Day 7 - Navmesh Hell

I burned most of the day working out a few subtleties in Unity's navmesh system. I'm not 100% happy with the way I put it together but its largely functional.

The navmesh system builds simple geometry and you use this geometry to navigate around your map. The problem I ran into is my towers are static, meaning they never move so Unity was cutting out holes in the navmesh for them. This is intended behaviour. Later, when I tried right clicking to attack them I would have to move my player within range of the tower to use his auto-attack. This is where the problems began.

The intended behaviour is that Unity provides a position that is the nearest edge to where you clicked. However, this turned out to vary wildly per click and made closing to weapon or spell range sporadic and sometimes just plain buggy.

The fix I used was to include a navmesh obstacle onto the tower and to re-bake the navmesh without the tower. This allows the right click to always land on the navmesh and for the player controller to accurately close distance so you are in spell or weapon range.

The downside is you can walk right through the tower as if it isn't there.(per the navmesh system it isn't), the navmesh obstacle makes your character controller avoid it, so you could technically still walk through it, or be pushed through it by another agent, however in light testing it appears to be holding up as intended.

That worked through, I've implemented a very basic combat system. Right clicking an actor that is not on your team causes you to close to auto attack range and start auto attacking. I've equipped the player with a fireball spell that autocasts every 2 seconds as long as he's in range.

Attacks do damage and the tower will quit firing when it's "dead". The player has health, but is still immortal at the moment.

I've also begun the basics of the creep AI. Right now if he's on your team he'll attack enemy towers or move to a waypoint I've set up. If I switch him to the opposing team he'll chase the player around until you leave his range of vision.

All in all it's been a decent couple of development days. The navmesh issue burnt a lot of time but appears to be mostly conquered at this point.

I've also implemented a very basic GUI using DaikonForge. The design time tools are great but I found out after purchasing it that it doesn't handle world space GUIs at all. This means I'll have to roll my own healthbars and damage numbers.

Time for the obligatory video:

this shows a creep chasing me around and then attacking a tower, it also shows the tower attacking the creep and me attacking the creep. Nothing fancy yet, still a lot of plumbing work to do.