tilt axis

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Dear all,

I want to tilt my roof slab. However, the tilt axis appears along the
short edge. How can I change the tilt axis so that the roof slab rotates
along the long axis?

Thanks

Ali Tanyer, MSc, PhD

Ali Murat Tanyer's picture
Joined: 2011-09-30
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Hi Ali,

I assume you're asking about a detailed-level edit.

The angle of the tilt axis is defined indirectly by the azimuth.

Adjust your surface azimuth until the "tilt axis" appears correct, then
adjust your X/Y/Z coordinates to reposition the surface. You may wish
to copy/modify the polygon being referenced if the end-result is too
wacky-looking. This is often a good time to ask yourself: is
"correcting" this shape necessary for model accuracy, or only achieving
aesthetic results?

If rectilinear, you may find it easier to define tilted roof geometries
by height/width: Change "Location: Top" (default for flat roofs coming
out of the wizards) to one of the vertex options, set Z=space height,
and go to town with the 3D view in the background to see what's going on
as you tweak the width/height/tilt variables. Reference the associated
space polygon(s) if necessary to ensure your decimal dimensions will
sync with the rest of the model.

Best of luck,

~Nick

NICK CATON, P.E.

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Joined: 2011-09-30
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Dear Nick and Others,

The advice on playing with the surface azimuth is not working. I tried 4
different azimuth angles (see attached image az1.jpeg) and in all of
them the rotation is along the short edge. I would like the rotation
along the long edge. But how to do that?

There are 2 advices on the list:
http://lists.onebuilding.org/htdig.cgi/equest-users-onebuilding.org/2009-September/002320.html
http://lists.onebuilding.org/htdig.cgi/equest-users-onebuilding.org/2010-April/004219.html

The first one (inverting the X and Y coordinates) is close to the
solution but coordinates are the mirror (see attached image az2.jpeg).
The second one does not work at all.

Any suggestions?

Thanks

Ali Murat Tanyer's picture
Joined: 2011-09-30
Reputation: 0

Folks,

I think I may have finally worked this one out.

It seems that the polygons always tilt on their local x-axis (independent of space or shell coordinate systems). I don't know how eQUEST determines the axes from the initial wizard inputs, but you can redefine polygons to force it.

I have access to CAD, so I've been recreating the polygons in CAD and twirling them around/changing the 1st vertex so that the x-axis and my intended tilt axis are the same, then inputting the new vertices back into the .inp file as a new polygon. You then have to wrestle the roof/wall back to its intended spot. Measuring off of a CAD file helps here too.

I haven't done too many, let me know if that works for others. And as noted by some very experienced users earlier, think about cost/benefit ratio before you spend lots of time on sloped roofs.

Thanks,
Wesley

Wesley S. Care's picture
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Joined: 2011-09-30
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