Skia4Delphi_VCL sample project raises an exception

[Ralf7 4]

Skia4Delphi_VCL.dproj->Documents->CreatePDF produces an exception. Does anyone else have this error?

[Sherlock 632]

@Ralf7 I am not sure how to reproduce it. I created a new VCL project in D12. Activated SKIA...and now what?

 

OK, now that I understood what this was about. I deleted the unnecessary code.

 

[Ralf7 4]

https://github.com/Embarcadero/RADStudio12Demos/tree/main/Object Pascal/VCL/Skia4Delphi

[Sherlock 632]

Aha, ok. Nope, still no error here. Using the demo sources selected at install time, everything works fine. Have you tried placing a break point in the pnlCreatePDFDrawingSVGClick method, to see when your crash occurs? Perhaps you don't have a PDF reader installed (very wild guess)?

[Dalija Prasnikar 1341]

1 hour ago, Ralf7 said:

Skia4Delphi_VCL.dproj->Documents->CreatePDF produces an exception. Does anyone else have this error?

It would help if you would provide more information about the exception. The demo works fine for me.

[Ralf7 4]

 LSVGDOM := TSkSVGDOM.MakeFromFile(AssetsPath + 'knight.svg');     knight.svg was missing. Arrrrg!

It would be interesting to create a Canvas -> PDF output under Win32. The question arises as to whether the necessary VCL Canvas APIs are all supported.

Edited November 22, 2023 by Ralf7

[vfbb 275]

1 hour ago, Ralf7 said:

It would be interesting to create a Canvas -> PDF output under Win32. The question arises as to whether the necessary VCL Canvas APIs are all supported.

The current design of Vcl's TCanvas makes it unfeasible to create a wrapper that uses different libraries / different outputs. There is already a request to try to improve this and you can vote:
[RSP-43149] Remodel TCanvas to allow injection of a different drawing backend - Embarcadero Technologies

So currently, what can be done is to draw using the APIs directly from Skia, that is, using the document's SkCanvas, or you can draw in a TBitmap in the conventional Vcl way and in the end use:

SkCanvas.DrawImage(Bitmap.ToSkImage, 0, 0);

but I don't recommend this because you wouldn't have a vectorized PDF, and the texts couldn't even be selected/copied, as the PDF would be an image in fact.

Edited November 22, 2023 by vfbb

[Ralf7 4]

You can do that now. You just need to overwrite the base class TCustomCanvas with your own methods. I would like a powerful PDF writer that also supports all Win-GDI writing modes.