3D Art Essentials - Chapter 8 Continued

This is a continuation from the last post, I figured instead of giving you a hell of a lot of information to take in at one time - I figured it'd be better if I split it so it'd be more or for the both of us. Partly because I didn't want to write an insane amount in one go and also to make it bearable for you all. So, let's resume!

Keyframing
Using keyframes is a fundamental tool used in computer animation - with this you define the start, the middle and the ending positions - almost anything can be keyframed: from positions, rotation, size, deformation, colour and the texture. Usually done on a timeline.

Animating with Graphs
Keyframes are placed on a timeline and the animation graphs show a line which is effectively the timeline - this shows all the keyframes and how long each action lasts.

There are three main types of interpolation: stepped interpolation, linear interpolation and curved interpolation.
Stepped Interpolation (key) - the values don't change until the next keyframe.
Linear Interpolation - each keyframe is connected in a line, it's smoother but the animation turns out jerky doing it that way.
Curved Interpolation - the points are connected by a curve, this makes changes in the speed or direction, or any other trait eased in and out of something. It's similar to how a chameleon changes its colour.

These bits were very promising - while I have animated in timeline using keyframes in the past, it's still not a bad thing to refresh your memory of it all. Whereas things like the graph editor that I knew existed but it's just something I have never used before, it's going to be something that I will need to learn and understand by the end of this module if I am ever going to improve in animation.

It also touched on things like Motion Capture - which is where performers in a skin-tight suit with markers on it - act out the movements. It sounds really good and there are a number of games that I know from the top of my head that use this - Uncharted, Tomb Raider use too, even Harry Potter and the Deathly Hallows Part 2 for some who didn't know and so on. This kind of animating is very powerful and looks really cool to use and try out, but for the sake of this project I won't be using it, few reasons for that, main one being that the university doesn't have a motion-capture studio and the most important one of all - it's too expensive. 

The chapter spoke about Facial Animation which is something I will do if I need it, but I figured just in case I will share what I read up on. There was a Facial Action Coding System (FACS) was developed in 1978 by Paul Eckman - who was a psychological studying emotion and facial expressions. It describes 64 distinct facial action units (AUs), it doesn't talk about expressions like raised eyebrows but it goes into detail about what muscles in the face. It's IMPORTANT to understand the universal emotions as they are recognized around the world. There are six universal expressions: happiness, surprise, disgust, fear, sadness, anger.

It's very important to study expressions and get them on point as possible, it's close but not realistic then people will have a hard time to relate to the emotion the character is making. Facial rigs requires a skeleton rig in the jaw - and the deformations in the face require a good underlying topology. Facial rigs can also be a full musculoskeletal simulation - the rig must create several expressions. 

Finally to end the blog post, there were a few things that were worth mentioning - sometimes when it comes to having to animate for dialogue the animators act out the animation themselves while listening to the dialogue track. Draw quick sketches of your animations on paper - make them rough so it's a case of if they are bad they can be easily thrown out. Consider the timing and poses used within your animation and finally, keep a note of the feedback you receive from your animations as it can be very helpful.

That's it for now folks, hope you enjoyed the read, until the next time :)

Biblography

• Chopine, Ami. "Chapter 8: Animation - It's Alive." 3D art essentials the fundamentals of 3D modeling, texturing, and animation. Oxford: Focal Press, 2011. 103-116. Print.