Difficulty :

Short description : Aims to unlearn something that might be useless when it comes to Boomer textures, in order to simplify the modding process, with less VMTs needed (good if you want Boomer textures but struggle with the 32 VMT limit).

Time to implement : 0 seconds. This mod aims to remove a step for modders.

Needed skills :

• The ability to make a character mod.
  
• ''Knowing'' how to put Boomer textures in a survivor mod

If you know how to make characters mods for L4D2 on your own, first of all, congratulations and thank you for bringing to the community awesome mods and make L4D2 live since all these years.
If you mod characters, you might have at one point wanted to add Boomer texture effects on your characters mods, and since you probably didn't learn to make character mods by yourself, you probably read a guide about it. The problem is that guides are incorrect about the minimal required steps to implement boomer textures, because one major step is not needed if you do not plan on using a $detail texture.

The error itself does not break any mod, it's not unsafe or unstable, however, it doubles the VMTs in your mod, because, and you probably do it that way, you use two pairs of VMTs, one normal and one with _it at the end.
This results in another problem, since models usually have a 32 VMT limit. So for more complex mods that requires a lot of VMTs, people usually do not implement Boomer textures.

In other words, if you learned how to add boomer textures reading this, this is NOT ALWAYS NEEDED. You do not need this step if you do not plan on using $detail.

The (possible) useless step in мяFunreal's Custom Playermodels Guide

The (possible) (former) useless step in ZeqMacaw's Modding a Left 4 Dead 2 Survivor Guide

The (possible) useless step in Splink's Custom Survivor Replacement Guide

The (possible) useless step in Oachkatzlschwoaf™'s L4D2_Custom_Survivors Guide

This is the only thing you need to do if you want Boomer bile effects on your survivor.
You need to repeat these steps in all VMTs that need to have Boomer effects.

Add one
at the end of your VMT.

If you do not do this, it will still work, but you will get errors in console.

See this thing at the beginning of your VMT ?
REPLACE it with that

That's it, you're done, Boomer effects are now activated. Just do that in every VMT and you're good !

What probably happened is that at the very beginning of L4D2 Modding, Splinks and other modders made the first guide ever about Modding Survivors in L4D2 which helped a lot of people, but that contained the (mostly) unnecessary step that was later passed on every other Guide and between modders.

Of course, they looked at the default files and the ones provided by Valve in the VPK, and there was all the reasons in the world to believe a modification in the .qc with skin families and double _it VMTs was mandatory because that's actually how the original game survivors are done after all and how the modding material Valve itself provided was set up.

There was also all the reasons in the world to believe that the only way to display boomer texture was to "swap" the models when the Boomer vomits, since that's how the game works. So why is this step unnecessary ?

It turns out that actually, almost everything that changes the Boomer Bile texture in handled by Materials Proxies in the VMT. The patch {} thing you need to do is a way to include a VMT file in the game that contains a code to display Boomer textures. This code changes the $detailblendfactor of a $detail containing the Boomer vomit, which is gotten by a Proxy. If you just insert that code in the VMT, the result is the same.

These are the only lines that handle the boomer effect, found in the survivors_it_shared.vmt:
Copying these lines in any VMT will activate the Boomer effects on its own !

Originally posted by you:

Well, okay Ellie, that's nice, but that still doesn't explain why the original survivors have all these double VMT with _it.vmt for the Boomer. You do not seriously think that Valve's developers went in all that trouble for something that is useless? You must be wrong.

To this, I can answer that yes, there is a reason why the developers coded the game this way.
The reason is that it is not possible to change the $phong settings after the model is rendered, using Material Proxies. In other words, the code above is unable to change $phong settings on its own because of engine limitation. Therefore, the developers, that wanted special $phong settings on the survivors, had only the option to swap the models when the Boomer vomits. That's the reason why it exists, and you should actually ignore that Guide if you actually want different $phong settings for when the Boomer vomits... but well, I've seen very few mods that way.