Rotation centre for prims

Hiya
Ive got this rotation query.
I have this shape below which I need to rotate by its centre. I added a small circlle pole in centre, where I want the object to rotate.

The item is linked to the pole (which is now root prim) but centre axis of the shape is different from the pole's axis, as produced by the circle tool (which rezzes any number of prims in a circle arrangement)

The shape was made using 3 oval prims in a triangle arrangement (by specifying 3 pieces in circle tool)

Red mark indicates the actual axis at present with the pole as root (yellow mark). If I rotate it now, it will just rotate around the pole and not on it.

So can I change the axis by adding a transparent prim further out and adding to the linkset (with pole still as root). Does this work and is it a common practise?

I know the only way to find out is to try but I thought I would put the query here 1st. Im happy with the shape and dont really want to change it or the amount of prims used to create it (4)

Does this question make any sense? lol

Right idea, wrong solution. Yoy don't need a counterbalance. You need an axle.

Put a small prim where you want the center of revolution to be, and make that prim the root prim. The linkset will rotate around its root, no matter how lopsided it is.

Looking at your illustration, the current root prim is one of the three circle segments, most likely the bottom one. You'll find the linlset is rotating around the center of the uncut shape of that prim.

I have made a center prim (yellow on diagram!) and made it root but when i select/edit to see axis..its off from the pole (red)..and not the pole's axis

Is the pole (root prim) the prim that has the rotation script in it?

I havent put any rotation scripts in yet..im merely going by the pos of the axis and previous similar problems

If you rotate it using the "grab rings" in edit mode, it will rotate about its calculated center rather than the root prim. If you use the up/down arrows in the edit dialog, or a script in the root prim, it will rotate about the root prim's center.

If you are going to have a script do it then its gonna work as Ceera says, even though the rotation when you are in edit mode looks like it's elsewhere.

edit: too slow

Thanks for that everyone...I shall do that now

Well its rotating (require rotation is very slow!)
but were talking about something that is 40-50m wide so hard to tell where its centre of rotation is! lol

Make the axle temporarily visible, so you can see if it wobbles or not?

Should have caught the manual versus scripted bit.

Grabbing the rotation rings rotates around the calculated center of the linkset, while editing roataion values or changing rotation with a script rotates on the root prim's center. It's one of those quirks of the SL building system that drives builders crazy!

Rotation looks good...thanks guys, learned a bit more!

While Im here, can I also ask another question, though it maybe more script related

I want to do a rotating house/level. That obviously has its own problems like rotating objects being sorta phantom etc

Instead of a house/level that rotates VERY slowly which brings the above problem permanently, what if I get a script (possible custom made) that will rotate the house every so many minutes so it remains normal and non-moving inbetween the rotation movements (maybe a script based on a clock routine!!??)

If it rotates say 1 degree every few minutes, while your standing on it for example, surely that would not be enough for you to fall through!!??

Sitting it said house would be no problem as we all know..sitting & rotating go hand in hand lol

But what about standing & walking about?
I prob wouldnt have doors as that would create more problems so would be based on teleport entrance/exit.

Should I post this query on the script forum?

Taz

You wouldn't necessarily fall through, but all the furniture on that level would have to be linked to the rotating part! It would be an intersting concept, but has a LOT of difficulties in implementation.

I know this project has many problems to overcome but would love to give it a go and will probably not come out the other end as envisaged lol

Yes all the furniture will be linked to the rotating root prim.
Ive looked into various configurations like vertical shell only rotating with centre of room/level remaining static.

Also windows only rotating but then you dont get the 360 view of the paradise scenery when sitting (which also applies to the previous config)

The shape is the one I was trying to get and took me a while to get it how i wanted it....a curved 40m+ triangle. It looks pretty good when flying towards it! lol

I might just try a freebie clock script on a large platform to see what happens when standing on it when its turned a degree every few minutes (assuming I can get the clock script to work ok..only need modded version based on the 'minute' part of the script lol)

I posted a clock script in the script library, that actually rotates the hand prims and not just the textures. That should work for you.

I seem to recall seeing at least one rotating dance floor that wasn't just a rotating texture. I think they had to make it physical so you'd 'go along for the ride' like a physical elevator does when it lifts you or lets you go down...

I'll suggest you probably at least want a small disc at the center that remains stationary, as a place to enter and leave the rotating part.
Good luck!

Let me just add...were not talking about anything moving/rotating as fast as a 'dancefloor'
Im talking about something that moves 1 degree maybe every minute or several minutes. The idea is, to show the resident the whole 360 view of the landscape over 24 hours (or 12)
So at 24 hours, thats 1 degree every 4 minutes!
or 1 degree every 2 for 12 hours.
Now surely if the level your standing on is only moving once every 2 or 4 min, then inbetween its going to be physical right?
And would that quick 1 degree movement be quick enough to NOT allow you to fall through the floor?

Im not a scriptor but if the floor level is in a rotation script, surely it wont be phantom if its not actually physically moving inbetween each applied degree movement every 4 min?

Wouldn't you just maybe shuffle for a second when the actual degree movement kicked in? and not be enough for you to fall through?

Obviously sitting is fine..no problem

'Ceera Murakami'..I may already have that script but if not, I will chase it up.
I dont need any textures rotating..just to put the minute hand script into a large horiz level and change the frequency to something alot slower (i.e. minute hand moving 1 degree every 2 or 4 minutes lol) and maybe change the hour hand to do the same (so 2 minute hands really!) as I have 2 levels but maybe in reverse.

So one level (ground floor) would be modded hour hand script rotating (clockwise) 1 degree every 2 or 4 minutes and the 1st floor level doing the same but opposite direction (anticlockwise)

Taz