Use getPosASLVisual for icons and camera position

[rebelvg]

When merged this pull request will:

• Fix stuttering of the camera and icons when camera is following the unit.
• Moves icons directly to the unit position.

It uses getPosASLVisual and ASLToAGL which simulates what modelToWorldVisual does but it updates properly. Tested this in the spectator we use in my community, works properly for any surface (water, underwater, above ground).

Example video.
Old - https://youtu.be/j7L0hg4POtY?t=0
New - https://youtu.be/j7L0hg4POtY?t=16

[commy2]

So you're saying that modelToWorldVisual is b0rked or used wrong?

[rebelvg]

Some commands can't be used in per frame since BI fixed "teleporting" bug by introducing interpolation to the network code long time ago in arma 2 ao, that's why they came up with these getPosVisual and visiblePosition commands, they work properly if you want to do some per frame visual stuff.

[commy2]

And why doesn't it work for modelToWorldVisual? Broken?

[rebelvg]

No idea.

[commy2]

_unit modelToWorldVisual [0,0,0]

AGL from model center, render scope

ASLToAGL getPosASLVisual

AGL from lowest road contact point, render scope

I don't think these are identical. What would be needed is a getPosWorldVisual, but that does not exist. Manually add the distance from model center to lowest land contact point? That could be determined once via getPosASL select 2 - getPosWorld select 2.
Refresher: getPosWorld reports PosASL from model center.

[rebelvg]

I'm not sure what I'm doing wrong but they report 0 difference for ground units and flying units.
http://i.imgur.com/Hi37S7o.jpg

[kymckay]

I admit I'm not currently familiar with the intricacies of this PR, but based on the video alone it seems like a good fix. However, it's also worth noting I'm currently undertaking a fairly significant refactor/overhaul of the spectator code based on BIs end game spectator code (which has already enlightened me to some things that can definitely be handled better - I suspect their method of icon rendering should also prove foolproof).

As for moving the icon to the exact position of the unit, personally I preferred it above the unit so that it isn't obscuring anything, but if this is preferable to most people I see no reason not to make the change.

[kymckay]

This PR will be made redundant by #5171 (which I expect to have ready to merge fairly soon). However, it could be merged in as a temporary fix if a release occurs before that PR is merged.

[kymckay]

This works as a temporary fix until the overhaul is complete. I back-ported the new unit icons too 😃