Alternate ISO "default" View

[dgschaefer]

WF4, M220

I need to create an alternate view that is essentially like the default isometric view, but starting with a different front view, if that makes sense.  I remember a long time ago seeing angles to rotate from a front view to get to default, can anyone tell me how to do that?

Thanks,

--

[RandyJones]

On 02/06/14 16:30, Doug Schaefer wrote:
>
> WF4, M220
>
> I need to create an alternate view that is essentially like the default isometric view, but
> starting with a different front view, if that makes sense. I remember a long time ago seeing
> angles to rotate from a front view to get to default, can anyone tell me how to do that?
>

Starting from the front view do this:
+- 45 deg about vertical
+- 35 4/15 deg about horizontal

Doing all the combinations of +- 45 about vertical and then +- 35 4/15 about horizontal will give
you all the possible isometric views.

> Thanks,
>
> *--*
>
> *Doug Schaefer*|

[mlocascio]

This is good advice. That's how we had to do it at Cummins Diesel.

[jstone]

I remember having this lying around. See attached for various view orientations.

Thanks,

jef

[wfalco]

as someone said....I remember old way of dynamically rotating about an
edge.

[TomU]

Those numbers don't seem to agree with the out-of-the-box "Trimetric" view. Looking at the front view I need to tip the model forward (horizontal axis) 51.57 degrees and then rotate left (vertical axis) 22.91 degrees to match the existing trimetric view.

I use derivatives of these values for the user defined default orientation to get "Z" pointing up (world CS) instead of at the screen from a front view. (-38.43 = 51.57 - 90)
[cid:image001.png@01CF23DE.509E7EB0] [cid:image005.jpg@01CF23DF.663FCC50]

I hate the way this comes setup out of the box. In my mind the Z axis should be coming out of the top plane, not the front plane.
[cid:image004.png@01CF23DF.66362F60]

[MikeFoster]

The exact numbers are in radians.

From a front view rotate about the horizontal .9 radians (51.5662...deg) and then rotate about the vertical -.4 radians (-22.9183...deg).

Mike Foster
ATK


[cid:image004.jpg@01CF23C9.8B1065A0]

[kimndave9]

For those who still care:

To get a right elevation angle of alpha and a left elevation of beta, starting with the alpha edge at zero and the beta edge directly into the screen, there is one rotation about the vertical axis followed by one rotation about the horizontal axis.

The vertical rotation angle = atan(sqrt(tan(alpha)/tan(beta) ))

The horizontal rotation angle = asin(sqrt(tan(alpha)*tan(beta) ))

Excel formulas, using a cell named alpha and another named beta:

H rotation =DEGREES(ATAN(SQRT(TAN(RADIANS(alpha))/TAN(RADIANS(beta)))))

V rotation =DEGREES(ASIN(SQRT(TAN(RADIANS(alpha))*TAN(RADIANS(beta)))))

For alpha = 30, beta = 30, Isometric,

vertical rotation = 45 = atan(sqrt(1)) (because alpha = beta, tan(alpha)=tan(beta))

horizontal rotation = 35.264389682755 (you have a calculator...)

For alpha = 15, beta = 30, (typical, but not unique) Trimetric,

vertical rotation = 34.26465 and some degrees

horizontal rotation = 23.161231226046 and some degrees