t-junction issues

[Scoots1m]

Hi All!

 

I've hit the t-junction limit on my map and I'm struggling to understand why I'm anywhere near it. I was hoping someone might be able to shed some light on how to get past this!

I know that a t-junction occurs when a func_detail brush touches a world brush, I've spent a vast amount of time optimising my map to avoid this, here's what I've tried so far:

• Moving func_detail brushes one unit away from any world brushes (used this a lot).
• Using func_brush instead of func_detail when i cant use the technique above for aesthetic purposes. (I don't like doing this, i know func_brush is more expensive)
• Use Propper to convert sections of your map into props. I've already used this heavily, I've converted a lot of my complex geometry into propper models.
• Increase the Lightmap Scale - Not sure why this works, or if it even does. I'm using a lot of temporary textures and everything is already at 128/256.
• Optimized my geometry where possible, e.g Used one brush where I've previously used multiple.

 

I use a lot of instances in my map, most of which are models + a couple of func_detail brushes. I've tried compiling with only world brushes + instance vis groups toggled on the map, and that shows about 30% waterindices (as opposed to 0% without instances toggled on). However it should show 2-3% instead of 30%, as I've inspected the positioning of every single one of my instances and none of the func_detail brushes in the instances touch any world brushes. So I'm at a loss as to why any t junctions are even being created...

 

I've func_detail'ed a huge chunk of the skybox on my map, none of which is touching a world brush, and that's still increased the number of t-junctions. This shouldn't be happening as its a floating batch of func_details nowhere near any world brushes.

 

Does anyone have any experience with this?

Thanks!

[ElectroSheep]

Well on my experience, if you have made everything to counter t-junction overflow and you can't reduce the number of func details, it means that your map have too much func_details and a map too big.

 

Looks like you've put optimization really far so I can't see another thing... :/

[jackophant]

screenshots?

[Scoots1m]

I've taken a handful of screenshots, but I'm not sure how much sense you'll be able to make from them!

http://imgur.com/a/1eBW5

 

One big cause is the CT side skybox http://imgur.com/a/1eBW5#10 . Anything beyond the small ledge (and horrible metal placeholder wall) you see in that screenshot is func_detail, it also wont be walked on by players. You can see by comparing it to the next screenshot that none of it touches a world brush http://imgur.com/a/1eBW5#11 , except the water and its floor, which I've moved one unit away from everything.

 

I'm planning on moving it all to the skybox once i finish the T side skybox, but i cant even compile with it there to test for now.

[Vaya]

that's a crazy amount of funct_detail. maybe pre-fab and remove anything not in the gameplay area for now?

 

[Vilham]

Probably not best to copy exactly the tobacco dock in a game, any location 1 for 1 in a game is a bad idea, not least because it probably won't play well.

[laminutederire]

Is it me or your map is mainly a box visibility wise?

[Scoots1m]

@veya, I've considered using propper to convert the skybox buildings into props, that will help but i didn't want to bump the map size up with models that were only getting used once.

@vilham, I'm happy that someones recognized it The layout isn't identical for the reason you stated, it wouldn't play well as the actual tobacco dock is gridlike. I loved the ironwork there, so i used that to style the map rather than just lifting the layout.

@laminutederire, The top layer is, the lower layer is more complex, but it doesn't need a skybox as its all underground.

[Vaya]

remove the skybox building for now- get the playable area fixed then you can re-review the skybox

[Scoots1m]

The playable area does work, its mostly the skybox that causes the issues.

 

Saying that, I could always change a few func_details to func_brushes in the playable area, but i think that's only going to give me a small % off the waterindices count compared to what the skybox is causing.

[jackophant]

I think props are what you need. I would have modelled those iron frames for the buildings and then filled in with glass. However, you don't have any real visibility blocking on the top layer which isn't good for performance either, and mainly glass buildings for gameplay are just... not great?

What's your aim for this map exactly?

[Scoots1m]

I've propper'ed the window frames in two of the buildings, but hadn't got around to doing it in the other two as i was considering just propper'ing the entire thing.

 

The glass will have curtains and other props blocking player visibility, I'll then be adding some Nodraw world geometry behind them to add in some visleafs to help with performance.

 

I'm aware there is still lots for me to do on the map, I've just not got that far yet due to the t junction issues

[Vaya]

The playable area does work, its mostly the skybox that causes the issues.

 

 

So simplify and remove this brushwork for now. Prefab your skybox brushwork and delete so you can fix the main body of the map.

[jackophant]

What about using more displacements? Even if you just go as far as converting to displacement and not editing the shape?

[Scoots1m]

I take it I would convert some of the touching brushes from func_detail into displacements?

I've used displacements before, but only for its original use of deforming the brushes.

 

I could hide/delete the skybox for now, but I'll have to come back to it eventually as its not solving the problem, just hiding it under the rug until i trip over it again later