Transparent ceiling that blocks light (for top-view render)?

[Anonymous]

Hello,

I've run into a bit of a problem: I'd like to render a top-down isometric view (showing the layout and surfaces of all in the worksite), but when there's no covering blocking abiant light (when I exclude it form the 3d view), everything is 'blown out' by the ambiant sunlight shining through the hole that is the no-ceiling... yet I want that light to shine in through the -windows- of the top-view, but not from above.

It seems that there is no material I can create that will both allow one to see through it -and- block ambiant light (defying the laws of physics, what), and I've tried creating a story above and creating a 'floor' there to see if that affects the render... to no avail.

Does anyone have any suggestion about how to get around this?

Thanks, best,

Josef.

PS: I even tried to make a reflective, but transparent surface (sort of a 'polariser')... no dice.

[Anonymous]

So you mean you mean that you want a isometric view with the hard shadows of the sun coming from the windows but not from above the ceiling?

Do you have outside elements too, like parking, trees, etc, that you want also the sun to affect? or is just the building?

Probably if you show us a picture of what you want it can be easier to help.

As far as I understand I don't know a way of doing that, I have never done it, and probably you will need to go to a 3D software to render, where you can tell the ceiling to not show in the 3d view.

This makes me curious let me think about it...

[Anonymous]

Hello, thank you for your reply.

No, no outside elements; just an interior view.

Here is a rendition that I managed (using directional 'artificial' light and no sunlight):

[Anonymous]

Oh! that looks great!

[Anonymous]

Thank you!

Here's another one I rendered last night: I got to there by putting a slab over the sunlight object, and a wall above that, all 'painted' in a custom matte black no-reflect surface... still getting some 'parasite' sunlight over the top, though. I think it -is- possible, though I wish there was an easier way.

It would be nice to have an object/slab setting that would tell it to 'behave' normally (reflect, block light, etc.), but just not show in the render.

[alemanda]

I'm not sure it is possible at the moment ... I wish GS implement this functionality soon ... It's a must when you do interior renderings. It is very helpful technique to have good perspective (I mean not so distorted perspective)

[Anonymous]

Hey, just an update:

I managed to get pretty well the effect I wanted, through elimnating all sunlight and replacing that with 'sun objects'.

I'm a photographer, so delved into my bag of studio techniques to come up with this: almost all the top and bottom area of the white field around the model is a 'neo-hidden' slab whose altitude is -just- above the window opening and inches away from the outer wall... the top surface is a (custom) white matte with all reflectivity turned off, and the bottom and sides are a (custom) non-reflective black matte. We use polysterene panels exactly like this in studio photography.

Directly underneath it is a directed sun object that uses 'global light' and 'in one direction only' illumination settings.

With this I got totally black wall-tops... which was initially what I wanted, but the end result seemed a bit 'stark', so I added a 'global' light around eight metres above the scene, set with 'no falloff' and 'no shadows'... that illuminated the wall-tops/moldings and cabinet-tops enough to show what they were (without leaving a black 'hole' as they were without this light).

[Anonymous]

That's great, and thanks for sharing the tricks!!

[Anonymous]

I also looked into cutting planes, but they allow light to pass through. Unless I've missed something.

It would be quite useful if they had an option to be transparent but block lighting effects... it could be used for any cut-plane view.