Hello, Doc! I’m stumped once again and seeking your advice. I have a character model that I added 3 hair objects to. When I use the bone controls to move the character’s head (and body), the hair does not stick to the head. What is the easiest way to get the hair to stay put? I am not animating this character. Rather, I am posing her and using her in a printed book.
I would rather not make this particular model public, but am delighted to upload it with your permission.
Thanks, Doc. I’m not sure I understand your explanation. When I rotate the model’s head using the bone controls, her hair does not stay put on the head. The hair in my scene is not exploding; it’s just not staying rooted to the head the way I desire. Adding hair colliders to objects placed in a cage around the ponytail doesn’t appear to do anything to keep the hair fused to the head. Am I missing something?
By the way, it’s totally fine to share screengrabs of the model. I just need to avoid sharing of the model itself.
So, Doc, you are not experiencing the hair “departing” from the head when you rotate the head using the large ring controller that is around the neck?
Regarding the hair on the head without dynamics and the ponytail with dynamics, I am new enough to hair in Cinema that I don’t know precisely how to do this. I can try to figure it out, but ideally it would help a lot to see a tutorial.
I watched the Men’s Hairstyles Cineversity tutorial series, but was left with several questions. Hair seems to have A LOT of nuances. I’m open to any advice you have.
Doc, I just looked at the file you sent me. Thanks. I can see that the hair colliders that you set up are allowing the ponytail to fall naturally with dynamics. I’ll look closer at this when I get a moment. I also see in the file that when I rotate the head, the hair does not stay connected to the head. Are you seeing this? Finally, if I end up going with this dynamics approach, how can I keep the bangs from losing their careful styling?
I think I went through all of them now. While rotating, the hair moves inside the head, but the roots are staying. (I have not the play mode on, which I did before.) I switched the Head Geometry off, and looked from below, so I had nothing behind her hair (forehead area), then I rotate the head, and the roots stay.
The Bangs, I’m not certain if I follow here, but just in case: If the style is done, go to Main Menu> Simulate> Hair Edit> Set as Dynamics. Then go the hair object>Attribute Manager> Dynamics> Rigid ON. Is that what you are looking for?
Here is a sketch (really rough) that shows my suggestion to separate the Hair on the Head (no dynamics) and the Pony Tail (dynamics - if needed). Perhaps that safes some processing time, as well is faster in the preview.
Anyway, I have the impression I miss one feature, but I can’t put my finger on it, I have (as mentioned above) to search. It might take a while, it’s 108ºF here and: no I really do not like ACs
Your instructions for keeping the bangs static are exactly what I needed. Thank you, Doc!
I’ll look over your video for making the ponytail dynamic while keeping the head hair static soon. Thanks again!
I’ll also check out Patrick’s series soon.
Now back to the original issue I’m experiencing. If you discover a way to keep the hair from moving inside the head, please let me know. I feel like something like this should be really simple…like adding a tag or simply placing the hair objects in the correct hierarchy, but I haven’t discovered the solution yet…hopefully soon.
I have checked my assumption from post #1, and deleted it, after I can’t find the reason for any problem with it: the collider works with “donuts”.
I explore your model at the moment, and what really stroke me is the size. I tested a Torus with Hair, and then brought the Rosete of your model in. I had to use a scale factor of 80 to have it fit to the Torus.
This will be my next exploration.
I have created a more detailed screen capture, three parts. The first part shows, while the play head stays on the same frame, that the hairs move in the head, to showcase that the roots are stable, part two.
In part three, and that what I care about, how the Hair behaves while the Play head is moving. The roots stay stable on the head-points. The hairs are not moving into the head anymore.
Screen capture. https://www.amazon.com/clouddrive/share/13VxlxeaYOAdutQOGmEtBZFA87adAEwnfbrALMj6CUm
If I find something else, I let you know – of course.
I watched your video. Even though the roots stay intact, the hairstyle is still falling apart. The funny thing is, I don’t even care about the playhead for now. In a perfect world, I would like to have a ponytail that behaves dynamically, but right now I’m simply trying to find a way to get my hairstyle to remain exactly as it is while I rotate the model’s head. But for some reason, the moment I rotate the head, the hairstyle falls apart. I find it extremely frustrating that Cinema 4D does not have a function that allows for “freezing” a hairstyle so it stays in place on the head as the model moves. I would think that any person doing any sort of model posing would require this feature. At some point, I’ll have to find a solution…otherwise, my book project can’t continue.
Regarding the model’s size, she’s just over 4 feet tall, so I’m not clear what you’re referring to regarding her size.
The Play head is the key here, it refreshes things more often. If you don’t care, as you say, I don’t know what else to do. I tried to make clear that the calculations made based on keyframes and perhaps caching are just crucial, and there it works fine, as demonstrated a few times.
After all it is a simulation. I would say that to simulate real Hair to 100% as in reality, would require that each SINGLE hair is calculate root to tip, with all the interaction among all other hairs, in terms of contact, inertia, friction, bounce, and what ever part of dynamic creates that snowball effect that might even bounce back, and the calculation would need to start over. There we talk about 150,000 hairs with perhaps a huge number of sub-calculations, perhaps a few “zillion” single calculations for one frame. Well, we talk about Guides and they stand for 1,000s of Hairs, first simplification, and many more to follow. Simulation in VFX or CG is always a very reduced operation. Etc. Having said that:
To get the Hair more dynamically the “Steps” as well as the “Iterations” needs to go up. The “Surf.radius,” including all the Rest Mix and Stiffness values, really need to be fine-tuned. Speaking of an ideal world, that would be perhaps Artificial Intelligence to do that for us in a few years. For now we need to know the parameters and even then go through a phase of trial and error, to get the sweet spot of all settings. Which requires knowledge, passion and certainly patience. Sometimes also to trick the application: The Gravity is pulling on it, so lower the mass helps to keep things in shape. The Ridged setting was mentioned earlier.
The application has millions of options to combine, and yes, I never made a ponytail with one Hair Object, I would even try to have the Hair doing two complete different things. Being constrained to the Head and flowing freely as a Pony-Tail. I would split that instantly to have more control.
I understand your mood about this, but it needs some time, and forcing it to work without the playhead running might work with simple set ups. You can easily see how much it takes to even cache the solution, it is certainly based on your set up not in realtime anymore, at least on my computer here. That it can be calculated shows the cache, but obviously not in realtime, and that would be my best guess why things move wildly. You might check with the support. I have no other ideas, besides lowering the amount and test things in a reduced environment.
Thanks for all of your help with this, Doc. When you say that it works fine, I’m guess I’m just missing something because, no matter what, when I rotate the model’s head, her hairstyle goes bonkers. I’ll keep working with this and separate the ponytail into another hair object plus reach out to support to see if they can offer any solutions. This is one of those instances when I really need someone to work with me one on one so I can see what they do and ask questions in real time.
It is certainly in the Dynamics.
Option 1
Switch the Hair>Dynamics: off while you pose the character and all is fine. IF the right pose is found, check the dynamic on. The go to Hair>Attribute Manager> Dynamics> Animation and use the relax function, to refresh the dynamic pose. Press the button until it fits to your liking.
Option 2
Instead of the Play head, you can also switch on and off the Dynamic Interactions. Perhaps that works better on your set up. On mine it gives me some grief (in case I forget to switch it off). Give it a try.
Main Menu> Simulations> Hair Options> Dynamic Interactions.
Since that’s quite a mouse milage to get there, perhaps you set a short cut for it, or just drag the symbol into your interface (Command>Customize) https://help.maxon.net/us/#TOOLHAIRDYNAMICS
It will take a lot of power from your system, if not shut of in case you don’t need it.
Doc, a ray of understanding just dawned on me. The reason I was seeing the hair detach was because I was ignoring the playhead…which, as you know, resets the hair to the proper position on the model’s head. In case you’re interested in seeing why I was struggling, I’ve recorded a 1-minute, 25 MB tutorial where you can see the hair detaching (35-second mark), then appearing not to attach even after running the playhead (45-second mark), then re-attaching after running the playhead some more and this time (importantly) waiting longer for the render region to refresh (59-second mark). If you’d like to see the video, I am happy to upload it.
I mentioned the play head many times, you even told me that you don’t care about the play-head.
I recorded a couple of clips that demo’d it, especially for you, what happens without and what with running Play head.
If you progressed to a frame and then moved the head, sure, nothing unexpected.
Excellent advice in post #12 of this thread, Doc. I know it took me a long time to understand what you were saying, so thanks for sticking with me as I found my way out of the darkness and into the light! Whew!
