[TF2] Support for more than one activity in a sequence.

[arctic-dino]

Having to specify the same animation over and over again for different activities (like one animation for running with a primary weapon and specifying the same exact sequence again but for a melee weapon) leads to file size bloat. Sometimes people like to include custom models in their maps but unfortunately the player has to specify multiple sequences for what is the same animation thus wasting space.

So instead of this for example:

$sequence "PLAYER_run_item1" {
	"anims/pm0740_00_fi21_run01.smd" 
	activity "ACT_MP_RUN_ITEM1" 1  	
	fps 60
	loop
}

$sequence "PLAYER_run_item2" {
	"anims/pm0740_00_fi21_run01.smd" 
	activity "ACT_MP_RUN_ITEM2" 1  	
	fps 60
	loop
}

$sequence "PLAYER_run_loser" {
	"anims/pm0740_00_fi21_run01.smd" 
	activity "ACT_MP_RUN_LOSERSTATE" 1  	
	fps 60
	loop
}

It would be:

$sequence "PLAYER_run" {
	"anims/pm0740_00_fi21_run01.smd" 
	activity "ACT_MP_RUN_ITEM1" 1  	
        activity "ACT_MP_RUN_ITEM2" 1  	
	activity "ACT_MP_RUN_LOSERSTATE" 1  	
	activity "ACT_MP_RUN_MELEE" 1  	
	activity "ACT_MP_RUN_MELEE_ALLCLASS" 1
	activity "ACT_MP_RUN_SECONDARY" 1 
	activity "ACT_MP_RUN_PRIMARY" 1  	
	activity "ACT_MP_RUN_PDA" 1  	
	fps 60
	loop
}

[VortexParadox]

Why not handle it with a $definemacro?
But I don't see how the extra lines are really a cause for concern when you are using a 60 animation frames per second SMD. If that's not just an example