It is to limited, its not made to have sex were you need body parts to function.

@skidrow Unity 5 and Unreal 4 are the most popular engines right now, there are shit tons of plug-ins and already established pipelines to make all sorts of flexible and dynamic systems.
Unreal Engine 4 is even open source and you can modify to your needs with C++.
I can't imagine that the dev of XStory Player can come up with a better Engine than Unreal Engine 4 on his own and not waste months of work which could have been done in weeks with UE4.

Would be interested in seeing development stuff. I know it takes effort to post, but the community could give input before everything is set in stone and we end up with the fairly undocumented and not always useful scripting and modding systems we got before.

Actually UE4 character animation features would allow for some really interesting game play. Also, it is not as if someone could not make a whole new class of character model in game. Every game has specific features that an engine does not provide. That is why there is a lot of middleware and custom object development. With something like UE4 you would not be messing with basic things that make the gamer operate and free up time developing features of your specific game. That is why generic engines exist. It reduces the barrier to entry.

As to what UE4 could contribute specifically there a TON of animation tools. Including physics integration with an animation sequence that is adjustable. So you could have a fixed pose that allows you to move the legs and arms around to some degree (configurable). They also have dynamic IK adjustments in the animation itself. So if a character is standing on steps one foot might be lower than another. So the IK will cause one foot to lower down, while the other is raised up. So animation poses are not fixed.

I was thinking these features could be combined to allow the pose to be fixed (by the animator), but create dynamic IK targets for the hands, knees, feet, butt, etc. Then allow the model to be moved in an existing pose and have a target become disconnected when say a foot is lifted and moved then it would search for another target to place itself. That would allow you to take a sitting pose and spread her legs for example. There are a ton of blending animation capabilities so that those new poses could be animations themselves that are blended in as well. So perhaps the dynamic IK is not even needed. I am continually learning that engine and I am so amazed at what it can do.

Using an available Engine like Unity or UE4 its hardly possible to implement stuff like cloth dragging, a feature i really like in XSP. ^^
*EDIT*: Had to change my mind after i saw this tech demo: https://www.youtube.com/watch?v=sbrFIp73tbw

I think it is a good idea to have a dedicated engine for XSP.

I wonder if v4 will have several features i really do miss in v3 like:
(1) scriptable objects
i could imagine building complex objects from building blocks makes modding fun again. ^^

e.g. something complex like the chains could look like that:


(2) instinct driven AI using something like deepmind and teachable posing
i have allready mentioned this here:
viewtopic.php?f=6&t=4003

Yeah. A better connection to the models through a better ai would be amazing. I d love a sandbox dungeon where you could comeback and the slave ai would remember past sessions. Would allow for some fun long term training

LOL, "hardly possible"...

Here is a question in the forum:
https://forums.unrealengine.com/showthr ... make-cloth

Literally its a plugin to do it using Apex from Nvidia. The only difference after that is deciding what can interact with the cloth.

Being able to model cloth is a far cry from modelling clothing worn by another model. I've never seen another engine do anything close to what this one does.

And quite beyond that, there's the body cavity physics (to put it politely). I don't think UE4 has anything in place to facilitate dynamically detecting a penetrating object and animating the vagina/anus/mouth to fit it. There's definitely room for improvement in XStory's engine here, but that's in absolute terms, not comparative, since there's no other engine that does anything like it. Everything else uses canned animations, and few even look better than the completely dynamic animations XStory has (Girlvania is one example that looks better, but is completely pre-animated).

The simple fact is, none of the commercial 3D engines are designed to accommodate a game where you rip clothing off a woman and have sex with her in completely arbitrary positions for both models.

Far from accelerating development, I think adopting a commercial engine would just set up a bunch of brick walls standing in the way of crucial functionality. At least at this time.

I allready edited the post even before you answered...
As i said I had to change my mind because of the nvidia flex tech demo. There are allready flex rigs out there now and with flex clothing it might be possible to recreate xsps engine features with ue4. I am downloading ue4 atm and will do a prove of concept on this topic. Lets see whats possible with that new sys. ^^

The previous post based on deprected knowledge. I tried to recreate xsp features with the old unity engine which was extremly slow because of the poly select and drag algorithm i had to write. Finding the correct polygon in a mesh takes log(n) and dragging it requires to alter every polygon next to it which takes n*log(n) runtime again. This results in n*log(n)² runtime which is nearby a worst case for 3d stuff... only n² could be worse

I think you are just making the problem harder than it has to be. Clothing can be as simple as weighted nodes in a mesh. They have constraints against each other. I cannot remember the term, but there was a specific term describing those nodes. The tricky part will be is it colliding and is there a "rest" condition. Otherwise the calcs could be nasty.

What I did not understand about your post was "not possible' in an engine that provides full C++ access. The UE4 engine is a blank slate with a lot of background stuff done for you. So adding a new physics object like clothing has to be easier than writing an entire engine from scratch. Yes there are paradigms built into the code, but I have worked with game engines that have both simple physics and complex physics all working together in the same space. It just depends upon the interaction you want. Nobody gets a game engine thinking it does everything they could want. That is like saying minecraft clone is not possible because it doesn't write the specific terrain code for you already.