How to Split Lip Shapes For Natural Motion 👄 ⚙️ Orbicularis oris is NOT a sphincter muscle. (And it’s been a while since anatomists believed it was.) If you didn’t get the memo from decades past, join the Quad Squad and start segmenting your orbicularis oris blendshapes accordingly. This clip shows me with dental numbing that froze the upper (screen) left side of my lips. Being able to see this type of segmented freeze can be helpful for visualizing the quadrant-style breakdown. 📕 Gray’s Anatomy, 43rd Edition: “Orbicularis oris is so named because it was once assumed that the oral fissure was surrounded by a series of complete ellipses of striated muscle that acted together in the manner of a sphincter. In fact, orbicularis oris consists of four substantially independent quadrants (upper, lower, left and right), each containing a larger peripheral part and a smaller marginal part apposed along lines that correspond externally to the lines of junction between the vermilion zone of the lip and the skin. Orbicularis oris is therefore composed of eight segments that are named systematically according to their location.” 📝 NOTE: I’m specifically talking about lip shapes related to orbicularis oris, e.g. lip funneler, lip tightener, lip presser, etc. You may not need ALL of them split into fourths, but leveraging this breakdown style can help you capture more natural and nuaned motion. For more on facial expressions in animation and technology: melindaozel.com #animation #muscle #blendshapes
This is good to know! I was one of those ppl living with oudated perception of Oo 😄
For a core AU22, AU18, etc. a four way split works fine, but for creating mouth/lip tweaker shapes, the lips needs to be split more in order to shape the mouth to match the actor.
Nuanced*