add event handler for creating and deleting markers

[commy2]

When merged this pull request will:

• Adds CBA_fnc_addMarkerEventHandler and CBA_fnc_removeMarkerEventHandler
• Supports created and deleted events
• Passes the created or deleted marker name as _this

@bux578 is that what you needed?

[bux]

@commy2 Looks perfect. How bad could performance suffer if allMapMarkers is checked each frame?
Maybe a slight delay could make sense here?

And what about automatic generated markers like from Blue Force Tracking etc...

[commy2]

How bad could performance suffer if allMapMarkers is checked each frame?

I don't think much. allMapMarkers is not like nearestObjects. It just reads an already existing array out of C++ land afaik.

Maybe a slight delay could make sense here?

maybe. although if you make the delay too big, you could miss some obviously. I guess 0.1 is fine?

And what about automatic generated markers like from Blue Force Tracking etc...

it would execute for every marker that appears in allMapMarkers

[jokoho48]

why not using a Statemachine?

[commy2]

There are no states here.

[nicolasbadano]

I'm not sure about the delay; all CBA event handlers are instantaneous as far as I know, and having these ones behaving differently might be confusing. Also, it might break some potential usages that require low latency.

It all comes down to the cost of:

private _newAllMapMarkers = allMapMarkers;
if !(_newAllMapMarkers isEqualTo GVAR(oldMarkers)) then {

have you measured the performance of that?

[commy2]

oldMarkers = allMapMarkers;

private _newAllMapMarkers = allMapMarkers; 
if !(_newAllMapMarkers isEqualTo oldMarkers) then {};

0 markers: 0.0036 ms
100 markers: 0.0148 ms

100 markers using private _newAllMapMarkers = allMapMarkers:
0.0137 ms

So allMapMarkers does get slower with many markers placed, but it isn't that bad. Not sure if that should run every frame though.

[nicolasbadano]

This are the theoretical frame decreases of running this every frame with 200 markers (assuming 0.015 x 2 = 0.03 ms):

60.0000 fps ->59.9999 fps
90.0000 fps -> 89.9997 fps
120.0000 fps -> 119.9995 fps

All in all completely unnoticeable.

[commy2]

reverted it :)