Simulation Tech Talk
SimGuruMax
Posts: 105 SimGuru (retired)
Hi everyone!
My name is Max Rebuschatis and I am one of the engineers of our love letter to y'all - The Sims 4 Simulation.
Animation, design, modeling, and engineering all collaborated to create a fresh, exciting, and detailed take on our beloved virtual people.
There is surprising complexity in this system, and it is my pleasure to discuss various facets of the tech.
I'll start with a couple examples:
Did you know that Sims do, in fact, have an innate handedness? We determine the handedness of a Sim based on their unique id and roughly 75% of Sims are right-handed! This affects their default pickup hand and various other animations where mirroring is available.
Ever wonder why Sims will walk some distance to eat near other Sims? We have a sophisticated scoring system that bakes a large number of preferences into meters, which then allows us to compare routing to different objects directly while including things like object types and relationships.
Feel free to ask me anything you want about the simulation tech in this thread. I'll do my best to answer as much as I can within reason.
-Max
Note: this discussion was originally in Technical Discussion, but this seems like a more appropriate place for it. You can see the original discussion here: http://forums.thesims.com/en_US/discussion/782786/simulation-tech-talk-i#latest
My name is Max Rebuschatis and I am one of the engineers of our love letter to y'all - The Sims 4 Simulation.
Animation, design, modeling, and engineering all collaborated to create a fresh, exciting, and detailed take on our beloved virtual people.
There is surprising complexity in this system, and it is my pleasure to discuss various facets of the tech.
I'll start with a couple examples:
Did you know that Sims do, in fact, have an innate handedness? We determine the handedness of a Sim based on their unique id and roughly 75% of Sims are right-handed! This affects their default pickup hand and various other animations where mirroring is available.
Ever wonder why Sims will walk some distance to eat near other Sims? We have a sophisticated scoring system that bakes a large number of preferences into meters, which then allows us to compare routing to different objects directly while including things like object types and relationships.
Feel free to ask me anything you want about the simulation tech in this thread. I'll do my best to answer as much as I can within reason.
-Max
Note: this discussion was originally in Technical Discussion, but this seems like a more appropriate place for it. You can see the original discussion here: http://forums.thesims.com/en_US/discussion/782786/simulation-tech-talk-i#latest
Post edited by SimGuruMax on
48
Comments
I think it's more important to note that 25% of Sims are left-handed.
The infinite pie anecdote is hilarious (and I feel bad for saying that
ETA: clarity
I'm not a psychopath. I'm a high-functioning psychopath. Reaper
I'll compare to TS2 as an example.
In TS2 sims were a lot more involved with minor items like plates, mugs, books, items on the floor etc I mean they looked as though they physically touched them whereas with the latest iterations in the series, these bend down, pick up animations have turned into a swish of the hand it's there or a slight-extended-hand curtsy it's there.
I hope I've explained myself well :-/
I am less interested in discussing bugs, however I will entertain all questions that I feel equipped to answer properly. I would say when in doubt, go ahead and ask. I can answer questions about multitasking, autonomy, animation, postures, performance, etc.
I completely understand your question. Yes, we did have what we call "registration" with objects in TS2. We decided against this in TS3 and TS4 for two main reasons: First, it creates harsh constraints on where Sims can stand to pick up / put down objects. There is only ONE slot you can go to to pick something up. This means that Sims will fail to handle carryables MUCH more frequently and it causes house and object layout problems. The second reason is related to the first, which is that it causes a content explosion. Take drinks, for example. Did you notice that there are several different types of glasses? We have tumblers, coffee mugs, martini glasses, etc. Each of these requires a different grip. Since each requires a different grip, they require unique pick up / put down animations. If we want to have say three different places you could stand to get perfect registration to pick up an object, that means we need to author three versions for each grip times 2 for up/down. This multiplies out very fast.
Instead, we went with a loose constraint and a generic swipe (we still need different versions of the swipe for different grips). This lets Sims move through the house more fluidly and interact with carryable objects more reliably and flexibly.
In general, we tried to go for flexibility and smoothness over exact perfection in many cases like this. This is also why we have more clipping while routing - we decided trading the foot tapping from TS3 was worth it.
Does that make sense?
I worked on MySims, MySims: Kingdom, The Sims 3 (base game), and have been on The Sims 4 since practically the beginning.
I am not 100% certain I can share this, so I will leave this as an exercise to the reader. Our environment and modeling team did a great job, though, I agree!
Excellent. Thanks for explaining that.
I'm not a psychopath. I'm a high-functioning psychopath. Reaper
Will the Mendelian genetics that was in TS2 be making a return? It was so wonderful to have realistic genetics with dominant are recessive genes!
Also, for family trees will we be able to add other extended family households to our relationships? It would be amazing if we could add in-laws, and grandparents, and aunts, uncles, etc to our family tree without having to be limited to the eight sims we can create per individual household in CAS.
Yes, it goes on and on, my friends
Some people started playing it not knowing what it was
And they′ll continue playing it forever just because ...
Thank you so much for taking the time to answer our questions and I hope that mine aren’t too silly.
Happy to answer questions, unfortunately these are beyond my purview. You should bring this up with SimGuruGrant or SimGuruSemedi. Sorry!
Hi Max. There is an issue with the first kiss interaction and the kiss on the sofa and other sitting places were sims lips don't touch. It makes it hard to take a picture for a story. Can that be patched or is it too late to fix animations after the game is out?
This is an interesting issue with registration. I will make sure that this has the attention of our animation team (though they already probably know about it) - having strong animations is one of our core principles and we take our animation quality very seriously in The Sims 4. I can't make any promises but it is never too late to touch up this kind of thing.
Thank you.
Great question! This gets back to the idea of a graph of your entire house that I was talking about earlier.
The first question is where is your Sim going? Let's say you are heading to sit down on a chair in another room. We have the node in the graph for the chair and know the position your Sim will have to stand in order to animate into the chair. We also know that there are two ways to get out of the bathtub. So now we have your source and destination - we know you will start at either of these two locations near the tub (after playing one of two possible animations in the future) and we know where you want to end up. After that, we just do a path plan from the multiple source locations to the destination location and our awesome path planner figures out the best route to take. The result includes which of the sources was selected and we just play the associated animation so your Sim gets out on that side.
This also extends to more complex paths where there are multiple start and multiple end points - like the option of sitting down in one of many chairs to watch TV, for example.
O__O Wow. That's so cool! A lot of effort went into the overall routing and AI I see! I have another question though. Let's say my sim Mom makes breakfast in the morning for the whole family. And everyone else is really hungry. I realized that the sims will still get food even when the mom is serving up a whole dish. Is the sims autonomy based on needs, emotions, and surroundings? Or is it a mixture of the three?
Possible - absolutely. We have a suite of animations in CAS designed to make the Sims playful and fun to experiment with and this suite could be expanded if that is what we decide to spend our time on. No promises on that last part of course, but I encourage you to suggest this to SimGuruGrant.
I am not entirely sure I understand your question. I will put this out there though:
Our autonomy system does have awareness of Sims who are actively cooking. Other hungry Sims are *supposed* to wait for that Sim to finish cooking *if* they are making a group meal. You may be running into some issues with that system?
Have you tried the "Call To Meal" interaction yet? We designed that as a hook for our players to be able to more easily get their Sims to eat together, though we also tried very hard to make it happen naturally and autonomously as well.
If you want to clarify your question, I might be able to shed more light on this.
I guess it is a bug then.
EDIT: Didn't read the second post.
Whoops, missed the second part of your question. Autonomy is based on a large number of factors - too long to mention them all but they include
- Motives
- EMOTIONS
- Relationships
- Situations / Events
- Objects (and proximity)
We made it a point to have our Sims be smarter, more autonomous, and more aware of themselves and their surroundings. Emotions is a huge part of it, but we also wanted them to take better care of themselves and allow the player to focus more on the long-term and other exciting aspects of the gameplay.
Hopefully this answers your followup as well. Autonomy is a complex system with many inputs and is an example of a case where the whole is greater than the sum of its parts.