Improving 3D PDF support

[petervwyatt]

Not wanting to hijack the Latex3 Tagging Project Issue #868 for a side discussion about media9 and 3D PDF support, so creating here instead. Or we can shift to email or a different GH repo if that is better for you.

AFAICT, the PDF at https://arts-sciences.und.edu/academics/math/calc-1-texts.html does not include any PDF 3D or RichMedia annotation objects with embedded interactive PRC content. Instead, the interactive 3D content is hosted externally on a website. Do you have a version of the PDF with internal PRC content?

I'm also interested in working with you to explore improvements to 3D PDF support from Asymptote/media9/LaTeX that include 3D content in formats such as PRC, U3D, or glTF.

[teepeemm]

I had forgotten that my media9fix.sty broke the PRC embedding. That file should now work. (Although Adobe is the only PDF reader I know of that can interact with the PRCs.)

[petervwyatt]

Your website still says "(last updated July 2025)" but I can confirm the PDF does indeed now have functional 3D PDF PRC data!

I can confirm it works in Acrobat, and the fact it doesn't work in Foxit and Tracker Software has been reported to the respective dev teams, since both of those vendors also support PRC.

PS. The ISO standard for PRC is currently being updated so I want to understand if the PRC files used are valid according to this latest spec, or if they are malformed or using undocumented/proprietary features.

[teepeemm]

The other example is media9's documentation (https://ctan.org/pkg/media9). It's conceivable that is a better example because I added some low level PDF commands in order to get UA-2 validation (so it's conceivable that could break the PRC embedding).

But Foxit cannot use the documentation's PRC either. But the fact that Foxit's handling of U3D is more responsive than Adobe's gives me hope that their PRC implementation would also be more responsive than Adobe's.

("July 2025" is what got sent to the printers, so I'm not wanting to cause confusion with a more recent version than the students are using. I'm guessing that most people won't notice the update.)