capture: Add bxt_cap_start_segment

[khanghugo]

Closes #56

Still WIP but it works. There are some details worth discussing and a bug looking bit too much to fix.

Right now, it couples with "bxt_play_run/folder" and it will ignore "bxt_cap_start" argument. Not sure what the argument should mean but in the mentioned issue, I propose to have it as the prefix for the file name ("prefix_demoname.mp4" as a result). But that route needs #57 to be properly addressed. Otherwise, I think the argument could mean THE file name and following split will have number trailing ("filename_number.mp4"). That is what I can come up with to still have "bxt_cap_start" around.

If we go with the prefix, the demo name of the first demo seems a bit too much to get. I look around the source and getting the demo file name is really tricky. demo_playback.rs module does help getting the name but it still does not show the name of the first demo. Maybe I need to get good or go dirty.

For the time being, I don't think this would be useful for live TAS recording so I don't think it needs to be here.

[YaLTeR]

Maybe instead of a new cvar it should be a new bxt_cap_start_with_autosplit (with a less awkward name ideally)? Then there's no problem and it's orthogonal.

[khanghugo]

Alrighty then. I got your permission.

[khanghugo]

So this will output all of the demos in a directory instead. Some stuffs still need adding on. First is first demo will not have its name saved anywhere, even in the game because I don't really know why. So it just needs the demo_playback module to have a state and get the name of currently played demo from there. The next thing is just some helpful console messages. One minor detail, the command is now bxt_cap_start_segment because it is easy to forget to write it and the command is shorter without it.

[khanghugo]

This state should be good. Maybe pattern is needed but this guy on Windows says it is working for him so I am not sure if it's needed.

Take a look at this one first before you get to the other one because I add some changes of this one to another so it looks very messy...

[YaLTeR]

Did not review everything yet

[YaLTeR]

Could you clarify this comment please, my mind reading is pretty rusty lately

[khanghugo]

I might miss something but here is what I recall vaguely happens when bxt_play_run/folder do things:

1. Things set up and happen then demo_playback::set_next_demo is called. The name of the first demo is in the cls.demos array.
2. Prepend the command "demos".
3. "demos" calls Host_NextDemo.
4. demo_playback::set_next_demo is called again. The name of the second demo is now in the array instead.
5. The first demo is played, but cls.demos stores the name of next demo.

So, if I reset the name of currently playing demo name in that hooked function, the name of the first demo will not be known. CL_Disconnect is called along with the Host_NextDemo.

[khanghugo]

To add on, CL_Disconnect is called before setting the next demo. So clearing the current demo name on disconnect will not make the name of the current demo known.

So it is better to use "bxt_cap_start_segment" with "bxt_play_run/folder". I hope no one would try to do something not intended, haha.

This all happens because of the first demo specifically. If first demo name is known then ig. But I guess this would means some changes to how "bxt_play_run/folder" works.

[YaLTeR]

I reworked this how I think it should be implemented and work. I renamed the command to bxt_cap_separate_start (as in separate videos). Please test it out and tell me if it works, and if it works as you expect it to work. If something doesn't work as expected, please say, so I can think how to change it.

[khanghugo]

Thanks.