system.drawing to skiasharp

createpolygon.cs

public string DrawRegularPolygonSK(int vertexCount, float radius, SocketCommandContext context, [Optional] int rndNum)
{
    string imagesPath = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "data", "images");
    if (!Directory.Exists(imagesPath))
        Directory.CreateDirectory(imagesPath);

    using (SKBitmap bmp       = new SKBitmap(1024, 1024))
    using (SKPaint outerPaint = new SKPaint())
    using (SKPaint innerPaint = new SKPaint())
    using (SKPaint textPaint  = new SKPaint())
    using (SKCanvas canvas    = new SKCanvas(bmp))
    {
        SKPoint center = new SKPoint(bmp.Width / 2, bmp.Height / 2);
        var angle = Math.PI * 2 / vertexCount;
        var points = Enumerable.Range(0, vertexCount).Select(i => SKPoint.Add(center, new SKSize((float)Math.Sin(i * angle) * radius,
            (float)Math.Cos(i * angle) * radius)));
        var color = GetGuildUserRoleColor(context.User as SocketGuildUser).Result;
        
        canvas.Clear();

        // this is for the filling of the polygon.
        innerPaint.Color = new SKColor(color.R, color.G, color.B);
        innerPaint.Style = SKPaintStyle.Fill;
        innerPaint.StrokeWidth = 5f;
        SKPath innerPath = new SKPath();
        foreach (var point in points)
        {
            if (point == points.First())
                innerPath.MoveTo(point);
            else
                innerPath.LineTo(point);
        }
        innerPath.Close();
        canvas.DrawPath(innerPath, innerPaint);

        // this is for the lines of the polygon.
        outerPaint.Color = SKColors.Black;
        outerPaint.StrokeWidth = 10f;
        outerPaint.StrokeCap = SKStrokeCap.Round;
        outerPaint.Style = SKPaintStyle.Stroke;
        SKPath outerPath = new SKPath();
        foreach (var point in points)
        {
            if (point == points.First())
                outerPath.MoveTo(point);
            else
                outerPath.LineTo(point);
        }
        outerPath.Close();
        canvas.DrawPath(outerPath, outerPaint);

        // this is for the text.
        textPaint.TextSize = 240f;
        textPaint.IsAntialias = true;

        if (color.R * 0.299f + color.G * 0.587f + color.B * 0.114f > 150) // decides the color of text based on bg color
            textPaint.Color = SKColors.Black;
        else
            textPaint.Color = SKColors.White;

        textPaint.Style = SKPaintStyle.StrokeAndFill;
        textPaint.StrokeWidth = 15f;
        textPaint.TextAlign = SKTextAlign.Center;
        textPaint.GetFontMetrics(out var skFontMetrics);
        canvas.DrawText(rndNum.ToString(), center.X, center.Y + skFontMetrics.CapHeight / 2, textPaint); // text's height is 188 pixels at size 240f and stroke 15f

        using (var stream = File.Create(Path.Combine(imagesPath, context.Message.Id.ToString() + ".png")))
        {
            SKData data = SKImage.FromBitmap(bmp).Encode(SKEncodedImageFormat.Png, 100);
            data.SaveTo(stream);
        }

        return Path.Combine(imagesPath, context.Message.Id.ToString() + ".png").ToString();
    }
}