Render Tests
After my initial render test, I found that it appeared flat and the lighting did not showcase any of the modelled backgrounds, without any clear accentuation of the character and the skull. In the initial storyboard, I have drawn a dramatic spotlight that falls onto the skull. Trying to translate this into 3D, I was able to create a much more effective and cleaner shot by researching and testing Arnold’s renderer sampling.
Below showcases the final render I was able to produce as a test for this shot, as due to the new and improved 3-point lighting set-up, I was able to accentuate the background with a soft focus. By raising the sampling of the specular and sss settings, I was able to drastically reduce the noise and create a cleaner, more in-focus close-up shot. While there isn’t a dramatic spotlight which focuses just on the skull, I liked the idea of using the same spotlight that is present in the wide shots, so that the cut between the two did not appear so drastic.
Rigging
In previous weeks, I had begun to place the joints within the skeleton rig, however, after attending a workshop which explained the process of joint placement in a cleaner and more professional manner, I decided to start the process from scratch. This included first of all addressing issues of my model, to make the skin binding process less problematic later on.
Model Cleanup
The first issue I encountered was separating the fingers from the hand mesh so that they could rotate independently which, due to the nature of the model, works with a ‘floaty’ and disconnected aesthetic due to the obvious lack of muscle.
The secondary aspect I needed to fix was the mesh grouping and overall mesh hierarchies so that they move and function together as they would within a real human body. Due to the numerous issues that I faced and encountered during the collaborative module with the seagull models and rigs, I was able to learn and adapt from these mistakes (such as incorrect transformations) with a better understanding of rigging preparation.
Freeze Transformation Issue
When setting the freeze transformations on all the different sections of the mesh, I had some issues in which some of the parts of the toes would enlarge considerably and realised it was related to the mesh group’s history.
In order to fix these issues, I removed all the relevant mesh from the group and deleted the group in the outliner. Then I selected each individual piece of mesh and deleted its history and froze the transformations. When regrouped this removed the issue, and functioned correctly.
Before beginning the rigging process, I ensure that all of the mesh worked hierarchically and, and was connected and cleaned correctly so there would be minimal issues later down the line. This is uniquely important to my project especially, as I have plans to use the unrigged model to potentially animate the different limbs falling down a hole. In order for this to happen in a sensical way, I feel as though the main attaching joints that will work hierarchically in the rig should also work hierarchically in the mesh groups.
Joint Placement
Starting the joint placement process of my character rig, I started with the spinal area, which is the central point of the joint hierarchy in the pelvic area. From here I manipulated from the front and side viewports, the rough exact placement of each point, but only by rotating the different joints hierarchically to avoid messy translations.
By placing locators at the various joint placement areas, there is a clearer idea and indication of where the joints should be created and rotated, so I completed this process on both the arms and the legs and began to place the joints in a similar fashion as to that above.
A Key point we learned in class was to create clusters so that the central point of the mesh could be snapped to, enabling more accurate joint placement within the inner folds of the joints within the fingers and toes. This was an extremely useful tool that I will always consider during the rigging process going forward.
Technical Issues and Solutions
one of the key elements that I had already pre-planned contingency time to figure out was the creation of a detachable rig. Initially, I had issues with considering how I was going to go about it. My first idea was to create a separated rigged leg and attach it to the same group as the rest of the body. However, in doing so, all that happens is the joints join the rest of the rigged hierarchy. Since this was not the intended outcome, I explored the use of different parent constraints that would allow the joints to follow the main hierarchal joint without being inherently attached to it. This way I could skin weight the mesh to the joint, and have it detach from the model with the same control.
I also repeated this parenting process with the upper arms, so that they could be detached in a similar fashion, and once all the joints were functioning correctly hierarchically, I was able to start thinking about IK handles.
IK Controls
A Key issue I found early on in the process of creating the Leg IKs is that it limited how detachable I could make the rig, as the lower legs would not have the same individual control as previously. However, The leg itself where it was joined at the hip could still be detached, and I viewed that as successful due to the fact it would not be highly necessary for a vast majority of the film.
when creating the foot rig, we learned in a class workshop that by layering different groups together and designing with different functions, you could create options such as toe taps and foot rolls. Applying this to my rig will prove useful long term, as a lot of my planned dances for the characters derive heavy influence from ballet, which required the toes to be expendable for animating purposes.
Issues and Solutions with Legs
One of the initial issues I encountered with the IKs in the leg was the exploration of using two joints instead of one, in an attempt to make them detachable. My initial theory was that, if I created two joints at the knee, I could skin weight the surrounding mesh of the femur and Tibia (and Consequenctly the fibia) to have 100% influence on each. while they functioned in FK mode, Within IK it caused several issues with the knee, as the use of several joints caused an unnatural and strange bend that would not have worked. Fixing this, I decided to focus on the upper leg is detachable, while the rest of the leg functioned like a normal IK System.
Tutorial: Rigging an IK Arm in Maya – YouTube
In a similar light, I began to have the same issues with the arm Iks. The initial problem I seemed to be having was that the arm IK would not bend when manipulated. My initial thoughts were that perhaps I had used a single-chain resolver. However, This did not appear to be the case. Looking at the tutorial linked above, I found that with the addition of an extra joint in the forearm, I was able to connect an IK handle to the joints from the upper arm to the new joint and it would bend in the correct way. However, It is imperative to change the centre point of the Ik handle to the wrist joint, so it is easily manipulatable.
The Iks within the arm though however, did not allow me to be able to detach the joints effectively, and even with an IK/FK switch I realised that the task would be time-consuming and was not necessarily needed, as the arms do not make contact with the ground or objects that really require IKs. In this respect, I made a list of videos that will be useful for this pursuit when I find it necessary to learn and try.
Skin Weighting
Initial issues in which normal skin binging options did not effectively apply to my skeleton character, as the influence needed to be directly affecting each joint 100% in order to act and move effectively like real bones rather than skin. In order to do this, I selected each joint and added a weight flood to the areas (especially the detachable ones) in order to get the correct impression of movement.
Since I had initial issues in which the ribs were moving independently from the spine, I attached the influence to the part of the spine that connects with the clavicle and arms so that they can twist and move as a unit when it comes to placing constrain controllers.
Below highlights the skin weighting and how it functions with twists in the spine, as it was the only part of the mesh I did not apply 100% influence, to allow space for mesh twisting and bending.
The skin weighting methods proved effective, particularly when creating detachable arms and legs, and I was eventually happy with the outcome and the result of my trial and error.
Constrains/ Controllers
The last step I had to cover was creating the join controllers, as I had to ensure that they were attached correctly in order to manipulate the detachable elements without disturbing the skin weight painting.
When adding controllers, I feel an important step as a rigger Is to consider the transform and rotation limitations so that animators do not break the rig. In this respect, I added several limitations to the hip controller primarily so that the legs would not start reacting incorrectly regarding volume.
In spite of the issues I had with the leg control, I found I eventually had to opposite problem with the arms, as the extra join that separated the upper arm (humerus) and the lower arm (Radius and Ulna) was required for correct skin weighting in order to make them detachable. This part was essential for my shot animation, so after the addition of this, I committed to FK animation in the upper body.
In the end, I was able to create a fully functioning rig that was capable of detaching itself the best I could manage to get it within the time contains. While it is not perfect and could be explored much further in terms of IK/FK switches and More extensive facial controls, I feel the rig will suit just fine for the animation and animation style I intend to create going forward. Next week I will finally begin the animation process and will create some animation tests to push the rigs limitations.