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a Glare study (??)


Koper
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Any one ever done a glare study, its the same as a daylight shadow study of a building, except for it being shadows it is the suns reflection from its glass.

 

I've been tasked to show some home owners (animation) that a new building won't leave them blind during the day with all the glass panels that comes along with the building.

 

I've been looking around for a good tutorial on reflective caustics but haven't found any.

 

any thoughts would be much appreciated!

 

thanx

 

A

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You didn't mention what software you would be using for this. Revit was pointed out above, but you might also check into Ecotect or something along those lines.

 

This is not something that should be talked in Max. If you are just looking for angles where the sun reflects at a tangent and blinds you, then you might be able to do that. But if you are looking for true performance specs of a building or material, then you are going to need something that is specifically designed to deal with those issues.

 

Edit.. Actually, Ecotect might not be any better at this than Max. Here is an interesting thread.

 

http://www.ecotect.com/node/1356

 

.

Edited by Crazy Homeless Guy
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thanx, but yeah, all in max and vray, maybe if mental ray can do it then i'll go that way.

 

maybe i have to go study how the angles of reflection caustics work and try and mimic it, but then its fake which aint good.

 

I'll go through the links and see what i can come up with.

 

I think this is an interesting problem to try and solve so keep em coming.

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This sounds like one case where Maxwell or Fryrender would be good choices. They are all about physical accuracy at the expense of time. I would think you would need detailed specs from the glass manufacturer to create accurate materials though.

 

Jack

 

is Maxwell or Fryrender more accurate than MR or VRAY??? All of them are designed to be physically accurate as far as I knew...

 

could this be taken care of using trig and modelling the results to make them graphical?

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Maxwell and Fry are both "unbiased" renderers, which means they use a brute force method to calculate an image. Vray, Mental Ray, and most other engines use all kinds of clever algorithms to get the best possible image in the shortest time.

 

The downside of the unbiased approach is time. The same scene that takes Vray 30 minutes to render could take Maxwell 30 hours. I don't know about Mental Ray, but Vray actually does have an option for unbiased rendering. I haven't tried it though.

 

To grossly simplify, Vray gets 95% of the quality of Maxwell in 5% of the time.

 

Jack

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I have done one for a project recently with mental ray. Nothing good for quantitative results but good enough for illustrating the path of light. I tinted the caustics artificially for easier visual representation:

 

http://www.pfbreton.com/2009/07/nascar-hall-of-fame-daylight-simulation/

 

That is prefect, perfect perfect. good job done there.

 

Thanx quizzy. That renders super fast as well.

 

 

 

I quickly did try to do it with the vray sun and just switching on the caustics but that didn't do much.

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Well, its working beeeautiful. As the rest of the project is set in vray, I can still use my vray cams to render the caustics in mental ray. Its just a shame there is not a render elements pass for extracting the caustics.

 

I'm now just trying to render as much black as possible with the caustics multiplier set to very high in red, then picking the red channel in the render should suffice.

 

Thanx for all the input, gotta love this community ;)

 

 

oh, maybe one of the moderators can move this thread to general discussions as its not really a vray thing anymore

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pierre, nice to see that animation. funny thing is that I did not see that one, but my caustic max file attached to the post earlier looks exactly the same.. color of the caustics that is... nice coincidence...

koper, no caustic pass in MR? ahhhhh.. thats really too bad.

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okay just a little more info and a max scene attached.

 

so added to the workaround above, you want to REMOVE your MR sky map if you have that. and set the background color to black.

next, if you want your glass reflecting the caustics, just leave all settings untouched. If you dont want that, so you really want the caustics, and caustic-only.. go to your raytracing settings in the renderer tab, there you'll find Max. reflections, set that to zero.

in the scene file attached, you'll see reflections of the caustics in the glass, I've also set the caustic color back to white and upped the multiplier to 4 to get more white in there.

this b/w image you can use to alter your final image in every single way...

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