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Reverse light

Anonymous
Not applicable
Hi mates,
I was searching the documenation and also this awesome board but couldn't find a solution for this:

I want to design shining floor in a bathroom.
I need a reverse light tool but can't find any - nor any kind of parameter.
I mean I need a light that will shine from down - up, from floor to ceiling

There is a lightning PANEL but only with traditional light.
Please help me,
regards
Mar
30 REPLIES 30
Andy Thomson
Advisor
a cone is fine, just a cone with 89.999 degree walls would be nice!

Andy Thomson, M.Arch, OAA, MRAIC
Director
Thomson Architecture, Inc.
Instructor/Lecturer, Toronto Metropolitan University Faculty of Engineering & Architectural Science
AC26/iMacPro/MPB Silicon M2Pro
Anonymous
Not applicable
Andy,
Looking at the parameter list of the object "strip lamp 10",
I notice that some of the parameters are hidden.
If you un-hide them you might be able to get the
control you are talking about.

Again looking at the code for the LIGHT command
it appears that one can make a cylindrical light source
if the radius is set to the cylinder radius you want and
the two angles, one of which is hidden in this object,
are set to zero.
Peter Devlin
Dwight
Newcomer
Peter wrote:
code for a light source type object in the GDL
GS does not have a truly diffuse light source
so apparently we are stuck with some form of cone shape.
Peter Devlin
Partly true, partly not.

My book spends a lot of time demonstrating making and controlling diffuse light using the light cone light source. Exercises in the book indicate precisely how to illuminate an entire room with soft light coming from only one light source. This information remains current from Archicad 9 to Archicad 10.

The "light cone down" is the energy source used by most of the "lamps" along with the magical "wall light diffuse."

In doing the travelling seminars, I've been expanding this part of the lecture to make upp for simplifications in sunlighting techniques available in Archicad 10. The seminar is coming to the Bay area, Los Angeles and Orange County at the end of January.

Buying the book will immediately give you the power to cammand this light, or you could experiment for a week on your own like I did.

The attached image is one of the light cone development exercises I did in discovering how to control soft llighting.
Dwight Atkinson
Dwight
Newcomer
Furthermore, an entire room can be illuminated by just one light source.

Things work better if you use a little fill light. In this example, there's a golden "general lilght" to the left of the camera.
Dwight Atkinson
Dwight
Newcomer
The wall light indirect actually has a "Diffuse" setting, but it is hidden at the bottom of a long list of parameters. This is overly modest and certainly is a quality posessed by the sister of the girl you are dating but don't find out about it until after the engagement.

I think Graphisoft really messed up naming this light source and by placing the diffuse control at the bottom. Joke on us. Haha.

The attached image shows a naked wall light indirect with "Show light cone" "ON." This exposes the vertical cone that is normally even more diffuse. You'll find this source in wall lamps.
show litecone.jpg
Dwight Atkinson
Dwight
Newcomer
And the last thing I am giving away tonite in a vain attempt to clear the last copies of my book prior to Christmas is the way to fool the eye into thinking you have a light emitting surface when you don't. And that is by making your strip lights have a "Constant" reflectance shader and for wacky extra colors, an attenuated emission shader. This is how we make thousands of light fixtures in a building without incurring a useless rendering time hit.

For instance, the attached has no interior lights.

Some of the lads have alluded to things in the book that solve this problem, particularly not expecting the lamp to be the light source. Keep them separate.
Dwight Atkinson
Dwight
Newcomer
Okay, one more, but it is a promo for my upcoming California Seminars. Further to the llight cone issue, there's several ways to illuminate large interior spaces with a mere hanful of lights. Here's a test room with just three lights.
three colors.jpg
Dwight Atkinson
Anonymous
Not applicable
Hello Dwight,
I guess what I meant by the term "diffuse light source" would be
a light source that is like a radiant panel or like a giant CRT screen
that covers an entire wall or an entire floor.
The effect of such a lighting device on walls, ceilings, and objects
would be that there would be no fall off edges, no matter how diffuse,
and there would be no shadows in corners.
Are we using this term in the same sense or differently ?
Thanks,
Peter Devlin
Dwight
Newcomer
That would be your windolite.

Or overlapping light cones that extend past the walls.

All of these need to be modulated with a general light source, but it is free in the rendering time because it casts no shadows.
Dwight Atkinson
Anonymous
Not applicable
Hello Dwight,
When you say "That would be your windolite. "
are you referring to the "window light" object in the lightworks folder ?
Thanks,
Peter Devlin