topic Re: Shadow of the sun in elevation in Modeling

Shadow of the sun in elevation

johanes — Wed, 08 Dec 2021 07:12:54 GMT

I have two constructions: one existing and other proposed. We set the North (Options -> Project Preferences -> Set Project North) and I considered the Sun position on 21.12.2022, the Eastern time (07:53). By opening a 3D layout window of the 2 constructions, looking at the Southeast Directorate, we can see the shadow of the proposed construction left on the southern facade of the existing construction. Now if I position a facade (elevation), oblique and looking on constructions all from the southeast, we can see the same shadow left on the southern facade of the existing construction. I now place a facade (elevation) that "looks" perpendicular to the southern facade of the existing construction. When viewing the southern facade of the construction - surprise - no shadow appears on the facade. I tried all the variants of the elevation settings and I was unable to make the shadow on the facade. The sun exists, the proposed construction exists and the shadow of the construction proposed on the facade of the existing construction should also appear.
Can anyone tell me where the "secret" is? Or Archicad can't display the shadow of an object on another object if the latter is "looked" from a certain direction?
Please forgive my English ... Thanks !

Re: Shadow of the sun in elevation

Red — Tue, 07 Dec 2021 18:17:05 GMT

Possibly post an image of both elevation settings that you show. I want to guess it is a setting. It is easy to overlook them. I have done it myself before.

Re: Shadow of the sun in elevation

Barry Kelly — Wed, 08 Dec 2021 00:47:12 GMT

The shadow can only be cast by elements in the view.

Your elevation has excluded those adjacent blocks - therefore they will not cast a shadow.

Barry.

Re: Shadow of the sun in elevation

johanes — Wed, 08 Dec 2021 14:59:01 GMT

Here are the settings of the two elevations.

Re: Shadow of the sun in elevation

johanes — Wed, 08 Dec 2021 15:01:31 GMT

Here are the settings of the two elevations.

Re: Shadow of the sun in elevation

Red — Wed, 08 Dec 2021 18:58:14 GMT

I didn't see the last image in the original post the first go-around, but like Barry mentioned, it needs to be with the same elevation to cast a shadow.

Re: Shadow of the sun in elevation

Red — Wed, 08 Dec 2021 19:00:57 GMT

One thought... Would it still cast the shadow if the item was on a layer and turned off? I haven't tested it, but I assume it wouldn't.

Re: Shadow of the sun in elevation

Red — Wed, 08 Dec 2021 19:04:13 GMT

This should work though... Create a 3D Document looking straight on the side of the building with the shadows turned on.

Re: Shadow of the sun in elevation

johanes — Thu, 09 Dec 2021 12:16:50 GMT

But this is not logical because the sun did not disappear and the construction exists (behind me), and the shadow should appear.

Re: Shadow of the sun in elevation

johanes — Thu, 09 Dec 2021 12:24:43 GMT

That's how Barry says, but I do not find logical this thing because the sun did not disappear, and the construction exists (behind me).

Re: Shadow of the sun in elevation

johanes — Thu, 09 Dec 2021 13:15:28 GMT

I understand what you mean ... That is, to move the elevation tool in the back, on the opposite side of the proposed construction and then to "hide" the proposed construction. I tried ... It does not work ...

Re: Shadow of the sun in elevation

johanes — Thu, 09 Dec 2021 14:06:50 GMT

I don't understand well what you want to say, but I tried to create a 3D document, with shadows turned on, with perpendicular view on the sunny facade of the proposed building. Only part of the shadow is seen, the other side being hidden by the building. From side view the shadow is not seen on the facade that interests me (southern facades of existing construction).

Re: Shadow of the sun in elevation

Barry Kelly — Fri, 10 Dec 2021 01:00:37 GMT

Archicad only calculates what you see on screen when calculating shadows.

Otherwise it would be much slower than it is now.

Not much point in calculating what you can't see - except in this case.

I remember reading something about casting shadows like this.

I will search to see if I can find anything.

Barry.

Re: Shadow of the sun in elevation

Barry Kelly — Fri, 10 Dec 2021 01:05:54 GMT

This is the post I was thinking of...

https://community.graphisoft.com/t5/Wishes-forum/shadows-on-adjoining-properties-elevation/m-p/77524/highlight/true#M7111

Make sure when you copy, you have the 2D window as Vectorial and not OpenGL/Harware Acceleration.

Only works for Vectorial.

It is a manual solution and you will have to repeat if the shadow changes for any reason.

Barry.