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My kingdom for an IES profile that points down

KurzonDaxKurzonDax Posts: 228
in Technical Help (nuts n bolts)

So I have a surface that's part of an object that needs to be emissive.  No problem there.  However, to help the realism of the scene, I want to use an IES profile on this surface.  As most know, IES profiles do not use the Y axis for verticality.  If I was working with a primitive or a native light, I'd just rotate the object/light to get the direction correct.  However, in this case, I can't rotate the whole object just for the one surface.  Is the only other solution to this to use a point or spot light placed where the emissive surface is? I'd prefer not to go down that path because the shape of the surface is somewhat important in this case.

Comments

  • mjc1016mjc1016 Posts: 15,001

    Yes, most other things use Z...

    How about creating a small plane, use the option to set the axis on the Create dialog box, turn it emissive and add the profile to it.   Position it in the correct spot on the light fixture (assuming you are trying to light a fixture).

  • KurzonDaxKurzonDax Posts: 228

    I was really hoping for a magic bullet here.  Oh well.  I will probably have to forego the use of a profile.Thanks, mjc.

     

    Hey, Daz, if you're listening... Give us some way to compensate for this without resorting to tricks or hacks.   

  • mjc1016mjc1016 Posts: 15,001

    There are a ton of thngs on the 3DL side that need all sorts of changes to get to work out right because of the axis swap...this is just one more in a long list of things that Y-up affects.

    I haven't tried it, but there are IES viewers that do some editing...maybe you can change the lobes?  What kind of profile are you wanting to use?   I've got a lot of them...there may be something with 'sideways' facing lobes in what I have...

    The swapping axis does work, but not on a complex model, that's why the use of the primitive.  It's only enabled for primitives.

  • mjc1016mjc1016 Posts: 15,001

    This is one reason I prefer using IES in Luxrender...they point correctly (or at least 'up'), just flipping the normals will make it point down, at least with Luxus.  It does the proper transform to make the world cooridinates 'correct'.

  • KurzonDaxKurzonDax Posts: 228

    Hey, sorry for the delayed response.  Forgot to subscribe to the thread.

    I ended up taking the long and complicated approach.  I split out the geometry from the rest of the object to its own and turned it 90 degrees.  I accomplished what I wanted, but as you said, another in the list of Y-up issues.  It ended up ok though as I was dumb-struck on how to handle it for a light pole I modeled that I'm about to put up on sharecg.  Sometimes I get too stuck on staring at the river to see a bridge.

    Thanks for your help.  

  • mjc1016mjc1016 Posts: 15,001
    edited February 2016

    I played around for about an hour running IES tests in Iray...and in 30 seconds did the same thing in Luxus (flipped normals after I saw it was point 'up' instead of down). 

    Post edited by mjc1016 on
  • TabascoJackTabascoJack Posts: 865
    KurzonDax said:

    I was really hoping for a magic bullet here.  Oh well.  I will probably have to forego the use of a profile.Thanks, mjc.

     

    Hey, Daz, if you're listening... Give us some way to compensate for this without resorting to tricks or hacks.   

     

    I second this!   I shouldn't have to resort to hacks like this in order to get existing models to behave correctly with IES profiles.

     

     

     

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