A Detailed Guide on How to Create a SIMS 4 Cloth CC

Introduction

This is not a start to finish tutorial to make one particular cloth, instead more of a detailed workflow guide to complement whatever cloth CC tuts you're learning from right now.

If you have the basics on Blender, Marvelous Designer and 3D, it will help you a lot to comprehend many things. If you don't, I wish you good luck. Hopefully this guide shines more light on your path.

The required softwares for a making cloth CC:

1. Sims 4 Studio
   To create CC of SIMS 4.
2. Blender
   S4S only works with Blender ver 2.70-2.79b
3. Marvelous Designer
   The 3D software developed specifically for designing clothing.
4. Photoshop

Note of cautions:

1. Many S4S tutorials on Youtube are outdated. Thus, if available find the most current tutorials.
2. Start learning from making a top. A more complex cloth like a full body type will have more technical problem. It will just hinder your learning process.

Table of Contents

1. Create your cloth in Marvelous Designer (MD)

1.1 Download the SIMS 4 avatars for MD
1.2 Design your cloth
1.3 Retopologize your cloth mesh
1.4 Prepare your uv-map before exporting your cloth
1.5 Export both low poly and high poly mesh as .OBJ files and import it to Blender

2. Work on Blender

2.1. Choose your reference cloth from S4S, export it and append it to blender
2.2 Close all holes of your cloth
2.3 Transfer weight paint
2.4 Do vertex paint
2.5 Data Transfer uv_1 from the reference cloth to yours
2.6 Working on uv_0
2.7 Split Mesh don't just mark sharp
2.8 Texturing
2.9 Testing your diffuse map and normal map in Blender
2.10 Join the nude mesh from EA to Blender
2.11 Testing
2.12 Assign mesh geometry group to your cloth
2.13. Import your cloth to S4S
2.14 Creating LOD 1 2 3

1. Create your cloth in Marvelous Designer (MD)

MD allows you to make a 3D cloth as if you were sewing a real one.

Tutorial on how to use MD:MD official Youtube Channel. Different version of MD usually has changes on the UI so choose the most current tutorials if you can. 

To create a cloth you can do it on any 3D software though, Blender, Zbrush, MD, etc.

1.1 Download the SIMS 4 avatars for MD

Avatars are the mannequins to fit your cloth creation. Don't use MD default avatar. It won't fit to SIMS4 character. Download SIMS4 avatar here.

1.2 Design your cloth

You should start by making the easiest cloth. The top.

Tips: Having symmetrical mesh will make the control of your mesh easier and more predictable for later deformation and animation.

Note: When you create a pants, you need adjust the diameter of the bottom leg according to the size of your pants reference. If it's too small it may clip with shoes. TS4 developers already have certain size to ensure the pants diameter fit the shoes.

MD Tips:

1. How to Make 2D Patterns Transparent?
   For easier tracing

1.3 Retopologize your cloth mesh

Most tutorial out there skip this step. So you'll end up with a very high poly and polygons with wrong edge flows that ain't good for animation. But you can still use it for personal use though. It just takes more memory and calculation power and maybe some animation glitches.

If you want to do it the better way, retopologize your cloth. I prefer to do it on Blender 3.0 above, then I export it as obj to work further on Blender 2.79.
The reason to work on Blender 3.0 above, because there are add ons on higher version Blender making retopology easier.
The reason to export it as obj, because TS4 only work with Blender 2.79b and some lower version.  It can't open the files from higher version of Blender. But it can import obj.

You can do retopology on MD too if you will.

What is retopology?

Reconstructing your cloth mesh to become low poly. 

Why retopologize?
The topology created on MD is definitely high poly / high resolution. It's not good for the game. Higher poly means more calculation and cost the game engine. Thus, you retopologize - rearrange, reduce the number of polygons and recreate the edge flows of your mesh. 

Note: Retopology is a deep topic, thus you need to learn more about it from other resources.

Some tutorials:

1. Retopology A Detailed Guide - What is Retopology & Why Do We Need It?
   Grant Abbitt will explain and show you what is and how to do it in Blender.
2. Retopology for Beginners in Blender 2.8 - Retopo the Correct Way
   by FlippedNormal.
3. Marvelous Designer Retopology Tutorial
   This tutorial will show you how to retopologize in MD.

We retopologize in quads. Rectangle shape. The reason we human use quads, because it's easier to control and manage compare to tris (triangle).

Although in game, quads will be triangulated - turned to triangles or threes. Because a three only has 3 points, thus will always create a 2D triangle flat surface. It's easier to calculate for the engine. While a quads could potentially form a 3D shape, thus harder to calculate.

You can retopologize on MD or Blender. If you did it on Blender, you need to recreate again your uv map.

From retopologizing you'll have a low poly mesh. But keep  and export also the high poly. You can use the high poly for texturing later - baking a diffuse and normal map, so you can have the creases and folds of your cloth. 

I usually retopoligize on Blender 3.0 then I export the result to .Obj. So I can import it to Blender 2.79. Because Blender 2.79 can't open the Blender file from higher version. 

Tips:

If you do retopology on Blender there are useful add on that you should install or activate:

1. Edge Flow by Benjamin Saunder
   A free add on. To rearrange your vertices in good position.
2. Draw X-Ray by bartoszstyperek
   A free add on. No need to use the confusing "In Front" feature to see our topology faces anymore. That feature shows all the faces at the front and on the backside of our object. But this add on will hide everything on the back.
   It was made for Blender 2.8, but still working on Blender 3.0. For more detail watch this YouTube add on review.
   

   

3. Loop Tools
   Native add on to rearrange your vertices in good position.
4. F2
   Native add on to extends Blender native functionality of creating faces. It allows you to create a face from a single vertex selection or a single edge selection, while retaining all the built-in functionality.
5. Merge Tools by Andreas Strømberg
   Free add on that can combine vertices by click and drag instead of the default where you have to press M and then choose how you want to merge them.

Topology techniques

These are some topology techniques I've found on the internet and am using it.

1.4 Prepare your uv-map before exporting your cloth

Switch to uv editor

1) RMB-click in the window, choose Set uv from pattern alignment
2) then Fit uv to unified (0-1)

1.5 Export both low poly and high poly mesh as .OBJ files and import it to Blender

Why you need low and high poly mesh?

So you can bake details from high poly mesh to low poly.

If you retopologized on MD, export the low poly and also the high poly as .obj. Then import both to Blender.

If you retopologized on Blender, then just export the high poly from MD, the low poly from Blender and import both to Blender 2.79b.

When you export, a pop up window will appear. This is the export settings.

Thick = export include thickness of the garment. You'll have two layers of a surface. (Not necessary)

Thin = export without thickness.

2. Work on Blender

I assume now you have the low poly mesh of your cloth in blender. Either from MD or from Blender. Because this is the mesh that you're going to work on.

2.1. Choose your reference cloth from S4S, export it and append it to blender

You get your reference by exporting one from S4S

Why use a reference?

To transfer its:

1. uv_1 (it's a uv map for deformation not texturing).
2. weight paint.

How to choose a reference?

The better its shape looks like yours, the better. Pay attention on the thickness and length, for example:

1. If your sleeves are thicker/bigger than your reference.
   Potential problem: The weight transfer from your reference could miss some area, usually near the armpits.
   Solution: You could make your sleeves thinner to the same size as your reference, or if you insist you can work on the weight later on.
2. Your skirt is tight, your reference's is puffier.
   Potential problem: You skirt could receive the weight data from your reference legs, instead of the reference's skirt around the bottom area, because the reference's legs are nearer to your skirt than the skirt.
   Solution: Find reference with tight skirt.
3. Your skirt is longer than the reference.
   Potential problem: The bottom skirt could get weight data from the reference legs, which may cause issues.
   Solution: Find a reference that has the same or a bit longer skirt length.

Tips:

1. It's possible when making full body cloth, you can't get an ideal full body reference for weight transfer.
   Usually the problem lies above the waist area and below the waist area.
   Then you could separate half of your full body garment into top and bottom, and use a top and a bottom as reference for each.
2. You don't have to use the same reference for both uv_1 and weights.
   In certain situation, sometimes your reference isn't ideal for uv_1 transfer, such as a lot of edge splits, causing the result of your uv_1 is ripped here and there and if merging them is too much headache.
   You could just find another more suitable reference just for the uv_1.

Do:

1. Find TS4 design that match the closest to your design.
2. Export the mesh from S4S. Export the LOD 0 mesh - The highest quality mesh that has the highest number of polygons.
3. Append it to blender. When you double click a blend file, you'll see more folders. Open the "Object" folder
4. Select only the files the begins with S4s4studio_mesh_
   such as s4studio_mesh_1, s4studio_mesh_2, etc.
5. On the right Outliner Panel, combine all the s4studio_mesh_ (if there are more than one), by pressing CTRL + J (Your selector must be on 3D View Port)
   Rename the object name to "reference"
   Delete any extra "rig" and "bone_bone_shape" coming from the appending.

What is a clone?

A clone is different from a reference. A clone is a cloth that are going to be replaced through importing your cloth to S4S. A reference is a cloth you export from S4S to get its weight and uv_1.

What is LOD 0, LOD 1, LOD 3?

The higher the number the lower the number of polygons or detail of the mesh. EA use different quality of meshes, depending on the distance of your view in the game. The closer, the higher quality mesh it uses, vice versa.

What is uv_0 and uv_1?
As a beginner you learned that uv_map is for texturing - in Sims4 they name it, uv_0.
But a uv_map can also be used for other things, such as for mesh morphing in the game, EA named it, uv_1. It utilizes a map called a deformation map or dmap. And vertex paint is used to dictate what variation of dmap the area will morph according to.

However, there is a limit to how far the dmap can push the geometry out or inward and how mobile(up and down) it can be, which posed a problem with breasts to ts4 developers (and eyes, nose, mouth ), so they decided to handle it through bones.
The bones responsible for morphing are always called like b__CAS_(the area of the face or the body)__. Any other bone is responsible for the movements only.

Every SIMS 4 cloth has uv_0 and uv_1 map. You may use a third or fourth uv_map for texturing and baking purposes. But remeber those extras must be removed before importing to S4S. Else they will create deformation problem.

2.2 Close all holes of your cloth

For example the arms, skirt, neck, etc.

2.3 Transfer weight paint

Basically, weight paint is a system to assign a value based on a cold-hot color system to each vertex. Blue is the lowest, red, the highest.

In SIMS 4 it's used to determine the deformation level of certain part of the mesh in accordance to the bone movement. 

Why we transfer weight paint from the reference?

So we don't have to weigh paint ourselves. After the transfer you may need to adjust it / paint it by yourself a little bit. The more suitable your reference is, the less fix is needed.

Here's the color guide.

Do:

1. First select select your reference cloth - the source of your weight, then your cloth
2. Go to Weight Paint mode
3. Follow the instruction in this pic.

Clean: to remove from each vertex, vertex groups that have value less than the set value.

Limit total: to limit the max number of vertex groups that a vertex can have. For example after the transfer, a vertex could have 10 vertex groups, after hitting the "Limit Total" button, the number will be reduced.

How to check that the weight transfer has happened?

One way to check it is by going to Vertex Tab. Look at the vertex groups. Before, it's empty, after the transfer you'll see the list of vertex groups.

In the weight paint mode, if you clicked on some of the bones, you'll see your cloth that's in blue, some of them will have some yellow-red color. 

How to test the weigh paint result

1. Make sure your cloth object is selected.
2. Add an Armature Modifier
3. Select source : Rig
4. Run an animation.
   This is the best way to test the result of your weight paint without having to back and forth into the game.
   How to do it?
   Watch this video starting from 1:52, you can find how to export an animation and get it in blender.
   https://www.youtube.com/watch?v=KNnlkANV9AM&t=112s

I usually use the normal walk and creepy walk. The creepy walk I used to see how the colar looks like when shrugging.

Note: You may one day wondering like I did, why there are bones sitting on the same spot, such as:

1. b__L_ShoulderTwist__ and b__L_UpperArm_
2. b__L_Skirt__, b__L_Thigh__, b__L_ThighTwist__

The only answer I can get skirts of different length and shape are rigged differently. Some of them have no skirt bones, others have no thigh bones, third have all three. It all depends on what gave the developers the best result during animating.

Note:
b__CAS_L_Breast__
b__CAS_R_Breast__

The weight paint on these bones will make your mesh get deformed according to slider. The more weight you put on them, the bigger the breast will be.

2.4 Do vertex paint

Explanation:
Vertex paint is used to dictate what variation of dmap the area will morph according to.

The variant controlled by different colors:

1. #00ff00
   The morph will follow the shape of the body. For example: the top
2. #3fff00
   The morph won't follow the shape of the body. For example: for a not tight skin skirt.
3. #007F00
   The color for accessories
4. #007F3F
   The color for areas that need to be affected by facial sliders (ex: a hijab near face area). Basically hairlines, facial hair, piercing, the roots of eyelashes are painted with it in the area where they touch the skin.

Do:

1. Make sure you're in the Solid Viewport Shading. If not, you can't see the color of the vertex on your cloth object.
2. Select your cloth mesh.
3. Go to Vertex Paint Mode.
4. Change the color to 00ff00
5. Click the paint button > Set vertex colors

Explanation:

To color only certain area, you can select the faces on edit mode and get back to vertex paint mode, and click the face selection masking for painting button (near the layer).

To see the color vertex in real color, use the Viewport shading - Bounding Box. This you can use the color picker and get the correct color.

2.5 Data Transfer uv_1 from the reference cloth to yours

Do:

1. Select your cloth object.
2. Go to Vertex Tab
3. Rename existing uv_map to uv_0
4. Add new uv map. Name it, uv_1
5. Make sure to remove double and clean up - Mesh > clean up > data loose.
   It will mess up your data transfer
6. If your reference have splits, you need to merge them. Except for the area where there are seams.
   If you don't merge the splits, your uv_1 will be ripped at certain part, and could potentially cause a problem up to certain extend.
   But usually area around the sleeves can't be merged without messing up the result. So just let it be.
   Tips: To find split edges on the reference: Press Spacebar > Select Non Manifold
7. Do the steps showed on the image

Explanation:
When you create a new uv_1 map, this act as a "container" to receive the uv_1 map transfer from your reference.
Remember, the naming has to be in lower case or it won't work. 

For better understanding you may watch this YouTube tutorial:
Transferring and Editing a Uv_1 Map in Blender 2.78 by Mauve Morn.

Explanation:
On that video, the reason Mauve Morn tell you to make the seam of your cloth on the side of the body align with the seam of the nude mesh is in order to get a good result of uv_1 map. The closer yours seam to EA design, the better the result.

But in my experience the seam of TS4 cloths don't always follow the nude seam. So it would be best to follow the seam of your reference instead.

2.6 Working on uv_0

Before the next steps Texturing and Baking you need to prepare uv_0 map.

Create seams on your mesh and unwrap them. How to seam your mesh, look at your reference as an example. This tutorial won't explain how to create/ prepare your seam. You need to watch Youtube videos explaining the stuff.

This image is the standard layout map to lay your uv islands out.

Here are the things you need to know about laying out your uv islands:

1. Lay your uv islands of your cloth on the correct areas.
2. If you put it incorrectly, for example you put top garment uv islands one on the accessories area, your garment will project images of the accessories you wear on the CAS, and vice versa.
3. The neck, arms, legs, feet need to be located as default location.
   The rest, you can put it anywhere inside each desginated boundary.
4. The bigger the uv island, the more details you'll get.
5. Scale the islands altogether to get the same quality texture result.
6. For less important part like garment holes you can resize it smaller. But for important part like the cloth itself make it big as possible. To get a better quality texture.
7. Don't rotate your uv island as you will. Use 45, 90, 180, 270 degree rotation.

2.7 Split Mesh don't just mark sharp

In the game if you want to have sharp edges, you can't do it by marking sharp, it doesn't translate into the game. Instead you must split them.

The efficient way to do it is to mark them sharp, then use Edge Split Modifier to split all of them at once.

Do:

1. Tick only the Sharp Edges box.
2. Click apply.

Dark shadows

When two edges connect at an angle that is close or below 90 degree, they'll create a dark shadow on the face of the mesh. If you wan't t get rid fo them, split them too.

Dont use auto smooth

It has no use in the game.

2.8 Texturing

This guide assumes you know how to assign materials and play with nodes to give your cloth texture. What this section teach you is how to bake the texture to create maps.

Baking is the process to create a 2D image / a map from the appearance of your cloth.

There are different kind of maps compositing your CC. TS4 uses:

1. Diffuse map
2. Shadow map
3. Specular map
4. Normal map
5. Emission map

You don't need to make them all (be my guess if you want to), just create these two are enough:

1. Diffuse map
   The base colors of your mesh.
2. Normal map
   To make your cloth have bumpiness, such as: creases.

At this step your uv_0 must be ready.
Don't join the nude mesh yet.
Make sure your high poly mesh is in Blender, if not import it.

Do:

1. Change Blender engine to Cycles.
2. Change the world background on Node Editor to white.
   This way you don't need to bother with lights. But you could setup your own lights if you will.

Diffuse map

To create details such as the creases. We use high poly mesh details and bake itu to your low poly mesh.

Note:

Before start baking make sure to:

1. Select the uv_0 uv map. Or else you'll end up baking on a different uv map.
2. On UV/Image Editor, create New Image 1024 x 2048, with Alpha. Name it whatever you want. Let's say Untitled.
   This will be the containter of your baking result.
   Note: Blender bake results hard edges, which often makes the texture not smooth on edges. Here's the workaround, create New Image twice as size, 2048 x 4096. Then resize it on Photoshop. This is a lot easier than manually smudge the edges.
3. Activate the nodes on each materials you use.
   Cllick on material Tab > Surface > Tick the box Use Nodes.
4. Open your Node Editor.
5. On the Node Editor create an Image Texture Node and choose the Untitled Images. It doesn't connect to anything
6. On the Node Editor create an UV Map Node and choose uv_0 and connect it to Vector of the Image Texture Node.
7. Repeat th 5-6 steps on all your materials you use.
8. Make sure that you select each Image Texture Node in every material.
9. Disable the camera / render icon of all objects except your cloth, including your high poly, else it may create blacks on the baking result. Example of failed bake: https://prnt.sc/26hkigd
10. Make sure your high poly and low poly are visible.

Baking

Do:

1. Go to Render Tab > Sampling
   Change render samples to : 50 for testing.
   If the result is ok, up the number to eliminate noise.
   Higher render samples takes longer to  bake.
2. Select you high poly, shift select your low poly
3. Choose the type of bake : Diffuse Map.
4. Tick the selected to active
5. Click bake.
6. If the result is ok, increase the render samples to above 1000, you can always increase or decrease to your liking.
7. Bake again.
8. If the bake is succesful, you should see on UV Image Editor the bake result.
9. Save the image.

Tips: If the bake result is dissapearing to something else, probably because there are one or two of you materials, you select different image texture node, not the one you intended to do the bake onto. The solution just select the Untitled image on the uv/image editor.

Normal map

This map will create depth of your texture.

The steps are the same with creating a diffuse map, but you choose the bake type to normal map.

After you get the result, read this tutorial: https://theslyd.tumblr.com/post/161020478636/tutorial-normal-bump-map-baking-in-blender
to create the type of normal map needed by TS4.

Remember the normal map is in 1024x1024px size.

To save normal map in .DDS you'll need to download a Nvidia Texture Tools Exporter.

Download the Adobe Photoshop Plugin. Later, everytime you save your normal in DDS, a pop up window will appear. Choose BC3 and save.

2.9 Testing your diffuse map and normal map in Blender

Create a new material using the diffuse map and normal map and assign it to all the faces. 

Makes sure the image texture for your normal map - space color should be Non-Color data. Else you'll get weird result.

Extra: How to add a logo to a material.

This is if you wanted to add a logo to your material.

Note: If you want your logo to be sharper - higher quality, separate the area surrounding your logo by creating seams and unwrap it.

1. Select uv_0
2. Click the + button. This will duplicate the uv_0.
3. Rename the UVmap (or leave it)
4. Select all the uv islands and put it outside the uv area.
5. Create New image
6. Name it "MyLogo"
7. Size 1024 x 2048
8. Thick Alpha
9. OK
   

   

10. After the image is created, move back in only the islands where your logo will be on.
11. Export the uv layout: UVs > Export UV Layout
12. Name it : logo_uv_layout.PNG
13. Open Photoshop, open the logo_uv_layout.
14. Add your logo images.
15. Arrange the position of logos according to the logo_uv_layout
16. When is done. Hide the logo_uv_layou.
17. Save the image as logo_layout.PNG,
18. Back to blender.
19. Click on your material
20. Open node edtior
21. Add UV Map Node > choose your uv_map
22. Add Image Texture Node > Open your logo_layout.PNG
23. Connect both of them.
24. Add RGB Mixer Node
25. Connect.
    

    

2.10 Join the nude mesh from EA to Blender

Do:

1. Export the nude mesh from S4S. Use male or female, adult, kid, or infant nude mesh in accordance to your design intended to.
2. Import the nude to Blender.
   File > Append
   select your nude blender file.
   Open "Object" Folder.
3. Choose the file:
   1. bottom, bottom_2, bottom_2_3
   2. head, head_2
   3. teeth
   4. top
4. Delete  bone_bone_shape.001
   1. Delete unused vertices under your cloth then join the mesh with your cloth. Look at your reference as an example.
      Use this addon to remove it.
5. Join them with your cloth

2.11 Testing

This is an important step. Test your work.

Some cloth are divided into mesh groups. Some aren't.

If your cloth is just one meshgroup only, like a top, then you can import it to S4S and test it.

But if you make a full body cloth with many meshgroups, it's better test your mesh, how it functions in the game before split it. It will safe your time.

Because if you split it first, then there were problem, you had to combine all of them again, removed doubles, split it again and so on.

For male cloth I use the female swimsuit in male category. It has only one meshgroup. Although there will be problem on the foot, but ignore it.
For female cloth I haven't find one.

Make sure:

1. Remove doubles from your mesh
2. Clean it up of flying vertices / edges
   On Edit Mode
   Do: Mesh > Clean up > Delete Loose

Import your Blend file. Read another tutorial on how to import Blend file to S4S.

Some problems that often occurred to me

1. Little gaps on the meshgroup parts. prnt.sc/26n7lru
   1. It could be weight paint problem.
   Possible solution:
   Rejoin the meshgroups, remove doubles, weight transfer, split them again.
   2. It could be uv_1 problem.
   Your reference has edge splits on the problematic area.
   Possible solution: Merge the splits of your reference on the area where the problem occur. Then retransfer uv_1.
   Note: Not all splits on the reference can be merged without causing issue on uv_1.
   Tips: You could find another reference that doesn't have too much splits .

2. Mesh get distorted.
   Such as, the finger becomes spikey, the body flying all over the place.
   Possible solution: rework your weight transfer.
3. Mesh looks strange when you use the slider on CAS, like some parts just stay the same, while the rest gets affected.
   Possible solutions: Make sure to delete any uv map other than uv_0 and uv_1.
   I often use extra uv map for texturing purpose.
4. Skirt near the calf looks jaggy from front view.
   It could be the vertex paint. 00ff00 will make your cloth follow the shape/width of the body. In this case the calf. 3fff00 will make your cloth keeps your original shape and get bigger and small proportionally, ignoring the shape/width of the body. Some part needs to follow the shape of the body, some area don't.
   Possible solutions: Paint the right color for the area.

2.12 Assign mesh geometry group to your cloth

If your cloth works fine and need to be split into meshgroups, now it's time.

When you append your cloth reference, you select object that has the name: S4s4studio_mesh_ followed by number.

Each of those seperated objects represent a meshgroup. Each group has different geometry number .

You can check the number of each of them on the Scene Tab > S4Studi0 CAS Tools.

Now, your job is to dissect your cloth into several mesh groups and assign the geometry number just like your the cloth you're going to clone.

The position doesn't have to exact, except for the pants and legs.

The easiest way to seperate them is by selecting the vertices, then use P to separate them into another object.

If your clone have meshgroups, and you don't do this you can't import your cloth to S4S.

If the cloned cloth is separated into 8 parts, then your cloth also has to have 8 parts.

The naming of the parts doesn't have to be the same as SIMS 4. 

2.13. Import your cloth to S4S

Make sure all your cloth objects and rig are visible.

Use the rig that comes from the nude file, not from the reference.

2.14 Creating LOD 1 2 3

All S4S tutorials teach you to use decimate modifier to reduce the polycount. This will do the job with the expense of ruining your topology. If you create this cloth for your personal use, it's not much of a big deal, since LOD 1 2 3 used when the view is very far, noone will probably notice it. But if you want perfection, that means you have to reduce your polycont manually which will take more time.

Download the top and bottom part of the LOD 1 2 3 here. That way you can save time and it will be a perfect fit for the head and the leg S4S of LOD 123.