MultiPlot in notebooks without system.drawing

[yueyinqiu]

Hello! I'm trying to have something like subplot in matplotlib. But I have found that the MultiPlot Class has been removed.

I have viewed #992, but System.Drawing does not work for the platforms other than windows. Also #3479, but I'm using polyglot notebook, without plot controls or something else.

I tried to do that like this:

    public static Image AsImage(this IEnumerable<Plot> plots,
        int columnCount, int plotWidth, int plotHeight)
    {
        var plotsArray = plots.ToArray();

        var height = (plotsArray.Length + columnCount - 1) / columnCount * plotHeight;
        var width = plotWidth * columnCount;
        using SKSurface surface = SKSurface.Create(new SKImageInfo(width, height));

        var left = 0;
        var top = 0;
        foreach (var plot in plots)
        {
            var right = left + plotWidth;
            var bottom = top + plotHeight;
            plot.Render(surface.Canvas, new PixelRect(left, right, bottom, top));

            if (right == width)
            {
                left = 0;
                top = bottom;
            }
            else
            {
                left = right;
            }
        }
        return new Image(surface);
    }

But it only keeps the last plot, while the rest part of the image seems to be cleared.

So is there a simple solution to that? Thanks in advance.

[yueyinqiu]

Oh I just realized that ScottPlot relies on SkiaSharp. I can use it without any burden now.

    public static SKBitmap ToSKBitmap(this IEnumerable<Plot> plots,
        int columnCount, int plotWidth, int plotHeight)
    {
        var plotsArray = plots.ToArray();

        var height = (plotsArray.Length + columnCount - 1) / columnCount * plotHeight;
        var width = plotWidth * columnCount;

        var bitmap = new SKBitmap(width, height);
        using var canvas = new SKCanvas(bitmap);

        var left = 0;
        var top = 0;
        foreach (var plot in plots)
        {
            using SKSurface surface = SKSurface.Create(new SKImageInfo(plotWidth, plotHeight));
            plot.Render(surface.Canvas, plotWidth, plotHeight);
            canvas.DrawSurface(surface, left, top);

            left += plotWidth;
            if (left == width)
            {
                left = 0;
                top += plotHeight;
            }
        }
        return bitmap;
    }

(P.S. In my case, SKBitmap is ok. If anyone wants Image, could just use return new Image(bitmap);, but don't forget to dispose bitmap.)