRgb.R + srcRgb.G + srcRgb.B) / 3 < 128)
                {
                    ic.Fill(new Rgba32(255, 255, 255, alpha), outliner);
                }
                else
                { 
                    ic.Fill(new Rgba32(0, 0, 0, alpha), outliner);
                 }
            }

            strokeSize -= (shapeReductionFactor * strokeSize);
            alpha += alphaTransparancyIncreaseStep;
        }

    });

    using var outputStream = File.OpenWrite("out.png");
    image.SaveAsPng(outputStream);
    Console.WriteLine("Done!");
}