SmoothImage.cs

using SkiaSharp;
using System.Threading.Tasks;
using Waher.Script.Abstraction.Elements;
using Waher.Script.Exceptions;
using Waher.Script.Graphs;
using Waher.Script.Model;
 
namespace Waher.Script.Fractals
{
    public class SmoothImage : FunctionOneScalarVariable
    {
        public SmoothImage(ScriptNode Argument, int Start, int Length, Expression Expression)
            : base(Argument, Start, Length, Expression)
        {
        }
 
        public override string FunctionName => nameof(SmoothImage);
 
        public override string[] DefaultArgumentNames => new string[] { "Image" };
 
        public override bool IsAsynchronous => true;
 
        public override IElement Evaluate(IElement Argument, Variables Variables)
        {
            return this.EvaluateAsync(Argument, Variables).Result;
        }
 
        public override async Task<IElement> EvaluateScalarAsync(IElement Argument, Variables Variables)
        {
            PixelInformation Pixels;
 
            if (Argument is Graph Graph)
                Pixels = Graph.CreatePixels();
            else if (Argument is SKImage Image)
                Pixels = PixelInformation.FromImage(Image);
            else
                throw new ScriptRuntimeException("Expected an image or a graph.", this);
 
            int Width = Pixels.Width;
            int Height = Pixels.Height;
            PixelInformationRaw Raw = Pixels.GetRaw();
            byte[] Bin = (byte[])Raw.Binary.Clone();
            int i, j, c = Bin.Length / 4;
            double[] R = new double[c];
            double[] G = new double[c];
            double[] B = new double[c];
            double[] A = new double[c];
 
            for (i = j = 0; i < c; i++)
            {
                B[i] = Bin[j++];
                G[i] = Bin[j++];
                R[i] = Bin[j++];
                A[i] = Bin[j++];
            }
 
            (double[] BoundaryR, double[] BoundaryG, double[] BoundaryB, double[] BoundaryA) =
                FractalGraph.FindBoundaries(R, G, B, A, Width, Height);
 
            await FractalGraph.Smooth(R, G, B, A, BoundaryR, BoundaryG, BoundaryB, BoundaryA, Width, Height, this, Variables);
 
            return new GraphBitmap(Variables, FractalGraph.ToPixels(R, G, B, A, Width, Height));
        }
    }
}