The movie player code was missing some important functionality, in particular:
1) There was only one timing method to get real-time elapsed time, which was not suitable for pausing or time compression
2) There was an improper cast for the FPS property, causing a script error
3) The `getSeconds` method lost precision during casting
This patches those deficiencies.
A bit overkill for some of this but just covering the bases.
* fix issues with in-game join
* fix multi messaging and multi pause screen
* make sure maintenance stuff (pings, voice, file xfer, etc.) isn't
affected by pausing or time compression
This adds a type-safe TIMESTAMP, similar to UI_TIMESTAMP. Eventually all of the FSO codebase will be switched over to this new type. In the meantime, just the supernova code is switched over.
If a breakpoint is hit in the code, the SDL time will keep running even though FSO doesn't realize things are effectively, if not actually, paused. Detect this situation and adjust the timestamp offset to compensate.
Previously, the game used a dead-reckoning system for measuring time, where several time counters were incremented as long as time was running. This unfortunately has no way to synchronize time in the long term, and therefore in-game time will tend to run faster or slower than real time by a few percent, depending on various factors.
This PR redesigns the timestamp system to use the SDL time counter which will always keep it in sync with real time. However this necessarily involves a bit of clever handling when the game is paused and unpaused. It also revealed several minor bugs in several places in the code where timestamps were handled.
This PR is currently in draft status until the design can be updated to handle time compression. In all other respects it should be working.
Goober5000