Precaching of pages in memory

[nver]

When viewing pdf documents and scrolling more or less complex pages (image-based), the newly appearing parts get drawn gradually and it is seen even on not so slow processor. A feature to optionally "predraw" the previous and next page (as if it has been already viewed) would be nice.

[Stefan - PDF-XChange]

Hi nver,

Depending on the scrolling speed and the size of the images inside your file it might not be possible for the computer to catch up to that speed, even if there was some "preemptive" rendering.
While there are lots of optimizations done in our viewer, some tasks are not easy (in terms of computing resources needed) and should only be undertaken when needed, and as you are free to jump from page 1 to e.g. page 22, the viewer can not try to "predict" and consume valuable resources needed elsewhere in your system (if we were still in dos environment and only one application was running at a time... but that's another story )

We are planning to introduce similar algorithms to the viewer that would allow for autoscrolling, but there are no such tricks up our sleeve for now.

Cheers,
Stefan

[nver]

I was talking about an option to predraw the next page for reading in consecutive order. Of course it is not possible to do this immediately. It could be done in a low priority thread and if user paused on a page for a while and there are no cpu-intensive tasks running in the system, the next page wouldn't have to be drawn in real-time. That would be more beautiful. For example when reading a pdf-magazine with lots of pictures, I scroll it page by page and I stay on one page more than enough for the next page to be drawn (a page draws in 3-4 secs).

[Stefan - PDF-XChange]

Hi again nver,

Your point is clear, it's just that at this moment our Viewer is not trying to do such pre-rendering.
As I already told you we have it planned and under development so eventually it will happen - but as of when exactly I can not tell at this moment.

Regards,
Stefan

[nver]

Hello, Tracker Supp-Stefan
Got it. Thank you for the reply

[John - Tracker Supp]