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Hi there folks and friends,


at the moment, i am checking different ways on how to get a correct LED light,

here you see my test file:



rendering with a glowing material makes the render a bit quicker, but i don't have that photometric light

that comes with an ies file.


so waht is your suggestion on an LED-stripe that you can buy from OSRAM and so on.

The one's you attatch on the lower side of your kitchen furniture or tv shelf.

Like use a ies-file and use a lot of lights in a row?

Is there a passibility to use ies-files with arealights? or line lights?


Really looking forward to your comments on this one,

and thanks in advance!


Bildschirmfoto 2017-04-12 um 12.00.27.png

Bildschirmfoto 2017-04-12 um 12.00.41.png

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I would strongly recommend a line light or a glow texture. Either a solid colour or one a bit like the one I have uploaded if you want to try and get the effect of the individual chips along a tape. I really wouldn't bother using what could be hundreds of separate lights unless you have an awful lot of time on your hands waiting for it to render.


The model on the left has a texture applied to an extruded rectangle the same shape as a piece of LED tape, the one on the right uses a line light.


PS. If anybody out there could give me a bit of guidance on how to fix the "splotchyness" then I would be really grateful!


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  • Vectorworks, Inc Employee

Line Lights are splotchy and there isn't much we can do to fix it. The object is considered to be deprecated in most cases and I don't think it will be getting any love anytime soon. 

Some of the splotch can also come from the environment. Renderworks doesn't place an artificial "room" around objects like a lot of other renderers do, similarly to the infinite floor and sky you see in some other modeling programs, so sometimes even though you set 8 bounces, the photons tracked from the light source only bounces once then flies off toward an area with no geometry, never to return to bounce a second time or more. In my testing it also seems that Soft Shadows, Environment Lighting and Indirect Lighting quality settings all directly affect the splotches in addition to just the number of bounces, but I want to test more to lock that down as a clear yes/no for the training materials.

That said, I still get some splotch when I use Glow as the only light source, I can work around it by having duplicates of the same glowing object right near each other to increase the glow but that's covering things up. Still trying to track that down as it didn't always used to happen.

I'm doing a segment on LED light for the Summit, I find a lot of it is really the color choice, since usually like most types of light an LED is noticeable by its spectrum before anything, being significantly different from phosphorescent (easy to get accidentally when playing with Glow textures) incandescent or fluorescent, for instance. Often I can use the same base light object or glow texture and as long as I get the source color right, the effect pops right out and its just a matter of adjusting brightness. I used to try and go by the color temperature rating on the hardware tech specs for the bulb/fixture, but I find it to be a bit easier to just use the color picker and then eyedropper the color from an image of the type of light i want, usually that gets me in the ballpark and then minor tweaks get what i want from there.

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Thanks for this post Jim. It's useful to understand the effect of colour on the light objects themselves and I'll definitely experiment further.


As a theatre lighting designer, I often like to render single sources to explain the effect of light on a piece of scenery, actor or set and also to show directors what might be possible. For that reason I often run in to the splotchiness problem. Would a good idea be to enclose the set or stage if you will in a kind of bounce surface and then use a camera to "see in" or is there an HDRI background that might be useful. (I've often wondered what the Spotlight Curvy Dome background is meant to be for.



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  • Vectorworks, Inc Employee

I don't THINK that HDRI backgrounds will bounce light from sources within the file, however you can also use them to emit environment lighting which can also keep splotches to a minimum without having to manually add more light objects or turning on Ambient lighting which can look kind of washed out.

You don't necessarily need to use a Renderworks camera to get inside a room or box though (I tend to avoid using them unless I want to use the Camera Effects, their controls and rules are a bit wonky as many has reported elsewhere), I usually just use the Walkthrough tool in perspective and then save a view inside the box/room so I can get back to it quickly from top/plan or other orthogonal elevation views.

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Is it the case that the artefacts would be improved if we could increase the sampling and smoothing (between the sampled areas). Without access to these controls there is a lot of trial and error?


also I think we may overuse glow as a kind of catch all when an area light 'should' be the better option



Edited by barkest
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  • Vectorworks, Inc Employee

Yes, for instance you can sort of "fix" line lights and Area Lights by stacking more than one in the same exact spot (duplicate without offset), but it can change it's end result literally each time you refresh the render so I don't mess with that much.

I think Area Lights could be improved to provide more of what is needed, as Glow being used as described above is absolutely a workaround to emulating some very common real world source of light. Normally Glow is only needed when you need to be looking directly at the light, when it isn't in the scene or is occluded behind other geometry, then in most other rendering software you'd go with an Area light or that softwares equivalent of that light type. 


The main issue with Line lights is due to the weird halfway point we are between 2D and 3D with some geometry which is a whole can of worms on it's own. We could likely aim some work at Area lights so that they filled this need, exposing control as you mentioned to the density of light "points" across the surface of the area and allow for control over the randomness or grid spacing of these points. Also, maybe alter how they appear in OpenGL, as they often seem to emit WAY more light in OpenGL than they do in Renderworks modes compared to other light objects. I've been meaning to do a closer study on how this is accomplished in other applications and writing up wishes for the real world use cases like LED bulbs/strips which now see heavy usage in both architectural and event planning circles.

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2 hours ago, Luis M Ruiz said:

add a single light source and turn it off, let the glow do the job of illuminating the scene.


@Luis M Ruiz- can you explain this more clearly? I'm not sure I follow how adding a light source and turning it off will have an effect on the Glow texture illuminating the scene. Thanks.

Edited by rDesign
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4 minutes ago, rDesign said:

can you explain this more clearly? I'm not sure I follow how adding a light source and turning it off will have an effect on the Glow texture illuminating the scene. Thanks.


For glow to work you need to have a light source in the scene even if that light source is turned off. I assume this is what he means. By adding the single light you are switching off the VW default light.



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  • Vectorworks, Inc Employee

If you have no light objects within a document, you will get Default lighting which can mess with the appearance of your renders. This is like Ambient lighting but it is always on UNLESS a light object of any kind is present in the document, but without a light object, Glow textures alone do not shut off Default lighting since the light from a Glow texture only appears when you have Indirect Lighting enabled in your render style.

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10 minutes ago, JimW said:

Yes. Which looks really weird in some cases:


Ambient on, default on:

Ambient off, default on:

Ambient off, default off: 


 Could you add what conditions are needed to achieve each of these to your original post (eg. View>Set Lighting Options>Ambient Off, No light objects present which I assume is your second example)? Are the conditions different depending on whether you're in the design layers or in a sheet layer viewport? I've always found lighting options a bit confusing because they are accessed in random ways (eg. when you click on lighting options for a Sheet Layer Viewport it takes you to edit a Renderworks Style instead of overriding the Renderworks style so you're essentially editing all viewports with that style). Adding this info to your images above and perhaps a set of sheet layer viewports showing the same would be a great Knowledge Base article on lighting.



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  • Vectorworks, Inc Employee

Ambient On, Default On is the normal state of a new blank document in Vectorworks before any lighting options are altered or any light objects added.

Ambient Off, Default On is what happens when you have no light objects, but have manually disabled Ambient lighting in the render style or in Set Lighting Options for the document and is the state that Luis' tip is designed to avoid.

Ambient Off, Default Off is what you get when you add a light object, but turn it off, and also have Ambient lighting disabled in lighting options. This is a "perfect" darkness which if you were inside a room, would be pitch black, and then the Glow textures would be the only light source. If you dont add the light object and turn it off, you get the fake Default lighting which often washes the Glow effect out or alters the intended color.

Will do well as a kbase article, will do!

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  • Vectorworks, Inc Employee
Just now, barkest said:

Its worth noting that the default light has a direction which I believe is the top left as you look at your monitor. (happy to be corrected)

Yep! It always comes from the upper left-ish direction regardless of your view, it's source doesn't have a physical location relative to the documents North or Rotated Plan or anything like that.

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  • 1 year later...

I haven't read everything above... I just wanted to add some 2 x 4 fluorescent / LED light fixtures to my project.  So I experimented with point lights and lamp materials and area lights in a test file.  The area light seemed to work quite well (Screenshot 03).  But then, not so much in my project file (Screenshot 04).  I think the lights are on because of the shadows, but, for whatever reason, nobody's home, as the lights themselves don't even begin to look like they're on.  So, after a good amount of time trying to figure it all out, I end up here:

  And, finally, using a glow texture, not only do things work, but, I'm impressed with just how well they work!  (Screenshot 07).  So... thanks for the video, Jim!

03-Area Light Success-02.png

04- Area Light Failure-1707-087W.png

07-Glow Texture Success-1707-087.png

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