Preventing light coming through a section-cut

[flipya]

Hi peeps,

I can't imagine noone has ever asked this here, but I couldn't find it through search so here goes:

I'm trying to render a topview sectioncut of a house, but I want to see only the light coming through the windows, not through the actual cut. Tried making a temporary ceiling and mapping an empty .png to that, which didn't work. Painting the underside of said .png a solid color did nothing either. Is there a way to do this?

Merci bien for any help or suggestions.

Philip

[Fletch]

bon jour Philip!

well, even in SketchUp, the section cuts do not allow this functionality.

The only thing I can think of is to place a plane some meters above your building positioned and sized so that it casts shadows onto the model without blocking sunlight falling through the windows...

[flipya]

Merci bien for your answer Fletch.

In SU it is possible to fake it by just placing the .png-ceiling a few mms below the cut as seen here

SCF-shadow.JPG (30.09 KiB) Viewed 12905 times

But I take it from your answer that there's no setting in Twilight or adjustments of the .png that will render this accordingly... Too bad

EDIT: your suggestion of placing a plane between sun and model is an option, but takes a lot of tinkering to get right on bigger models (and won't work when I animate the sun's trajectory). Is this a functionality that we could expect in a future update or version?

[Fletch]

hmm... the engine would need to support such functionality. Twilight is a way to bring the engine into SketchUp seemlessly, while improving ease of use, tight integration with SU, giving it a nice user interface, etc. We shall have to see what the future holds for the functionality of the engine.

[shura]

its a bit tricky to do, but with a projector you can fake any light/shadow casting. depends on the complexity of the geometry that casts shadows. as you have to create the bitmap for projection, you might ask yourself why not paint it into the render directly. can say more when at home...
cheers
alex

[shura]

ok, this is a method how to modify shadows from SU and get them into the TWL render via projection. sorry, no soft shadows here. Not sure if this is a solution for your problem... but a funny trick to fake lighting into a render. (did a real installation like this, light coming out of a door frame leaning to a solid wall)
gotta get up early, hope what you see here is self-explaining enough:

[shura]

...

[xrok1]

this could be done if the cast shadows was made to work independently of the alpha for generic materials. or if someone could create a shadow caster material.(kind of a reverse sky portal )

OT PS, could the material reset be moved from the templates>generic>reset to a button some place more convenient please.

[Gaieus]

Maybe... If Twilight (and Kerky) could use double sided materials where light can come out from somewhere (a room) but cannot go in. Like in V-ray with which Thomthom made these renders:
http://forums.sketchucation.com/viewtop ... 81&t=22423