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EJS 3D coordinate system orientation of axes post and replies

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EJS 3D coordinate system orientation of axes
Cleon Teunissen
27 Posts

Returning to EJS model editing after a long hiatus I came to the disconcerting realization that I cannot remember what the orientation is of the axes of the 3D drawing panels.

Is the x,y plane the vertical plane with the z-axis front to back?
Or is the x,y plane the horizontal plane?

I'm now wondering how I was able to create simulations with 3D views in the past. :-)

As far as I can tell this is not documented in the EJS wiki. Have I overlooked documentation? If not then this is a documentation request.


Replies to EJS 3D coordinate system orientation of axes

Re: EJS 3D coordinate system orientation of axes -
Francisco Esquembre
228 Posts

Hi,

Yes, documentation always lags behind in EjsS. I always try to reply quickly to minimise this...

XY is the horizontal plane, with the X axis pointing towards you (coming out of the screen plane) by default. If you select the AXES Decoration, you can probably see this better.

The Z axis is therefore vertical by default.

Bests,

Paco



Re: EJS 3D coordinate system orientation of axes -
Cleon Teunissen
27 Posts

Yes, it was of course easy to figure it out. The AXES decoration didn't come to mind to me; I added three differently colored dots in the 3DFrame, at the respective unit vector positions (1,0,0), (0,1,0), (0,0,1).

Speaking of 3D Frame decorations, under some circumstances, when not using the EJS camera defaults, the decorations are the wrong size.

I attach a zip file, it's a zipped EJS model file. There is a 3D Frame with a sphere in it, and the decorations are too small. So: feature request: to make the decorations scalable, so that they can be adjusted to match the scene.



Re: EJS 3D coordinate system orientation of axes -
Cleon Teunissen
27 Posts

Second attempt at attaching a file (a zip file).
As stated in the previous message, under some circumstances the 3D decoration is the wrong size. Hence the feature request: to add the possibility of choosing the size of the decoration.

Attached File: ejs_3D_decoration.zip



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