KeyShot Forum

Technical discussions => General discussion => Topic started by: wayneheim on January 17, 2015, 07:17:38 PM

Title: off center rotation of object without Animation option
Post by: wayneheim on January 17, 2015, 07:17:38 PM
Using keyshot 5.1 pro but don't have the animation addition. I have a part - like a pair of pliers and I need to pivot/rotate the one side/handle from the center nut area (but they don't connect in the center). It is maddening to try to rotate something like this from/at a specific point. Is there any way to change the rotation point without paying for the animation upgrade. I don't do animation, just product renders/stills.

Any help asap would be massively appreciated.

Wayne
Title: Re: off center rotation of object without Animation option
Post by: Rex on January 19, 2015, 09:11:20 AM
Look for this feature to be available in KeyShot 6.

Thank you
Title: Re: off center rotation of object without Animation option
Post by: wayneheim on January 19, 2015, 10:33:27 AM
Thanks but unless that is coming out soon, I'm still in the same boat.  Any help would be appreciated.

W.
Title: Re: off center rotation of object without Animation option
Post by: DriesV on January 19, 2015, 11:12:11 AM
Quote from: wayneheim on January 19, 2015, 10:33:27 AM
Thanks but unless that is coming out soon, I'm still in the same boat.  Any help would be appreciated.

W.

You could try moving your origin in CAD, so that for one handle it coincides with the center of the nut. I know of at least a few strategies to do this in SolidWorks.

Dries
Title: Re: off center rotation of object without Animation option
Post by: wayneheim on January 19, 2015, 11:20:28 AM
I was able to pretty much get it working in a very trial and error sort of way.  I made a helper object (cube) and had to move it around. Then I select both the cube and the one handle and you see the center of rotation (middle of the entire space occupied by both shapes). I then move the cube again and again till I get the center of the combined space to be where I want it to rotate it from.

Not very quick.  But to anyone who is trying this. Here is the kicker. If you then rotate the objects with the rotation helper tool, the center shifts!! Ugg, you got to start all over again.

The trick is to group the objects and then use the rotation option in the scene/position window.  There you can punch in a rotation angle and the helper object and the object retain their relationship and you can rotate each handle as many times as you want, even after rotating the entire object in the scene.

Hope this helps others.
Wayne
Title: Re: off center rotation of object without Animation option
Post by: andy.engelkemier on January 28, 2015, 09:20:35 AM
This is actually a powerpoint issue people have at all. That's right. I'm comparing the useability to powerpoint, because the solution is essentially the same.

You have two options:
In your modeling software, duplicate your object, and rotate it 180 around the pivot point you intend to have. If that's offset you may have to do that 2 more times. Basically you're creating a group. The center of your group is your pivot. This method creates a larger file, but might be easier for some.

option two, create a box or sphere at the point you want a pivot. Make sure it completely surrounds your part.

Now in Keyshot, group those objects, if they aren't already. Hide the box, or extra pieces. But when you select it, make sure you choose the parent group instead of the part. That has the correct pivot.

Now....ready for the bad news? Keyshot Doesn't remember which sub parts are hidden! So you can't use the queue to render. And you have to hide all those parts every time you open the file. So it's Super fun every time you crash and have to open it again.
Title: Re: off center rotation of object without Animation option
Post by: wayneheim on January 28, 2015, 09:29:49 AM
My helper objects stay hidden. I'm only rendering stills vs animations.

But the big key is once you get the center of rotation in the correct place by previewing it with the "rotation tool" then group the helper object with the object you want to rotate. Then select that object and numerically rotate it using the position settings in the directory on the right.  It will pivot around this new point and you can move it multiple times without the pivot point recalculating like it will do if you use the "rotation tool" to rotate the object.

W.
Title: Re: off center rotation of object without Animation option
Post by: andy.engelkemier on January 28, 2015, 09:35:56 AM
Hmmm. I bet it's using world coordinates every time then?

If that's true, you could just use a sphere to do it. As you rotate a cube, the world bounding box changes. But a sphere keeps the same bounding, no matter it's rotation.
Title: Re: off center rotation of object without Animation option
Post by: wayneheim on January 28, 2015, 09:44:17 AM
The world bounding box is not changing when you enter it numerically for some reason. That's what make multiple rotations work. It will change if you use the widget to rotate vs doing it numerically.
Title: Re: off center rotation of object without Animation option
Post by: andy.engelkemier on January 28, 2015, 09:49:27 AM
I'm sure that makes sense to Someone.
Title: Re: off center rotation of object without Animation option
Post by: wayneheim on January 28, 2015, 02:31:27 PM
If you have a part you want to rotate at a particular point - non-standard like the tip. Make a "helper object" and then move the helper around till the rotation widget (the color circles with arrows) shows the center of rotation in the correct spot when you have both the object you want to rotate and the helper selected.

Then group the two objects. Then on the right side where your scene assets are listed, click on the object you wish to rotate within the group.

Then, on the right at the bottom half of the side panel, click position tab. If you use the values here to rotate your image, the pivot point stays in the same spot no matter how many times you rotate it (using only these numbers). Now if you move the object with the 3d move tool, you should still be able to go back to the scene list, select the part, and then rotate it or unrotate it using the numbers under position for that object.