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Algae998
01-21-2014, 06:43 PM
Hey all,

So, its been a while since Ive fully rigged a detailed character, and this one is giving me a lot of struggle. Most characters Ive rigged were with a simple rig and cartoony tube arms that made deformations easy.
I cant seem to get better deformations, no matter where I place the bone or how I adjust the weight map. I know muscular characters are more difficult to rig due to the geometry and definition.
Given the high poly count for this model, I have been selecting chunks of polys to create the weight maps then using the FI's weight map blur with varying settings. There are also similar issues with the hips.
I dont have a lot of knowledge/experience with rigs like this, basic bones and simple IK is about the extent of my rigging abilities, so any tips would be greatly appreciated.

Any tips on how I can fix this?



119489

OFF
01-21-2014, 07:45 PM
Hey. I am also interested in similarity issues and even started a separate thread to discuss it:
http://forums.newtek.com/showthread.php?139026-Character-setup-lab-Shoulder-test-room

RebelHill
01-21-2014, 07:56 PM
First off, your model is too dense, you'll never get that kind of mesh density to work well. Second, weights won't really help you either, neither will blurring them on account of how LWs weights work. See here... http://www.youtube.com/playlist?list=PLTds3QePYrWEWipwKkLmyNT4Tf_JTigM2 (especially vid 9) for various details, explanations, etc.

lertola2
01-21-2014, 08:00 PM
I feel your pain. I have to pose dense models like this fairly often and I always face the same kind of problems. The shoulder is the hardest to get right in my experience and I have not found the ultimate solution. I am usually working on still images so that makes it easier. Animation is a more dificult problem. Here are things that I do to try to fix deformation problems.

1. Render the figure from a view that hides the problem.
2. Save transformed and fix the problems in modeler.
3. Play around with weight maps to try to fix the problem. I hate this process. Its hard to know what a change to the weight map will do. You can spend hours experimenting without ever getting it to look good. I try to avoid using weight maps as much as I can.
4. Make corrective morphs. This can be very tedious and difficult because you have to create a morph in the unposed state that will result in the correct shape in the posed state. It is a very hit or miss process. Mostly miss.
5. Delete all the polygons in the problem areas and re build a low rez version so that subpatching the object will take care of the problem.
6. If you are animating make a low rez version of your figure. The deformation is just better if the figure is low rez. You can make a displacement map to add the body detail after bones are applied to it. Zbrush is very helpful for creating a displacement map that can add detail to your low rez figures.
7. I haven't done a job with this yet but I just got I just got 3rdpowers cage deformer plugin (http://www.3rdpowers.com/index_store.html) which I am hoping will help with these kinds of problems.
8. Render it with bad deformations and then fix the image in Photoshop.
9. Add little bones in the problem area that you can use pull the mesh into the shape you want.

erikals
01-21-2014, 08:04 PM
First off, your model is too dense, you'll never get that kind of mesh density to work well. Second, weights won't really help you either, neither will blurring them on account of how LWs weights work. See here... http://www.youtube.com/playlist?list=PLTds3QePYrWEWipwKkLmyNT4Tf_JTigM2 (especially vid 9) for various details, explanations, etc.

and video 10...
http://www.youtube.com/watch?v=sPyrD1t-4YY

bobakabob
01-22-2014, 12:50 AM
Yes, best advice is to drastically simplify the mesh, especially round problem areas. Either do it manually or use Zremesher. Try dispensing with weights altogether and use hold bones to prevent unwanted distortion.

hrgiger
01-22-2014, 06:20 AM
Two things I would say about animating the shoulder.

1. As has been mentioned, the mesh is too dense. And beyond that, even though you have a consistent grid of quad polygons, theyre not really laid in a flow that considers how the parts will move or deform. There's plenty of info out there on poly flow and deformation.

2. Know that shoulder movement is not just based on the rotation of the humerus bone, it also the other bones of the shoulder assembly, the clavicle and the scapula. Anytime you raise the arm out at shoulder level and above, the entire assembly is involved. If you do a search, you might be able to find a few videos I have seen that show an xray of the shoulder in motion.

Algae998
02-12-2014, 04:12 PM
Hey guys, sorry for the delay and thank you for the responses and suggestions.
I had to switch gears but Im back to show my workaround. My biggest hesitation to retopologizing the model was losing all the facial morphs I had just finished. Then I found that morphs will still work if parts of the model are deleted. Taking all of your suggestions about the mesh being too dense, I deleted and retopoed the body, keeping the original head and morphs. After a bit of object/bone parenting, I got the head and body working properly as one, with much better shoulder and hip deformations. Displacement and normal maps fill in the rest of the details. Ive attached a screenshot of the new lower res body and head.
Thanks!