I have always wished I could have a bone share a constraint 50/50 with two different bones.
I found a workaround.
This works best with region binding... actually I only tested it with region binding so there you go.
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Create two bones. Both bones should be identical in every way, same position, same strength etc. These two bones are sort of working as one bone.
Make sure the vectors or points you want to control are covered by these bones. Since they are identical they can go almost anywhere a single bone would go. Just keep in mind that together they have "double the strength".
Now, you can put a constraint on each bone to another bone set to full strength. Since they both have equal control over the vectors the strength of the constraint is shared 50/50 between them.
In my case I wanted a set of teeth to share vertical translation between opposite side lip control bones. I put my double bones over the teeth and constrained one bone to each side control bone.
Now if I move the left side control bone up or down, the teeth move 50% of that bone's distance. If I move the right side control bone the teeth move 50% of that distance.
Works exactly like having two constraints on one bone. I think this could be expanded to as many bones as you want. You could have 4 with 25% constraints to 4 different bones. I plan to play around with this some more and see what else can be done with it.
EDIT:
Doesn't work using rotation constraints. The vectors "shrink" from being pulled in different directions simultaneously. Dagnabbit. At leas translation and scale work well.
-vern
"50 percent bone constraint" for two control bones
Moderators: Víctor Paredes, Belgarath, slowtiger
Here is a sample of what I was able to do with this technique.
Animation:
http://www.lowrestv.com/moho_stuff/compound_bones.mov
Moho File:
http://www.lowrestv.com/moho_stuff/compound_bones.moho
By translating only two control bones I was able to control the ease in and out of the bouncing ball. I didn't have to use any extra key frames. Just the up and down point of each bone. The ease is controlled by the shared strength of each bone. I did of course, change the timing of the key frames but there are only two key frames on the bounce for each bone.
By offsetting the moment each bone hits it's mark in the time line I was able to create this effect. You can move the key frames around to adjust ease very simply.
This isn't perfect by any means, but I think it might have some potential.
-vern
Animation:
http://www.lowrestv.com/moho_stuff/compound_bones.mov
Moho File:
http://www.lowrestv.com/moho_stuff/compound_bones.moho
By translating only two control bones I was able to control the ease in and out of the bouncing ball. I didn't have to use any extra key frames. Just the up and down point of each bone. The ease is controlled by the shared strength of each bone. I did of course, change the timing of the key frames but there are only two key frames on the bounce for each bone.
By offsetting the moment each bone hits it's mark in the time line I was able to create this effect. You can move the key frames around to adjust ease very simply.
This isn't perfect by any means, but I think it might have some potential.
-vern
Did you see this post?
You can see that it can be combined with manual binding.
That's the way I did the eyelid movement in the animation of the dog in this other post.
Great thing the flexible binding!!
EDITED:
Hey!! I think this tip is great!!!!!! I knew the use of two bones to 50% control a point, But your application is fine!!
EDITED-2:
In this case there is no need to use controlled bones... Mmmm I think that you LOVE puppets.
You can see that it can be combined with manual binding.
That's the way I did the eyelid movement in the animation of the dog in this other post.
Great thing the flexible binding!!
EDITED:
Hey!! I think this tip is great!!!!!! I knew the use of two bones to 50% control a point, But your application is fine!!
EDITED-2:
In this case there is no need to use controlled bones... Mmmm I think that you LOVE puppets.
You are absolutely right. There really is no need to use "controlled" bones. I could just as well key framed the two bones controlling the vectors directly.
I use control bones for ease of manipulation and being able to find the bones to move easier in a mess of bones. Sometimes there are a ton of bones in the middle of that specific spot. Selecting a bone in that mess can be difficult. Also I may have a chain or group of bones all controlled by one bone.
My control bones can be away from all the confusion of splines and vectors and other bones. I can put them in a spot where they are accessible and as big as needed for easy selection even when zoomed way out... ESPECIALLY when zoomed way out. Try grabbing a teeny tiny bone when zoomed out.
I also will "stack" or organize the control bones on frame 0 so I know which one does what. Sometimes I attach text image labels that travel with the bone on a non rendering layer. I can always see what bone does what. I just started doing this recently by "accident".
I had labeled one of my "tutorial" projects with text layers that were bound to the bone. This was so cool I started doing it "on purpose" with my own projects.
I am thinking now I could use a simple layer with color filled shapes bound to bones that are the shape of a bone that "colorize" the bones. then I can use colors for indicators.
What I find interesting about the "50/50" control is the ability to create interesting "ease" effects. With just the use of bones and NOT key frame interpolation, you can create some interesting, subtle "sliding" motions not possible with just a few key frames. And these motions are very smooth.
-vern
I use control bones for ease of manipulation and being able to find the bones to move easier in a mess of bones. Sometimes there are a ton of bones in the middle of that specific spot. Selecting a bone in that mess can be difficult. Also I may have a chain or group of bones all controlled by one bone.
My control bones can be away from all the confusion of splines and vectors and other bones. I can put them in a spot where they are accessible and as big as needed for easy selection even when zoomed way out... ESPECIALLY when zoomed way out. Try grabbing a teeny tiny bone when zoomed out.
I also will "stack" or organize the control bones on frame 0 so I know which one does what. Sometimes I attach text image labels that travel with the bone on a non rendering layer. I can always see what bone does what. I just started doing this recently by "accident".
I had labeled one of my "tutorial" projects with text layers that were bound to the bone. This was so cool I started doing it "on purpose" with my own projects.
I am thinking now I could use a simple layer with color filled shapes bound to bones that are the shape of a bone that "colorize" the bones. then I can use colors for indicators.
What I find interesting about the "50/50" control is the ability to create interesting "ease" effects. With just the use of bones and NOT key frame interpolation, you can create some interesting, subtle "sliding" motions not possible with just a few key frames. And these motions are very smooth.
-vern
I disagree with you in this point. The "ease" effect that you achieve is not due to the 50/50 bone compund. It is due to all the keyframes are smooth. Try to change the keyframes to linear and see that the "ease" effect dissapear. In fact you can achieve same movement only with point movements and no bones.What I find interesting about the "50/50" control is the ability to create interesting "ease" effects. With just the use of bones and NOT key frame interpolation, you can create some interesting, subtle "sliding" motions not possible with just a few key frames. And these motions are very smooth.
See my modification of your file. At the bottom there is a new vector layer that copies your movement with points movements only.
http://amanoalzada.iespana.es/Mohostuff ... oints.anme
Only 3 keyframes more than you and every thing in one layer.
Hmm...
I don't think it has to do ONLY with smooth interpolation. Although without setting to smooth it doesn't work, that is obvious. Linear is going to give you the same results regardless. If you move something to point A and then to point B, linear is going to do a start/stop top of motion no matter what you do.
Look at this file and see if there isn't something a little different going on.
http://www.lowrestv.com/moho_stuff/compound_bones2.mov
http://www.lowrestv.com/moho_stuff/compound_bones2.moho
Keep in mind I am trying to avoid point motion. I like bones. You can see from this that key frames in the exact spot for the motion create different accelerations. I have highlighted the "compound bones" to show how they move.
Both bones have two keys, start and finish. The bones stop moving at the same spot in space, but the keys are in different locations in time, creating an acceleration or deceleration that is "different" from just using smooth interpolation. The first bone hits the mark at frame 6. The second doesn't get there till frame 24. I admit that the interpolation has an effect, but there is more than JUST the interpolation going on here.
-vern
I don't think it has to do ONLY with smooth interpolation. Although without setting to smooth it doesn't work, that is obvious. Linear is going to give you the same results regardless. If you move something to point A and then to point B, linear is going to do a start/stop top of motion no matter what you do.
Look at this file and see if there isn't something a little different going on.
http://www.lowrestv.com/moho_stuff/compound_bones2.mov
http://www.lowrestv.com/moho_stuff/compound_bones2.moho
Keep in mind I am trying to avoid point motion. I like bones. You can see from this that key frames in the exact spot for the motion create different accelerations. I have highlighted the "compound bones" to show how they move.
Both bones have two keys, start and finish. The bones stop moving at the same spot in space, but the keys are in different locations in time, creating an acceleration or deceleration that is "different" from just using smooth interpolation. The first bone hits the mark at frame 6. The second doesn't get there till frame 24. I admit that the interpolation has an effect, but there is more than JUST the interpolation going on here.
-vern