Animation and breast size non-conformity. A quick Blather

[anjenthedog]

Far as I know, animations are fixed to represent whatever models were used in its(their) creation.

 

What that means is that your player (or a random NPC) will quite often be the wrong size or shape to fulfill that expectation, (and no, body-autoresize does NOT solve the issue. often makes it worse in fact)

 

It *seems* like there ought to be a way to idk...fit them better. And yes I know it's an ignorant pipe dream...but I can still dream.

 

for instance, a simple ~quasi SFW example. Suppose two partners in a scene have different heights, or different neck lengths, or different head sizes. In these cases, even a simple standing kissing scene will often result in a mismatch with both characters "kissing the wind", unless the shorter character is "lifted" (shifted actually) off the ground, and for a moderately "short" woman, that can mean translating her off the ground 5 or 6 inches to make up the difference. But... using the auto-resize often  option ends up with "Big Bertha" kissing "the little man", since it rescales the entire character, which is increasingly evident as the nominal height of the character reduces (since the rescale increases as original size decreases)

 

When player talks to an NPC, if they're taller than the NPC, the N PC will look up to meet their eyes. even adjusting their head angle to match. And when the character is shorter, they look down to meet the players eyes. Seems like there "ought" to be a similar mechanism in play for meshing in animations. (it's pretty obvious that a node-to-node difference that is used to calculate the adjustment angle for the eyes and head position...

 

So what's that have to do with breast size you ask? Same basic thing. Seems like all the animations expect D sized tits, or else no contact.

 

Things get even more complicated if you choose to adjust the skeleton, for instance, to make a petite "cheerleader" type, where body proportions change "drastically" from the expected, stacked, large hipped, 5'9"-6' tall Nord female

Edited April 14, 2025 by anjenthedog

[traison]

So basically FootIK but for tits is what we're thinking here? One issue though, when you morph nodes with NiOverride you're not actually moving the node itself in any way. Physics engines and animations move nodes, morphs move vertices. Thus the inverse kinetics implementation would have to not only find the node position, but also the closest vertices between 2 nodes. It would also require hints to be added to SL animation files that can say things like:

 

facepalm.json: "At frame 1234 of facepalm.hkx, start lerping NPC L Hand of actor A towards NPC Head of actor A using IK."

 

Perhaps in the meantime you could do something with one of the screenshot poser mods. Fairly certain I've seen one that allows you to rotate/move bones. Screenarchers use these to fix limb positions, even during animations.

[anjenthedog]

Yeah I realize the amount of  (potential) grind involved... It's just a petty rant honestly. And then I start to think about how it could be done, (maybe a combo of a batch animation sequence preprocess step - like Bodyslide or FNIS, rather than in-game -  AND some "realtime" scripted adjustments in game), but no matter how I approach it, it ends up escalating to a clock hungry beast with all the realtime calculations that'd be needed for all the various elements, to the point where it'd be more suited to a 4THz computer than a 4GHz one...

 

 

[traison]

Inverse kinetics is not that bad. Foot IK is pretty much a raytrace downwards from each foot node. If it hits, the foot snaps to the ground from where the animation told it to be. Practically every competent game has at least foot IK, including Skyrim. If you want an example of it done right in a larger scale, look up GTA 4's ragdoll physics. Not sure any game has done IK like they did since then.

[anjenthedog]

Ok, so they do use the principle then. Which means it could be used elsewhere.

 

like...how do they pull off NPC eye tracking with Player? Because when in-dialog, most definitely their eyes move AND their heads rotate - up down and left right - to accomplish the "immersive" interaction (aside from any interposed "facial expression"). They have to be doing some calculation (~realtime) of expected position to make it work.

 

 

[traison]

Dialogue eye movement is tracking a specific node of the other actor. There was a funny mod someone made long ago named something like "hey eyes up here", which moved the target node between the tits on female characters. It broke some other things I recall so it probably never took off. Anyhow, I wouldn't use rays for eye tracking as it would be cheaper to calculate the angle between 2 points, and morph the eye vertices accordingly. Rotate the head node to avoid eyeballs doing 360's.