After just seeing the last livestream, I have a question: How big/coarse are the collision boxes around units going to be? Are you just drawing a big cube around the object? The other extreme would be using the actual 3D model of the object for collision detection. The reason I ask is because I have seen some games where units got stuck or bottlenecked while visually there seemed to be enough space for them to move around in. The underlying reason is that those games used very coarse collision detection and the pathfinding algorithm was basically saying: "Yeah, that's not gonna fit, go around." I would love to see that the pathfinding is detailed enough that if it fits together on screen (Like the 3D models not overlapping anywhere), you can actually do it. Same applies to units close to other units and not just units vs the terrain. In the video you mention if you wanted you could have units bump into other units. Do you mean, bump the collision boxes against each other? Or on a more detailed level and actually use the 3D models. On screen the units would then be visually touching each other. I apologize if this question has been answered before but a forum search didn't turn up anything.
Whatever the collision proxy is going to be I do hope it fits fairly neatly around whatever unit is being represented.
this is not an fps where hitbox size really matters. Its basically unnoticeable in a game with many units so small like supcom.
I have seen this happen in supcom. Units got stuck and refuse to move while there is enough room around them. (once had 3 ML on the map that refused to budge) When you mention the word hitbox I think we are not talking about the same thing. I mean the representation of an object in the flowfield. Would PA just draw a big invisible box around anything that affects pathfinding? Or are they using something more complex? If they were using the actual 3D model you can do real fancy stuff like have a tank drive between the legs of a bigger unit. Because the pathfinding would be able to see an opening there. If they just drew a big box around the big unit this would not be possible. I know I am nitpicking about a very small detail of the game. I understand if the devs come back and say "Yeah, we can't do that it would kill the performance of the game." Or if they think it is simply not worth the time fussing about it.
In supcom driving underneath the legs of a megalith for example was handled by raising the collision box off the ground.
Which is a good solution for pathfinding and keeping the cpu usage down, but the downside is that the unit legs have now become invisible for the collision proxy. The visual effect of this could be seen when a unit drove right trough one of the legs of the megalith. I guess it is all a trade off between performance and eye-candy.
In terms of navigation a big unit could paint cost at its feet. There's still the issue of projectile collision I guess.
I've always preferred a more flexible approach to unit collisions, where the collision hulls are treated less like concrete and more like sponges, so at times they can actually squeeze together much tighter than they probably should be, like when there's a large number of units trying to squeeze through a small area, but they will spread out again once they are through it and there is room to do so. IMO it looks better and it can be done relatively cheaply, the only trade off is occasional clipping but it's hard to notice that when you are zoomed out. IIRC Starcraft 2 uses something similar to this sort of approach, sometimes the units can get all bunched in a small area but most of the time are spread out like you would expect.
You actually have two totally different "collision boxes" used. For one, there is the real collision box which is used for any kind of collision test, most likely a simple border box and a more detailed collision box if border box test succeeded. The other is an implicit effect which is achieved by the formation system which is part of path finding. Units will try to keep an healthy distance from each other which is not related to any hitbox, but they will move closer if that distance can't be maintained. The actual collision box comes only into play if collision can't be avoided (if at all, might also happen that at least own units behave more like sponges, in that they completely ignore collision with each other, but can be compressed in really tight spots as long there is sufficient force. I don't hope for this though.)
