Lolwut said:
I don't remember having seen any ballsucking mod
We don't have a soft-anatomy physics system. The math isn't terribly complicated (allow local deformation; preserve cross-sectional area; include adjustable parameters for inertia and gravity) but the actual implementation would require a lot of fine-tuning. The breast physics system is inapplicable to the scrotum - it's essentially a giant kludge based on linear motion and it has no spatial relation. Hence - you can put lay a girl supine via animtools, but her breasts will not "hang." You can use animtools to bounce a girl straight up-and-down, yet her breasts will squash to the left and right.
In order to build a ball-sucking mod, we'd need to write a soft-anatomy-deformation framework. I'm
not sufficiently interested in this Request to do so. I think that it's more likely you'd see such work done for a "mainstream" mod idea (e.g. deformable breast physics for groping/titwank, or spankable jiggly buttocks) and then reused/adapted for this idea.
In any case, it isn't really necessary. A "ball-licking" mod presents far fewer technical complications than "ball-sucking" and it would (presumably) be
good enough for people who are into that sort of thing. I'm assuming that
two girls is the real interest here, rather than the specifics of gonad-gargling.
One major issue with any "two girls on screen" mod is
eyes. People place a lot of concern on eye focus (even if we're not always aware of it) - in conversation, we seek clues regarding the attentiveness and engagement of our audience. In a sexual context, eyes can tell us about mood, interest, dominance, pleasure and pain. I would argue that this is a fairly important feature in SDT when it's compared with newer and more technically-complex games (e.g.
Illusion). Many of those games are
less interactive than SDT and yet the information provided by the eyes is still insufficient to give the player a complete understanding of the scene. Hence, the developers must use other means (e.g. voice acting) to "fill out" the experience.
An SDT user who is accustomed to the normal level of character "expressiveness" will probably be
disturbed to see a girl running a completely passive animation loop with a fixed thousand-yard stare. You could lampshade this problem by applying a "hypnosis eyes" mod, or simply blindfold the girl, but she's still going to be missing a lot of subtle animation patterns. It would be nice if the people who are
proposing this new feature could do some brainstorming and planning -- rather than waiting for the mod to be finished and then half-assedly compensating for flaws and oversights in the basic design.
Another example: the girl could probably run a simple "tongue waggling" animation (a licking motion which doesn't actually have any physical effect on the scrotum) and "breathing cycle" animation (desynchronized, of course). This could suffice to give the impression of a submissive minor participant in a threesome. But what if the guy moves along his motion tween? Suddenly she's licking air and the scene looks ridiculous!
Getting the second girl to track his motion tween is technically possible but probably NOT worth the additional effort. Instead, this is the kind of thing which should be solved via
scene composition. Make the guy immobile to simplify the technical requirements, and then setup a position, background, scenario (and dialog if you want to get fancy) which justifies it. Maybe he's a fiancé celebrating his last night of freedom in the VIP room of a gentleman's club. Maybe he's a superspy who was captured and is being erotically tortured for information. There are lots of possibilities.
The point is: do some preparatory work. You may be able to get other people interested in your idea; you may be able to clarify (and simplify) the code requirements; you might mention something
which already exists (and then other forum members can send you a link and you can download it). At a minimum, it proves to the modder that you're willing to invest some time in your idea. It's very frustrating for a modder to get halfway through a project and discover that the originator (who
should be providing feedback, helping with beta testing, and championing the idea) has gone AWOL or stopped caring. If you've shown commitment to the idea then modders will be less reluctant to work on it.
(sitting and bending the back for example)
The SDT girl's back cannot bend - the spine is a single rigid segment. It's possible to create a flexible spine, but
very unlikely that anyone would do so - the kinematics would be complex (too many joints!) and then we'd need to update all of the existing clothing files and rig them to the fancy new spine.
You'll need to re-think the scene, because a rigid-backed "sitting" girl would need a 90° head tilt (aka broken neck). Perhaps she could be resting on her back against a triangular pillow?
If you're interested in this idea,
explore it. Don't just wait for someone else to start writing code. For example - try to setup the second-girl position in animtools. Find a posture that makes sense for all three characters (add a custom background, furniture, etc). Then post some screenshots from animtools (and/or position files). You can even use MSPaint to stitch together two of your screenshots so that we get a "preview" of what the scene might look like with all three characters in-place.
I'm still not convinced that the basic premise is feasible - I can't see two heads fitting so closely together without colliding during deep penetration. I suppose it could work if you just make his genitals absurdly large. Meh - post a sketch or a composite screenshot and I'll admit that I was wrong.