Freeze Transforms


#1

Hi guys,
Is there any way to freeze transforms in rhino? Every 3d app has it really, be it polys or nurbs.
Anyway, i will explain why i need it, and if there is any workaround.
Imagine i do a simple circle, in top view. Everything is default CPs.
Now i will rotate the circle say 30 degrees, when viewing it from front view.

Now… If i try to use the REMAPtoCP command, that is, it will remap, but it will apply too the rotation transform (the same when i rotated the circle). One can clearly see, what is going on. If there was a way to freeze that rotation transform, it would have remapped fine.

So, how can i remap it but by using the objects local axis. It seems it is remapping it by using world coordinates axis.
Thanks.


#2

By Default, Remap remaps from one view’s active CPlane to another view’s active CPlane. So to get what you want, you will have to set a CPlane to the object (preferably in the Perspective view) and then Remap from that viewport to another. You can also type the CPlanes directly at the command line…

HTH, --Mitch


#3

Hi there… thanks for answering.
Your workaround doesnt really work. I just tried. It will work only in 1 view, not in all 3d space.
The reason for it, is that if u change your default CP to the objects CP, then the right view and the others, will not be the default right views, will be different, so the object will only appear right in one view, and in the others slanted.

Whatt i really wanted to know basically is… After you apply a transform to a cube, say, a rotation, its local axxis will be aligned logically to that rotation and not world space coordinates, which makes sense. I wanted now to reset those trasforms on the cube, so that, even though the cube is rotated, it s local axes will be the same as world space. Basically this is the issue, and that why it s very important to freeeze transforms. This applies to any software. It 's just maths.
Is there a way to know or get info about the local axis or coordinates of an object? There shoukd be.
Thanks once again, for your prompt answer:)


#4

The answer is quite simple. Objects in Rhino (except for blocks) do not have a “center”, a “local axis” or any form of historical knowledge of how they were made or where they were translated from… Hope that explains it…

You might also want to look at the difference between “Standard” and “Universal” CPlanes:

  • Standard construction planes

The construction plane of each viewport is independent from all of the other constructions planes.

  • Universal construction planes (see also: SynchronizeCPlanes)

The behavior of the construction planes in the viewports is linked. They all share the same origin and are positioned normal to each other. Moving, rotating, or otherwise changing the construction plane in one viewport, changes the construction planes in the other viewports, so the 90-degree/right angle/normal orientation of the construction planes is maintained.

If a construction plane is defined in some view, the Front view for example, and Universal mode is enabled, then the construction plane that was defined will be the Front plane of the new universal plane.

–Mitch


#5

Hi,
If I am in quad view with all 4 views open, and i set a CP in one view, the other views will change, which is logical.
I am seeing it, as redefining a new coordinate system… It is what it is doing when i create a new CP. This should actually be called a new axis system, because a construction plane is a construction plane, and should not be related to axis systems.

Whatever it is, your suggestion did not work, or you weren´t clear enough, or I did not understand, or all of them.

Thanks


(Willem Derks) #6

Hi Ravenzep

In Rhino the CP is bound to a view, changing a CP in one view will not change the CP in other views nor will the views change in any other way.

HTH
-Willem


#7

Only if you have “universal” CPlanes set, otherwise the CPlanes in each viewport are completely independent.

If universal planes are set, yes, when you set a CPlane in one viewport, it redefines the others accordingly. I recommend only to change the CPlane in the Perspective viewport, otherwise this is completely confusing.

Personally, since I like my CPlanes to remain constant and not change like that, I never use this system, only standard CPlanes. With standard CPlanes set, when you change the CPlane in one viewport, it doesn’t affect the others. So you are simply creating a “local” coordinate system in one viewport.

Every Rhino viewport has a local coordinate system associate with it, one that can be changed if you want. Top, Front, and Right each have different LOCAL coordinate systems by default. All of them have the same GLOBAL coordinate system, which is immutable.

It takes some getting used to if you are coming from some other program that works with coordinate systems in a different way.

–Mitch


#8

Thanks once again.
I ll give it a shot later and see how it goes.

Regards


#9

Right. It does work fine.
I didn´t know about Uplane and Cplane modes.

Thanks.


#10

Ravenzep,

One possible source of confusion here may be the Gumball. If you have it turned on, it appears as a local axis. For instance, when you rotate the circle you described, the Gumball will rotate with it. The Gumball is just manipulator, not really a local axis, and you can reset the Gumball axis to Cplane or World as desired. If you then change the Gumball setting to Align to Object it will align to the Normal Direction of the object, so in that sense the object normals are a local axis.