Is there a replacement for ImmediateRenderer in v11.0?

[FreddyDgh]

@kekekeks I see in Avalonia v11.0 that ImmediateRenderer has been made internal in #10078. Looks like it's been dropped in favor of the CompositingRenderer. Previously, I had been rendering static content to a Skia canvas like so:

IVisual visual;

using var context = new DrawingContext(DrawingContextHelper.WrapSkiaCanvas(canvas, SkiaPlatform.DefaultDpi));
ImmediateRenderer.Render(visual, context);

Is there an easy equivalent to render static content to a Skia canvas like this in v11.0, either via CompositingRenderer or some other mechanism?

[maxkatz6]

I don't think there is now.
You can draw over a wrapped skia canvas:

using var contextImpl = DrawingContextHelper.WrapSkiaCanvas(canvas, SkiaPlatform.DefaultDpi);
using var context = new DrawingContext(contextImpl);
context.Draw...

Or you can render existing controls to RenderTargetBitmap:

 using (var bitmap = new RenderTargetBitmap(pixelSize, dpiVector))
 {
    bitmap.Render(root);
    bitmap.Save(destination);
 }

But I don't see any way to combine RenderTargetBitmap with a custom drawing context.
CC @kekekeks

[FreddyDgh]

Thanks for the reply; it is helpful for planning. Ultimately, I think it does make more sense to have the ImmediateRenderer be internal and expose the functionality through something like a RenderTargetBitmap that allows for a custom drawing context. The Skia rendering functionality is nice to have for my scenario, but not strictly necessary. Seems reasonable to put priorities elsewhere.

[maxkatz6]

Actually, I was wrong. It should be possible with this code.
Something like this should work

private void DrawVisualToCanvas(SKCanvas canvas, Visual visual)
{
    using var contextImpl = DrawingContextHelper.WrapSkiaCanvas(canvas, SkiaPlatform.DefaultDpi);
    using var context = new DrawingContext(contextImpl);

    using var bitmap = new RenderTargetBitmap(new PixelSize(100, 100));
    bitmap.Render(visual);
    contextImpl.DrawBitmap(bitmap.PlatformImpl, 1,
        new Rect(0, 0, 100, 100),
        new Rect(0, 0, 100, 100));
}

Just need to adjust sizes, probably get it from the visual bounds.

[FreddyDgh]

The DrawBitmap method will draw the rendered UI to the canvas, but it is not entirely the same as rendering with the Skia drawing context. For example, if you save the SkiaCanvas to a PDF file, you will not be able to search for text in the PDF file, because what gets saved to the PDF is not actually text - it's all one big image.

[maxkatz6]

For 11.1 (nightly currently) you can also use this method: https://github.com/AvaloniaUI/Avalonia/blob/master/src/Skia/Avalonia.Skia/Helpers/DrawingContextHelper.cs#L14

[FreddyDgh]

Just got a chance to try this out. It appears to work exactly how I wanted, so hopefully it will come to stable soon. Thanks for your efforts.

[maxkatz6]

It is already