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raw-m
12-24-2013, 12:40 PM
Got a single object made up of lots of pieces. I need the inside pieces to rotate quicker than the outside pieces around a common centre point.

Thought I could do this with Part Move but can't get more than one rotation out of the gradient. Anyone help?

RebelHill
12-24-2013, 12:47 PM
You'll not get more than the one rotation out of the gradient, because the value after the last key isnt continuous (it doesnt keep going up linearly). Personally, Id take a constant rotation, multiplied by time (so it constantly increases) then remap this value based on distance to rotation origin to obtain the rotation for each part.

Sensei
12-24-2013, 01:25 PM
You can make weight map with 1.0 where is one piece, and 0.0 where is other piece.
Then math > vector > multiply by 0.0 (from weight) will cancel that vector input
and multiply by 1.0 will fully utilize that vector.
Add two such together. They're mutually exclusive.
Set up two different rotation speeds for each vector.

raw-m
12-24-2013, 02:02 PM
Thanks all. Throwing in the towel until next week now but thanks for your input.

RH, do you have a screen grab of what you mean? Those Item Positions are referencing nulls rotating at various speeds so don't think I'm far off.

Sensei, thought about weight maps but there's a lot of items in the object and haven't yet found a way to set all connected polys to the same value without a lot of faffing about.

Sensei
12-24-2013, 02:04 PM
Sensei, thought about weight maps but there's a lot of items in the object and haven't yet found a way to set all connected polys to the same value without a lot of faffing about.

Weight Polygon Groups interactive tool does it in a few seconds:

raw-m
12-24-2013, 02:06 PM
Haha, I wondered how long that would take you :D

Sensei
12-25-2013, 12:54 PM
3 rotating pieces with different speed/direction.

118894

jeric_synergy
12-25-2013, 01:34 PM
3 rotating pieces with different speed/direction.

118894
Wow, I don't comprehand that at all. Works beautifully.

Sensei
12-25-2013, 01:45 PM
Change Node Displacement Order to Before Local Displacement. It will allow placing rings in other position..

jeric_synergy
12-25-2013, 04:49 PM
Here's my comprehension problem:

Transform2
Purpose
The Transform2 Vector function provides a method of translating a
vector using a user defined matrix.

Since I have pretty much zero idea of the utility of transformation matrices, this might as well be Swedish to me.

---But, I have had fun inputting various values into the UP parameter. You can get some wild animation. So, not a total loss.

Rebel Hill might consider that inclusion for his Fourth Volume on Nodes. The UTILITY of operations, not so much the theory. I know it's a fine line.

118900

Sensei
12-25-2013, 05:08 PM
If you don't understand "vector multiply by matrix", you won't be able to use it in any serious task..

Transformation of vector is used by rotation, and scaling.
If matrix would be 4x4 it could be used to translate vector and project from 3d coord space to 2d coord space (by perspective camera or OpenGL perspective viewport).
You have to prepare matrix for them.
In rotation it should have normalized normals though.

Matrix can be build by Math > Vector > HPBMatrix. Connect Up to Up in Transform etc. with rest.

jeric_synergy
12-25-2013, 05:38 PM
If you don't understand "vector multiply by matrix", you won't be able to use it in any serious task..

That's a problem then. :cry:

Thanks for the example to tinker with! Merry Xmas! :D

raw-m
12-29-2013, 02:48 AM
Hi Sensei, big thanks for this! I'm struggling to understand what is going on there, but it looks powerful. I need to refresh myself with RHs node tutorials. Is there a way to tell each weight to rotate at a specific speed?

Looks like I may be pulling the trigger on your Promo offer before the end of the year!

raw-m
12-29-2013, 04:49 AM
Well this is brilliant, and no 3rd party plugin! Thanks Sensei.

Although I'm still getting my head around what is going on I've managed to tweak the setup to get each weight to rotate at a specified speed!

PS. plugins bought, waiting for reply :D

Sensei
12-29-2013, 08:49 AM
Is there a way to tell each weight to rotate at a specific speed?

Change weight map sign from f.e. +100% to -100% to reverse direction.
50% weight will be rotating 50% slower than 100%, that's rather obvious.