Week 12: Rigging

Character 3 Rig

I wanted to initially rig character three as he is the only one with a planned walk cycle, and I wanted to allow time to properly weight paint the legs so they do not deform in unintended ways.

Starting the rigging process of these house models, I immediately checked that all the pivot points for the doors were correct and in functioning order, as well as the translate and rotate limitations.

Transform Constraints
Transform Constraints

The initial sept is placing the ‘skeleton’, which has just two IK legs and a central spine. One of the most important aspects of skeletal placement I have learned during my time at LCC is not to ruin the rotations by placing the joins in a messy, disorganised way, and specifically rotating each joint hierarchically and neatly so they are on a correct axis.

From here, I used a joint hierarchy bind to attach the mesh to the skeleton, which also selected the closest in the hierarchy so that the mesh influence would attach itself to the nearest joint. Since The house will not require very complex and naturalistic skin weighting, this option should suit the job quite well.

The initial binding, as displayed below, had several issues in terms of mesh deformities. Due to the default influence of the mesh, all the vertices are corresponding to several joints at once, which works well for a more humanoid and natural rig but will not work in this instance.

Initial Skin Weighting Issues

There also prove to be many issues with the IK application in the leg, as the knees seem to deform and shrink and the upper leg when manipulated. While the overall effect of the character intends to have an almost ‘rubber hose’ style, there still needs to be no deformities.

IK Handle

Looking into ‘rubber hose’ rigging techniques on youtube to assess whether this is the best course of action going forward, I found that giving the legs that much individual manipulation, it may complicate the animation in a way that is not necessary for this film. However, the tutorial may be very useful later on for a different project.

Another technique I was looking at the exemplify squash and stretch was to make a ‘stretchy’ spine so that the houses could bend and pull in a way that, again, would not massively deform the mesh. I feel this would be useful however, stylistically, I do not think it will essentially work in selling that the characters are stiff like houses.

The most effective way to bind the skin, similar to my skeleton project, the ‘Danse Macabre’ Dance-off, was to use 100% influence of certain mesh to certain joints so that they did not deform upon movement.

As shown, the current mesh, as it stands, warps and deforms massively due to multiple joint influences.

By going through all the different parts of the mesh and giving them 100% Influence over the central joint that will be the main hip control, the mesh was able to successfully follow in a way that makes sense.

FInished Leg IK
Functioning skin weighting

Despite this, there are still several issues regarding its movement. One of the predominant issues that stand out is the leg deformities mentioned earlier.

due to the nature of the character, I would not be able to get the leg and the knee to be exactly in line with the joints, as there would be no space to bend. However, I successfully managed to get t the knee and upper leg to work in a way that minimises drastic deformities.

In order to 0 all the translations on the leg to avoid the rig going ‘crazy’ I created individual hierarchical groups for each joint and froze all of the transformations.

Interestingly, one of the issues I had was the mesh collapsed in on itself after trying to set influence to the main body of mesh, so due to this file corruption, I had to close and re-open my prior saved file.

I found that in order to get individual eye control, I had to make different joints for each individual eye and eyebrow and set them all the 100% to the corresponding joint in order to get them to move independently.

Hat constrain

Since I wish to add secondary animation with the hat, I decided to research different hat constraints that would allow it to move with the main mesh but work independently from it.

In doing the hat, I made it individually controlled but parented it to the highest joint in the ‘spine’ so that it was able to sit in its original position and could move independently from the body. Could then turn on and off the influence or ‘attachment’ in the transform settings.

Character 1 Rig

Going back to character one, I essentially used the same process in order to get it functioning, as both characters 1 and 3 have very similar features and functioning eyes.

The main struggle with this character was getting the weight paints right due to the very short legs, as to was very difficult to avoid massive deformities due to the lack fo space to work with.

After playing around with this tool for a while, I was eventually able to create an effect where the information was much less noticeable upon bending and settled for its appearance of it. This is an issue I expect to reoccur since most of my characters have shorter legs.

Fixed Skin Weighting
Completed Rig

Posed Rig

Next Week’s Goals:

  • Continue Character Rigging

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