Probably supporting 100% of the PDF spec. plus addressing all those obscure feature requests that 6 companies in this one very niche industry really really need. Sumatra is fantastic and basically the only PDF reader I use on Windows, but it does have maybe 10% of the features Adobe acrobat has. It is however the 10% that that basically everybody needs.
I agree that Adobe has more features than SumatraPDF.
Not necessarily the PDF spec itself - SumatraPDF displays pretty much any PDF you throw at it, just way more options and stuff.
And it's not exactly slow. I'm sure the core rendering of PDF pages is same or faster.
It's just slow to start. Like very, very, sluggish slow. And it's very visible to users.
I don't think it's the features that cause the slow startup. They just don't seem to care about optimizing it.
Chrome has more features that Adobe Reader. It has video calling, a capable PDF viewer and all the other stuff in ever growing web standards.
And yet it starts up fast. Not instant as SumatraPDF but way, way faster than Adobe Reader.
I think that it's more than fair benchmark regarding complexity of the app.
The difference is that Chrome team cares about performance, including startup speed, and they spend a lot of resources on it.
I remember Chrome was counting and removing C++ static initializers from their code (the code that runs before main()) because that contributes to startup speed.
That's the level of care you need to have and I think Adobe just doesn't have it.
Sumatra includes a 3D renderer to display embedded CAD models? https://helpx.adobe.com/acrobat/using/displaying-3d-models-p...
As for startup speed, it's not really an issue as Adobe just lurks there all day in the taskbar for me at least ready to roll.
More / better annotation editing, signing, redaction is something I want to do.
OCR - I don't have a good handle on how important that is.
I would much rather throw this money your way, but I need those features
I often use PDF applications for documents that I want to keep for decades, including annotations I make. How much can I count on SumatraPDF, or any PDF application, outputting future compatible documents from conversions, annotations, deleting/merging/etc, content editing, etc.? Is there a difference between applications?
My instinct is to play it safe and use Adobe, figuring whatever they do is the de facto standard. But I strongly dislike the applications and all the privacy invasions they impose. (Yes, I'm aware of PDF/A; I'm talking about applications' outputs and not the standards.)
I will say that on older systems, Reader/Acrobat are not just slow at startup. I am writing this from a machine that has an i7-2600 and 16GB of DDR3 RAM. Reader is almost unusably slow. It's absurd.
Now where's that Mac port? /s
I’m a high school math teacher and scan dozens of textbooks every year. Adjusting a few words before printing to match what we did in class is a huge time saver for me.
Somehow my school division was able to buy me a one time fee perpetual license. I’m very happy with it.
It looks like it's Linux only (I only have Linux so I hadn't checked before), but when I want to sit down and properly read something, the keyboard-centric UI and minimalism make it a really smooth and frictionless experience.
There's a mupdf windows build. Perhaps that will do what you want.
(Mupdf is also a library so there are a lot of different programs with the name in it by various programmers.)