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las modding tutorial
this is a guide on how to make a custom las mod
this guide is outdated, here is the new one
what this guide is about
this guide will attempt to show how you can create custom las mods however the process is pretty long and tedious. also if you don't have any blender experience then this might be very difficult. nevertheless i will try to make this as beginner friendly as possible, however if you still need help then feel free to ask.
tools needed
znix model tool[]
this is different then the main one that you are probably already using. the special thing about this one is that it supports fbx files which is what we need for modding rigged objects

fbx documentation []
if you run into an error while importing a model into the model tool then check to see if the error is in this list.

las helper[] (optional)
a custom tool i made that helps create the files and directories for las modding

blender []
blender is what we will be using however i use blender 2.93 [] which i would recommend since their usually is ui changes between versions

Diesel Bundle Viewer[]
this is for extracting the game files, (if you want so see the newer stuff then you need the hashlist[])

this is the image editing software that we will use.
finding a good model
what to look for
since you are probably a beginner, look for models that do not have a ton of detail. if you want this to go as smoothly as possible then try avoiding models with overlapping parts like capes and skirts. you also don't want to many polygons, try keeping it below 60k triangles as too many faces will destroy the diesel engine.

where to look for models
sfm lab[] has a ton of good models however they are mostly for the source engine, so you will have to use the sourceio [] add-on and vtfedit []to turn the textures into pngs. this is 100% my go-to for finding models.

using vtfedit to turn .vtf into png

taking from other games
you can always take from other games however the main drawback is that different games have different methods of extracting models. its the coolest way but also the hardest.

deviant art also has models but i dont really use that
preparing model and textures
open blender and import the model that you chose

remove shape-keys
i dont actually know if the shape keys will mess anything up but the model tool is pretty sensitive so just to be safe, remove them

remove vertex groups
vertex groups are what the bones control, but since we wont be using this models original bones we should remove them

combining all the textures
more likely then not, the model that you want to import uses multiple texture files, this is a problem since you cant have more than 1 material on a mesh while making a las mod. to fix this you will need to use an image editing software like gimp in order to combine all the textures into one file.

editing the uv
the model will also most likely be made up of multiple parts. remove the original material and replace it with the combined one that you just made. since the new texture that you made is larger, you will have to resize the uv and reposition it into the correct spot. make sure everything is using the same connected texture.

if their are multiple textures on one mesh, you can select a part of the mesh in edit mode and click on select in the material properties (press tab to switch between edit mode)

example of me editing the uv
a = select all | g = move | s = scale | while scaling press x, y, or z to scale it in only one axis
you need to do this for every part/material

make sure that there is nothing inside the mouth
combining all the models
once you are done aligning the uv map to the new combined texture and made sure that their uv maps have the same name, select all the objects and combine them. if everything worked correctly then their should only be one uvmap left and all the objects look correct using the same texture file.

where you can check the name of the uv map

triangulate the mesh
because triangles are the best shape for computers, payday will only except the model if it uses just triangles. its always a good idea to apply the triangulate modifier at some point.

merge by distance
sometimes the model comes with parts that are exactly on top of each other but not connected, this can cause the model to come apart when posing it. to fix this we have to merge by distance
press tab to switch to edit mode, press a to select all
importing base model
note, i took these screenshots before starting my project so you wont see my model in there but it should be
base model exporting
for this mod, you will need a base model, kentos model is generally used as the base for las mods and is what we will be using. you can get his model by going into the diesel bundle viewer and searching for "civ_male_des.model".
after you find him, you will want to import him into the model tool and export as fbx. MAKE SURE YOU KEEP THE ORIGINAL .MODEL FILE, store it in the same place as the exe for the model tool as it will be used later for importing your custom mod into payday.

import settings
when importing the kento fbx, you want to:
  • set scale to 100
  • manual orientation on
  • y forward
  • z up
  • turn those 2 options at the bottom of armature on
  • animation off

you now have to remove

and since we are doing the body and head as one, you will want to remove g_headObject

now move and resize your custom model until it is roughly the same size as the kento model, make sure that the feet, shoulders and head align as closely as possible. i also recommend you turn on "in front" for the bones view port display
don't worry about it bot being 100% aligned, we will be moving it later. however the less aligned it is, the more you will have to warp it which may cause it to look a bit off if done to much but it should be fine
rigging and weight painting
weights are what determine how much a bone controls the mesh and where, weight painting lets us change that

copy the original bone rig and align it to the custom model
now you will have to duplicate the base armature and pose it into the custom mesh
dont forget to apply the pose after you are done

parent bone to the mesh

remove unusable vertex groups
their are 6 (i think) bones that you cant use or else you will get an error in the model tool. those bones are
  • a_weapon_left_front_locator
  • a_weapon_right_front_locator
  • aim_locator
  • BackPack1_locator
  • e_taser_locator
  • eyeAim_locator
remove them the same way that i do

weight painting
to make the bones control the mesh, we need to parent it. their are 2 kinds of parenting that i will talk about, automatic weights and empty groups.
automatic will automatically paint weights which can save time however it tends to be messy and on some messy models, it is straight up garbage.
i recommend parenting with empties which will make it so that their is no weight and you have to paint it in yourself. just be warned that this is a lengthy process and the hands specifically take forever to do
ctrl+left click to switch bones in weight paint mode | ~ shows the menu that lets you view selected
i highly recommend that you do not spend too much time on this part because your first few times will be extremely challenging, but the more you do it the faster you will get. you can also use the base mesh as an example of what to do or watch youtube videos to help

limit weight to 3
a limitation of the diesel engine is that if the weights of more than 3 bones overlap in one area, then it will not work and you will get an error in the model tool. however their is an option to limit the weights to 3 automatically

move mesh into position
once you are done you will have to use the armature that you just rigged to move the custom model into the same position as the base. this is definitely the hardest part and you model WILL look weird. even as im making this guide my model looks strange. however the first time is always the hardest and it will always get easier as you make and learn more.

ignore the part where i split the view, its not necessary

congrats, all the hard parts are complete. now we just have to do a few more things which should be pretty easy compared to what you had to do before.
preparing for export
connect your object to the base armature
clear parent your model with keep transforms, then apply the armature modifier. after that, parent it to the original base rig with empty groups, it should keep all of its weights.

mark seems
in the uv editor, select all faces and press mark seems from island with mark sharp turned on. then apply the edge split modifier with edge angle turned off. finally you will want to smooth vertices with all faces selected. you will know if it worked by if the edges split open, however you have to set the smoothing to 0.

apply transformation
you have to apply transformation to the mesh(scale, rotation, position)

rename the object and mesh + remove material

rename the uv map to UV0
exporting model
make sure that you
  • apply all transformations
  • certain bones are removed from the vertex groups
  • mesh is triangulated
  • marked seems, edge split, and vertex smooth

export settings
y forward
z up
apply modifiers off

importing model into payday
how to turn this into a .model
so you have to go through this whole process in order to convert the model into something that payday can read.

first you will need a file called "model_script.mscript" that contains

<?xml version="1.0" ?>
<import file="my_model.fbx" type="fbx" create_objects="false"/>


have that sit in the same folder as the model parser

then you have to make sure that the kento model that you extracted from the start of the guide is in the same folder as the modelparser and model_script.

next you want rename your custom mod that you just exported out of blender and call it "my_model" and move it into the modelparser folder like the rest.

then you want to use command prompt and open it to that directory (as shown in the video) and paste this in
PD2ModelParser.exe --load "civ_male_des.model" --script "model_script.mscript" --save "my_model.model"

it should create a file called "my_model.model" which you will then put into the model parser and convert to obj and then back into a model. if you dont do that last part then the mesh will be all messed up in game
edit: you can actually do this with the gui, just place the mscript in the script and the base model in base model
making fps model
this is literally super easy because you just delete the body and export the arms only

edit: it may be easier to just select the arms and hands and then invert the selection and delete.
making the actual mod
las helper
i recommend using las helper for this part because it can save a lot of time.
first time using it, your anti-virus might mess up the file generation so you might have to run it again

old fashion way
you could also do the old classic of taking another persons mod as a base and replacing the names and stuff. you need to make sure that the main.xml file,.lua file, object and unit files, and material config all match up. if you make one mistake it wont show up in game.
how my mod turned out
you can see from these screenshots that the mod works, but there are some issue mainly the weight paint of the arms. however those could be easily fixed with some weight painting, but im tired rn and want to get this guide done.

Matcher Aug 3, 2022 @ 8:14pm 
what exactly would I need to change? seems simple from what you said
THOT_PATROLL  [author] Aug 3, 2022 @ 7:22pm 
you probably need to enable it in the .object file, if you could send the mod to my discord then i could probably do it for you. my discord it "McDonald's cup#4371"
Matcher Aug 3, 2022 @ 7:45am 
it worked but my character is headless when I put on the outfit. The head is part of the model file but the texture file for the head is separate, any way to fix it?
THOT_PATROLL  [author] Aug 2, 2022 @ 10:25am 
the "material" file is just the file that ends with .material_config, its what the game uses to basically choose what texture goes where and how to show it in game, you could just use the original one if you want
Matcher Aug 1, 2022 @ 8:54pm 
I don't have a material file, is that a problem?
THOT_PATROLL  [author] Aug 1, 2022 @ 3:49pm 
that should be pretty easy to do, just make the Las files and replace the stuff like textures and material config to the new one, but you will have to change some things like the file paths in the config and the textures in the main.xml
Matcher Jul 31, 2022 @ 11:45am 
could I pick an existing mod that changes the default outfit of a heister and turn that into a LAS skin easily?
deckenid Jul 18, 2022 @ 9:27am 
Thank so much for this!
THOT_PATROLL  [author] Jul 15, 2022 @ 8:15am 
you need to remove all vertex colors, in the same menu as the vertex groups and shape keys, their is something that says vertex colors and you have to delete anything in their, i will update the guide to include this later
xtremist ninja Jul 14, 2022 @ 7:34pm 
awesome guide. however i am getting an error when trying to convert the .fbx file back into a .model, after inputting the line into the command prompt, it spits out

Unhandled Exception: System.Exception: Error executing model script model_script.mscript: Vertex colour: only per-vertex colouring is supported

i have not touched the colouring on the model at all, is there a way around this?