Introduction to Rigging: Planning Your Rig by Luis San Juan Pallares
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Welcome to this Introduction to Rigging tutorial series for Max. These tutorials are aimed for Max users that want to get proficiency in rigging, so basic notions of navigation and basic use of the software will not be explained. The objective of this series for beginners is to get you comfortable with rigging and the tools Max has to do this task. This tutorial will make you familiar with the concept of rigging and will show you how to optimize your work, to solve problems, to create good control for the animators and have good deformations on the mesh. The goal of this tutorial is to get your rigging skill to a professional level and be able to work as a rigging artist.
We will have a brief explanation and samples of Maxscript in the next chapters. Maxscript is the script language of Max, and you will use it to code. Code can sound scary but it will do Max perform tasks for you, and will make your life much easier and speed up your way of working. Maxscript is a really powerful tool that will allow us to optimize all the repetitive tasks. Through simple examples, you will get confidence with it and see all the potential you can achieve when you keep using it in your future rigs in a daily basis.
The concepts we need to know before approaching a rig will be defined in this chapter. We will also see how to face the task of creating a rig. We will speak about working in a professional environment and the issues that usually arise when working as a rigger at a studio.
Planning and Reference
Before starting any new rig for any type of character, it is important to get references, it doesn't matter the kind of character or creature we want to rig. Before we even start Max, we should look at references. Internet and drawing books are great tools to get info.
It's a good practice to find references for these items: controls, bones, deformations and facial expressions.
Control for a rig is the control you will give the animators to animate a character. I recommend looking at the work of other rigging artists, not only people that use 3ds Max but any other application. At the end of the day almost everything can be translated to other software, the important thing is the concept.
There are a lot of forums to help you get inspired and a lot of demo reels that show how other people rig their work. And there are a few available free rigs that you can download and play with to decide what you like or dislike about them.
Try to save and categorize all the reels and demo rigs you find on internet. This is normally quite helpful when you want to start a new character; seeing other people approach is always inspiring.
We need references to help us to decide where to place the bones in our 3D mesh. Use any search engine and look for references for the skeleton of the character you want to rig. This will help to decide where to place the bones in our 3D package.
You don't have to recreate exactly the same amount of bones as the real skeleton.
For example, a vertebral spine has 38 or 39 elements and when we translate this to a 3D rig, we will use between 3 and 8 bones only, enough to achieve good deformations. Something similar happens with a human hand: it has 27 bones and we will use 15 for our rig.
It's always good to search for videos before starting your rig; Sites such as Youtube or Framepool will help you very much. Remember to be specific in your search, like adding the specific area of the body you want to focus on, for instance: hand, shoulder. Use two different types of movement and action in the search. This can help you to see de deformation of each body area, for example: running, walking, jumping.
Drawing books are another great source of inspiration, for both humans and animals. The explanation of how to paint a human or animal in different poses and how the shapes change can be easily translated to 3D. If you are working on a human character, your own body and a mirror will be your easiest reference.
Facial Expressions Reference
The way a person shows feelings (such as happiness, sadness, anger) is mainly by facial expressions.
The other way of transmitting feelings is the body language, but this is a job for animators. As a rigger, you will have to provide them with the tool to achieve what they need, so study the facial expression and make a face rig that can provide what animators want is necessary for a good rig.
Internet is again a great source. For cartoony characters, 2D animation and concept artist facial expressions drawings are always the best choice (Fig.01 and Fig.02).
In a professional environment you are always asked how long it will take you to rig a character. This is always difficult to know, and it is quite normal to be over-positive and think that a rig will be easier and quicker to do than it turns out to. Be careful with this, it is better to be realistic and get the job done in time than promising a quick job and then being late. Your supervisor will prefer a realistic time and this will help to schedule the work properly. A good start is a To Do List. Write down all the tasks you need to complete the rig, together with an estimated time for each task. If you want to investigate or do a bit of R&D; for a certain part of your rig, write it down too. Please bear in mind that not everything will go perfect from the first time and you will probably have to do changes, so adding some extra time for potential problems is always a good idea. The experience is an advantage - if you had to rig a similar character in the past, you will know how to approach it properly and be faster the second time.
Normally the time you get to do a character is limited. Distinguish between primary and secondary tasks. Primary tasks will be the ones you have to get done in order to have a rig ready for the animators. Secondary ones will be those that will make the animators' work better or get a nicer deformation but are not essential; if they are not included in the rig, the animation can still be done. If you manage to get all the primary tasks of the rig done and still have a bit of time left, you can go for the secondary tasks that will be a good plus to your already good rig. But having all the primary tasks done will ensure animators can do their job (Fig.03).
Working with other artists
In a professional environment riggers are always working with other artists. As a rigging artist you will be involved with other disciplines - modellers, texture artists and animators. You will have to work together with modellers that will provide the mesh to begin your rigging with. It is always good practice to review the meshes with them to be sure they will achieve good deformations. Experience will allow you to know when a mesh is good or is bad and what makes a mesh deform well or not.
The technical word for a mesh that does good deformation is topology and you can search on internet to find samples or discussions about it. My opinion of what a perfect topology is has changed during my professional career, it is a debatable subject. You will have to ask the modeller to put the character in a certain pose that will make the rig much easier. The T pose is one of the most commonly used (Fig.04).
Modellers must be sure that all the objects they have created will match a series of technical checks that will allow you to rig a mesh without problems.
Animators will be the final users of your rig, so it is a good practice to keep a constant feedback with them. Asking them what they like or dislike about your rig will be always positive. Be ready to get critics to your work and be open to suggestions. At the end of the day the animator is going to spend all his working time with the rigs you created. And the suggestions they give can improve you rig and the final result.
Once you finish the rig and set the characters in different poses, it is a good idea to do a few renders in collaboration with the texture artist in order to check if the textures don't stretch or hold nice each pose. In quite a lot of cases the texture artists have to retouch their UV's or textures to make the character work nicely in all the poses.
When you work as a rigger, it is important to be organized. You will not be the final user of the rig, animators will use your rig and lighters will have your rig in their lighting scene.
Naming is a good way to distinguish objects and to know what object is for. It will be difficult to know what each object does if things are not named properly when you go back to an old rig. That is why naming each object is a must in rigging. Well used names are a powerful way of organizing things inside your Max scene. I recommend starting all the names of the objects for a character with the name of the character followed by underscore "_" For example: all the objects in our rigs will start with "Alien_" I get a really quick way of selecting the hole rig for that character when I select the objects with "character_*" Fig.05
This is the rule to name objects:
Character's name + "_" + Side + "_" + Part + "__" +Type of object and Kind of object
Side: to define what side of the character we are working on. It is only a capital letter:
_L_ left side of the rig
_R_ right side of the rig
_C_ no side, when an object is in the centre of the rig.
Part: specific part of the rig
Type of object and Kind of object: combination of two capital letters. The first letter will be the type of object and the second one the kind of the object.
First letter - type of object:
M mesh object
S shapes object
B bone object
D dummy or helper object
P proxy object we create for quick rigs
W object that will apply to another object as world spaces modifier (such as FDD, bend, etc)
Second letter - kind of object:
A objects to animate
H hidden objects we don't want to see on the viewport
F objects we don't want to select and will be frozen
Alien_L_eye__MF Alien character, left side, eye part and object mesh and kind freezable.
Alien_C_pelvis__BH Alien character, centre, pelvis part, object bone and kind hidden.
Please note the two underscores "__" before the Type of object and Kind of object.
This symbol __ will help us to separate the properties from the rest of the name.
By using "*__MF" in the selection floater, it will select quickly all the meshes and freezable objects in the scene.
By using "*__SA" the selections will be all the shapes and animation object in the scene.
Tip: Having "_SK_" in all the objects that will be part of the skin is a quick way to select them when applying skin modifier.
Tip: Max allows you to have names with spaces but I recommend using names without spaces. One easy reason is that if you double click on an object's name it will select the full name, but it won't if the name has got spaces.
Compare these two names: "test_arm_control_move" and "test arm control move"
If you double click on the first one, you will select the whole name. But if you click on the second name, you will only choose a part of it and you will have to select the full name by selecting manually. This sounds trivial but when you copy and paste a lot of names, it saves a lot of time (Fig.06).
Also, other 3D applications don't use spaces. If you want to export objects back and forward between two applications, you will have issues.
Tip: Max allows two objects to share the same name. This can cause trouble when loading and saving animations or when selecting objects. Checking you don't have duplicate names is a must for a good rig.
Naming layers properly will make a scene easier to manipulate. The best way to manage a lot of objects is having them in layers. Normal tasks as hide, freeze and select are much quicker if the scene is organized in layers. I recommend starting all the layers for a character with the name of the character. This will make the layers to stay together as we get more layers for other objects. Normally you will only work with the rig in your Max scene, but as soon as the animators put it in a scene for a shot they will have more layers in their scene for other characters, background... (Fig.07)
Apart from naming the layers with the name of the character, it is also good to have a second name to describe what is inside the layer. Use an underscore "_" for the space between the main name and the description of the layer.
Here is the rule to name layers:
_mesh: for all the meshes of the characters and object we want to see on the render.
_hidden: for all the objects we need to get the rig working but we don't want people to manipulate or use.
_control: for all the objects the animators will use to create their animation. Basically all the objects the animators will add keys to.
_proxy: a low res version of the characters quicker that the layers mesh, normally a sliced version of the character linked to be bones. Animators will have a quick rig for blocking their animation.
We must be sure that every object we create in Max is in one of these layers and none of the objects is in the layer 0.
Rigging is a technical process where you have to take a lot of things into account. It is very difficult to remember to check everything, so using a checklist is the best way. A checklist is usually a word document or excel file where you include all the things you need to check once you finish your rig. You will find a few checklists in the next chapters.
Similar Type of Objects for the Control Objects of a Rig
It is a quite extended practice to use the same type of object for the controls, the objects the animator will use to move the rig. The reason for this common practice is that Max has a selection filter that allows you to select the object of a certain type making the animators' life easier and avoids selecting objects by mistake.
The most frequently used types of objects for controllers are splines, as we can make our custom shapes for each control. In this tutorial we will always use splines as our control objects for the rigs (Fig.08).
Versions of Rigs
A rig usually has several versions. You will need to add changes to the rig that the animator requested or update the rig with improvements. To update the rig we use the Max tool for saving and loading animation.
Tip: It is a good practice to change the colour of the main control each time we do a new version. This way it will be easier to check that every scene has the latest version of the rig.
Tip: Don't allow anyone to merge or use the files you use to create the rig. It is good to have a separate folder with the final version of the rigs. Always include the version in the name of the file.
If you don't follow this system, you could find that an animator merged the rig from a file when you where working on it and hadn't finished the rig yet.
Alien_rig_V1 for the first version
Alien_rig_V2 for the second one, etc.
Animation Rig and Deformation Rig
There are two main types of rigs - animation and deformation. Animation rig is the rig we riggers create and animators use to animate. Deformation rig is the rig that allows the mesh of the character to deform and helps to create the deformation in a nice way. We use the deformation rig combined with the skin modifier to deform the character in Max. Trying to do the animation rig and the deformation rig at the same time is a bad approach. Always start with the animation rig. We will not move to the deformation rig until we are sure that we have achieved what we need on the animation rig. The deformation rig will always be working on top of the animation rig.
In the following chapters, firstly we will create the animation rig for each body part and then we will continue with the deformation rig (Fig.09 and Fig.10).
Tip: In busy projects, you can start giving the animator an animation rig with the proxy geometry. This rig will be quick and will allow the animator to start blocking their shot. The proxy mesh will give us a rough idea of how the final mesh would look. Later on, you can load the animation to a rig with the deformation rig, so the animator will be able to see if the character with the mesh is deforming properly. By doing this, animators can start working earlier in a shot and take pressure off of you (Fig.11).
The main body part or areas we are going to divide the rig into are: spine, neck and head, eyes, legs, arms and hands.
We will develop the animation rig first and later the deformation rig for each area. In the next tutorials when we develop each rig area and explain it properly in detail, we will speak first about the placement of the bones and after about the angles of rotation for each bone and how many controls we will need to animate each area nicely, and last about the deformation rig and how to get nice deformations. Fig.12 and Fig.13
Tip: Good practice is to take screenshots from your model and draw over them. Try to figure out the ideal location of the bones and where to place the controls. Don't worry about deciding it right now; we will see how many controls are needed and where to place the joints in the next chapters.
You have seen the FK and IK words in previous images. FK and IK are two ways of controlling a chain of bones.
FK is the shortening of forward kinematics; meaning that we rotate each bone of the chain to achieve the desired shape.
IK is the abbreviation of inverse kinematic; instead of having to rotate each bone, you have a helper at the end of the chain and moving it will make the whole chain of bones to rotate and follow that point.
FK and IK are the base for rigging, and you will see these two words a lot of times in the coming tutorials.
Each one has its strong a week points and is better for certain type of animation. We will combine both and use whatever suits best for each case (Fig.14 and Fig.15).
A man waving his arm is the perfect use of FK. A walk is the perfect example for IK. One foot must stay on the floor as we move the character's hips. With FK this would be quite difficult to keep the foot on the floor while we animate the hips, we will have to rotate each bone to make the foot stay in the floor, and this will happen every time we move the hips. With IK this is done automatically.
But the legs of a character hanging from a helicopter would be much easier to animate in FK than having to animate in IK as it helps when following the movement of the helicopter.
Prototype and Clean Rigs. Test your Rig.
Prototype and Clean Rig
We test several solutions while building a rig. The result of all that testing is a number of unnecessary objects that were created with a certain purpose but now they aren't needed any more.
Once you have finished or you are happy with your rig, creating it from scratch again will help you to understand your rig better and to avoid unnecessary objects.
Often you want to test a new idea for a new part of the rig; it is good practice to do it in a clean file and once this is fully tested, redo it in the main rig file. Fig.16
Test your Rig
Before we hand over our rig to an animator it is always important to test it. Put the rig in situations you wouldn't expect - move, rotate and scale it; if the rig doesn't break it is a good rig.
Quite often, when we check the rig, we realize that we have forgotten to link a part of the rig or something doesn't deform properly on the mesh.
It is quite difficult to remember to check everything, so testing a rig is our only way of being sure is ready for production.
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