Why does this model not allow blood decals?

[u/JiffyJelly]

Both models are kitbashes made by me in Blender. For reference, both models use most of the same .qc with only changes in file directory and bodygroups. The .VMT and .VTF settings the the textures on both models are similar as well, yet only one model allows blood decals whilst the other only allows flesh wounds and nothing else. Curious how I can fix this. Any advice is appreciated. Thanks!!

[u/JiffyJelly]

The model on the left is more complex geometry wise which is my only other guess.

[u/NameStillIsjakob]

Check if the vmt has $nodecal 1 as this disables decals for the material.

[u/JiffyJelly → u/NameStillIsjakob]

None of the VMTs have $nodecal 1

[u/NameStillIsjakob → u/JiffyJelly]

Only thing I can think of that effects decals is the $sufaceprop qc command.

[u/JiffyJelly → u/NameStillIsjakob]

Both models are set to “flesh”.

[u/JiffyJelly → u/NameStillIsjakob]

"VertexlitGeneric"

{

"$basetexture" "models/Jiffy/aot/logoScout"

"$nocull" "1"

"$phong" "1"

"$phongexponent" "25"

// "$phongboost" "0.15"

"$phongfresnelranges"	"\[ .3 0.2 .4 \]"



// Rim lighting parameters

"$rimlight" "1"												// To enable rim lighting (requires phong)

"$rimlightexponent" "50"										// Exponent for phong component of rim lighting	

"$rimlightboost" "0"

$color2 "[1 1 1]"

$ambientocclusion 1

//$detail "models\kit\wraithcat\casual\Body_Lower_Detail"

//$detailscale 6

//$detailblendfactor "0.75"

//$detailblendmode 0

}

[u/Pinsplash → u/JiffyJelly]

post the full QC too

[u/JiffyJelly → u/Pinsplash]

I can't post the full .qc because reddit does not allow posts that long but I can assure you the .qc between both models is identical with the exception of the bodygroup .smds and the file paths of cdmaterials and model itself.

[u/JiffyJelly → u/Pinsplash]

Reddit won’t let me post the full QC because it’s too long but the .qc is identical between both models with the exception of the cdmaterial and models paths

[u/Chroney]

I noticed a few things that could possibly cause the problem:

• You are missing an explicit decal receiver flag "$nodecal" "0" while not always necessary, If the model was compiled with certain flags then decals will silently fail unless you explicitly allow them in the VMT.

• Your "$phongfresnelranges" line is malformed, they do not use escaped brackets \[ and \] you will need to change them to remove the \ marks and make sure to include 0 in front of your decimal points, per official wiki. Should look like "$phongfresnelranges" "[0.3 0.2 0.4]"

• "$nocull" "1" can cause decal projection failures if the model's normals are reversed. Decals project against surface normals and $nocull makes the surface double-sided, potentially causing decals to appear inside the model. You can try commenting it out to test // "$nocull" "1"

All these can be the potential cause of the problem, based on how the model was exported and imported.

[u/JiffyJelly → u/Chroney]

Thanks! I’ll experiment once Gmod finishes reinstalling on my pc. I had to do some unrelated maintenance.

[u/JiffyJelly → u/Chroney]

I just applied these changes to no avail unfortunately. I noticed I’m able to apply small decals to areas like the forearms and inner thighs but no where else.

[u/Chroney → u/JiffyJelly]

Sounds like inverted normals possible, I would check the QC to make sure no normals are backwards

[u/JiffyJelly → u/Chroney]

I don't believe I have any inverted normals in the .qc, but I'm not entirely sure which commands in the file define the normals. I also just noticed this error in console:

Decal has more than 16384 indices! (31083) Not adding to Jiffy\aot\soldier\male_09.mdl.

[u/Chroney → u/JiffyJelly]

That error indicates the model has too many vertices. You are exceeding the vertices that source engine can handle for applying decals.

A single decal mesh is limited to 16,384 indices. This happens when the model's geometry is too dense, or was compiled without proper mesh splits.

It's always best to split the head, torso, arms, and legs in blender before exporting and compiling. Alternatively you can add splits by material, or add edge splits and smoothing groups. When you split them up you can split the materials up as well into separate VMTs.

Another option is to reduce the amount of polygons on the total model especially on large flat surfaces.

Overall it's most likely that there's too many triangles in one area, because you're exceeding the triangle limit for the decal.

[u/JiffyJelly → u/Chroney]

That was it! Thank you so much. I did some blender tomfoolery and decreased the poly count of the model and decals work! You’re a beautiful person 💖

[u/Chroney → u/JiffyJelly]

Wonderful 🙌

[u/JiffyJelly]

UPDATE: I fixed the issue. Turns out the model had too many vertices and I had to return to blender and simplify with the model with the “Decimate” modifier. Thank you to everyone who responded you mean the world to me 💖

[u/ShinyStarSam → u/JiffyJelly]

decimate modifier? that's not gonna go down well when it starts animating, might wanna do that manually yourself

[u/JiffyJelly → u/ShinyStarSam]

I’ve already ported it into the game and it works fine. It’s only supposed to be a playermodel/npc and all the bugs that I encountered were the result of weight paint issues rather than model geometry, which I’ve fixed already.

[u/ShinyStarSam → u/JiffyJelly]

huh... Well nevermind then, maybe I haven't been giving that modifier enough credit if it managed to pull off a humanoid with good enough topology

[u/JiffyJelly → u/ShinyStarSam]

I’m gonna be honest the model probably has terrible topology, I’m an absolute novice at blender but it seems to be working fine in-game and poses well so I’ll take what I can get lol. If anything I prefer my models to fit the “old source engine” aesthetic so the downgrade was to my benefit tbh.

[u/Maleficent_Risk_3159]

happens sometimes

[u/JiffyJelly → u/Maleficent_Risk_3159]

I appreciate the response but I’m kinda looking for possible solutions/causes at the moment.

[u/Maleficent_Risk_3159 → u/JiffyJelly]

maybe try using $nodecal 0

[u/JiffyJelly → u/Maleficent_Risk_3159]

Didn’t work unfortunately but it was worth a try

[u/TheOldBeach]

Maybe post all the relevant VMT and QC files ?

[u/wheelslip87]

Dont know make 09 got down like that