The developers of Soul Calibur (including Soul Calibur IV and the new PSP title Soul Calibur Broken Destiny) have delved into the 3D modelling techniques used in the game, but most interestingly they have explained just how Soul Calibur succeeds to effectively in recreating the motion of breasts during battle.
Here is the most interesting part, a detailed discussion of oppai physics utilising Ivy as an example:
Here is an example of breast movement, or what might be called breast jiggle. This characteristic is peculiar to female characters. In both Soul Calibur IV and Soul Calibur Broken Destiny, everything, including fabrics, is animated by “bones”.
On the PS3, there are two separate bones in each breast, giving a total of four, and it is these which give rise to breast motion, whereas on the PSP for the sake of load reduction things had to be simplified. We managed to obtain satisfactory results with only one “bone” across both breasts.
Swaying breasts may be most enjoyable, but from time to time we are warned that they move a little too much.
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