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Comment by lukan | Hacker News Reader

"swap in a pdf or svg backend"

I am not sure, if I understand you right, but do you mean rendering to pdf or svg instead of the GPU?

If so, are there real world use cases?

"crushes Skia in performance without sacrificing a ton of capabilities"

Same question, what of those capabilities are really in use and needed? Linux GUIs in general are really not a beacon of light, in terms of performance or usability. I strongly suspect things could be better, if some bloat would be removed.

I am amazed with what is possible with PixiJS, a renderer for the Web, using WebGL and soon WebGPU. Having something simple, but powerful as the base, would be my way to go.

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Printers often want pdf or postscript. Or if not some other format that isn't a regular GPU supported thing. Games rarely support printing, the main use is take a screenshot which uses the OS not the game engine, which is great for games. However if you are writing something where printing is important you want more control over the output than a screenshot can give (printers tend to be much higher resolution, but you have to deal with paper size - two things that should be passed back to the application as you can often make adjustments to better use show things when you know those limits - there are other compromises in printing too that may matter)

Saving websites as PDF comes to mind. If taking screenshots of windows as SVG was possible I would definitely use it.

A screenshot of a rasterized image saved in SVG is not something I see any use for. It will be a bloated monstrosity.

SVG is vector graphics, when you already have pixels - there is no clear way going back.

SVG files can refer to images for bitmap graphics, only the rectangles, text, etc would be specified as vectors. See https://www.joachim-breitner.de/blog/494-Better_PDF_screensh... for a demo.

I think he means taking the scenegraph and saving it directly to SVG. Pretty much how it would be done for PDF.

Ah, right. Does not sound too complicated, but is an entirely seperated render path. And apparently now supported? But I have never seen it put to use.

Cairo and Skia can do this.

But is there a real world use case, where this actually was put to use?

(Sorry, I am having flashbacks of the debate with X and wayland, where it was argued, but X is network transparent, except that it wasn't anymore since a long time and, or because - no one used it)

The "Save to PDF" feature in Firefox's print settings uses the Skia-to-PDF renderer on various platforms, I believe.

And for SVG?

Having features is nice, but not if they are not really necessary and come at the cost of the core feature (performant screen renderer).

The problem here, is that you have no clue what the core features of a UI toolkit need to be.

If performance was the primary concern, GTK and QT, would not be generations behind (a claim I am skeptical of.)

UI toolkits have a much larger audience than the tiny corner of the industry you work in.

Well, it just so happens that I build a UI toolkit over the last decade, but yes with performance in mind and not featuritis. But apparently I have no clue, well sad to hear that. I'll show myself out.

The use case is usually sending the screen to the printer or saving a document.

It seems super complicated to me :-) cool idea though

I got the impression from above, that this is something possible now, yet I have never seen such a capability. And I thing the effort will be way greater the reward to implement from scratch ..

("Easy" assumed, there is already something there)

Um, isn't that an application feature?

How do you expect applications to implement it without a renderer?

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