Tip& Tutorial by Adolf Navarro
Use 3ds Max, 3D-Coat, Character Creator and iClone to improve your characters
PBR materials give an extra realism aspect to your models. Here, I will show you a pipeline to create a human character and all their clothes texturized using PBR materials. The goal is to obtain a very realistic model of a clothed soldier while keeping a reasonable number of polygons, making it available to fast render animations or video games.
I’m not going to go into too much detail about each step as I am limited by the length of this article. Instead, I will concentrate on showing the relationship between the applications involved and the tasks developed with each one rather than going into great detail on each of the steps taken to create a character.
Character Creator is a powerful tool that allows you to design any human character in a matter of minutes. Any character’s shape can be set just using sliders or dragging the mouse, while the skin and appearance attributes can be set using its dynamic materials. The character obtained is fully rigged and can be exported to a modeling application like 3ds Max, where you can model their clothes. Then, you can skin the cloth meshes to the character’s body and re-import the clothed character to Character Creator.
Character Creator allows multiple cloth layers, so the clothes skinned in 3ds Max can be stored individually and used in different combinations on the original character or in any other character that you can create.
Character Creator will automatically conform the clothes to the shapes of the different characters that you use, and these characters can be exported fully rigged and clothed to any animation app or to game engines like Unity or Unreal in order to be used in video games.
Character Creator allows PBR textures providing extra quality and realism. In order to create the PBR maps, I’ll show you how to export the clothes created in 3ds Max to 3D-Coat, where you can paint the clothes assigning realistic textures. 3D-Coat will create the normal maps with all the details for the low-poly models. As it is not necessary to create hi-res models to achieve this goal, the character creation process is speeded up and simplified.
The texture maps created in 3D-Coat can be used for the clothes imported into Character Creator from 3ds Max, giving them an extremely realistic appearance.
Step 01 – Making the character in Character Creator
Character Creator uses a template base character that allows you to develop any male or female character, just by selecting body parts and using the associated sliders to modify its shape. You can also drag the mouse over any part of the character while pressing the left button to change its aspect. The use of dynamic materials allows you to set the skin color for your character, as well as other characteristics like age, facial and body hair, freckles, cosmetics, tattoos or scars. Again, just use the sliders associated with each feature.
Step 02 – Modelling the clothes and accessories in 3ds Max
I used 3ds Max, but you can use other modeling tools like Blender, Maya, Cinema 4D or Lightwave. The app that you use has to be able to skin the clothes over the rigged character and export them in FBX format. I used the rigged character exported from Character Creator as a base to model the clothes over its shape. Character Creator and iClone accept multi-layer clothing, so I modeled every garment individually. In this way, I can make any cloth combination later. I always kept a reasonable number of polygons, bearing in mind that this model is going to be animated in real time. Step by step, you can create a collection of clothes and accessories that fit over this character’s shape. The good thing is that, when re-imported into Character Creator, the clothes will be conformed automatically over any other character’s shape.
Step 03 – Skinning the clothes on the character and tuning the envelopes
After the modeled clothes have been skinned to the body shape, I recommend tuning up the resulting envelopes using the animation embedded in the FBX file exported from Character Creator. The envelopes define how the bones deform the skinned items when the character moves. A wrong configuration results in awkward deformations in the cloth shapes and textures, so it’s quite important to spend time checking how the clothes react under extreme poses, relaxing the bone’s influence when it derives in exaggerated deformations. Also, elements like holsters or backpacks have to follow the body in a more rigid way, avoiding unnatural bending.
Step 04 – Creating the UV Maps for the clothes and accessories
Before starting to paint the clothes, you must create their UV maps. 3ds Max has the Unwrap UVW modifier to do that. You must define the seams in the elements in order to create projections of the 3D models over a flat surface. You must ensure that the flat texture image that you will paint with 3D-Coat will fit properly when applied and conformed over the cloth model. This can easily be checked using the chessboard checker pattern included in the 3ds Max modifier.
Step 05 – Painting the clothes and accessories in 3D-Coat
Once the clothes have been skinned to the character and have a proper UV map, they can be exported one by one to 3D-Coat in FBX or OBJ format. 3D-Coat will load the file, asking us for the resolution that you expect for the texture maps that are going to be created. The bigger the resolution, the more quality you’ll get, but the heavier your model will be, so it’s important to achieve a compromise. Maps of 2048 x 2048 pixels provide a pretty good resolution without overloading the model. Nevertheless, you can later reduce some of the unnecessarily large maps like ambient occlusion or metalness.
Step 06 – Re-importing the clothed character in Character Creator and assigning the texture maps
Once the painting process has created the texture maps, you can proceed to export the character with the skinned clothes from 3ds Max and re-import the file in Character Creator. If all has been done properly, Character Creator will recognize the cloth shapes and will ask for a level to each one of the pieces attached. The clothes will come with the plain textures defined in 3ds Max, but you can turn them white and assign the texture maps you have created with 3D-Coat. Once the cloth shows all its colors and textures it can be stored attached to the character or alone, ready to be used for other characters.
Tip: Attaching rigid accessories to the character
Accessories like guns or helmet gadgets are not clothes and don’t have to be imported into Character Creator. These items are created in 3ds Max and we only had to follow steps 4 and 5 in order to make their UV maps and paint them in 3D-Coat. However, to import FBX files into iClone you’ll need 3DXchange, an app provided by Reallusion that makes the conversion to iClone’s prop format. Once imported into iClone, the accessories can be attached to the character and it can be animated or exported to any 3D application or game engine.