SolidPen.cs

using System.Threading.Tasks;
using System.Xml;
using SkiaSharp;
using Waher.Layout.Layout2D.Model.Attributes;
 
namespace Waher.Layout.Layout2D.Model.Pens
{
    public class SolidPen : Pen 
    {
        private ColorAttribute color;
 
        public SolidPen(Layout2DDocument Document, ILayoutElement Parent)
            : base(Document, Parent)
        {
        }
 
        public override string LocalName => "SolidPen";
 
        public ColorAttribute ColorAttribute
        {
            get => this.color;
            set => this.color = value;
        }
 
        public override Task FromXml(XmlElement Input)
        {
            this.color = new ColorAttribute(Input, "color", this.Document);
            return base.FromXml(Input);
        }
 
        public override void ExportAttributes(XmlWriter Output)
        {
            base.ExportAttributes(Output);
 
            this.color?.Export(Output);
        }
 
        public override ILayoutElement Create(Layout2DDocument Document, ILayoutElement Parent)
        {
            return new SolidPen(Document, Parent);
        }
 
        public override void CopyContents(ILayoutElement Destination)
        {
            base.CopyContents(Destination);
 
            if (Destination is SolidPen Dest)
                Dest.color = this.color?.CopyIfNotPreset(Destination.Document);
        }
 
        public override async Task DoMeasureDimensions(DrawingState State)
        {
            await base.DoMeasureDimensions(State);
 
            if (this.paint is null)
            {
                EvaluationResult<SKColor> Color = await this.color.TryEvaluate(State.Session);
                if (Color.Ok)
                {
                    this.paint = new SKPaint()
                    {
                        FilterQuality = SKFilterQuality.High,
                        IsAntialias = true,
                        Style = SKPaintStyle.Stroke,
                        Color = Color.Result,
                    };
 
                    if (this.penWidth.HasValue)
                        this.paint.StrokeWidth = this.penWidth.Value;
 
                    if (this.penCap.HasValue)
                        this.paint.StrokeCap = this.penCap.Value;
 
                    if (this.penJoin.HasValue)
                        this.paint.StrokeJoin = this.penJoin.Value;
 
                    if (this.penMiter.HasValue)
                        this.paint.StrokeMiter = this.penMiter.Value;
 
                    this.defined = true;
                }
            }
        }
 
        public override void ExportStateAttributes(XmlWriter Output)
        {
            base.ExportStateAttributes(Output);
 
            this.color?.ExportState(Output);
        }
 
    }
}