Environment Mapping in Lightscape (or faking it)

[Anonymous]

I wondered if anyone with particular lighscape knowledge was able to answer my query (or that someone is able to fake this)...

I have modelled a building with a fair amount of glass and I am wanting to create the effect of an environment map in the glazing so that I can have photos of the context reflected back in the glass - ie buiding X reflected in the west elevation and building Y in the south.

I have played with assgning a mapped material to a glass material's colour, however this falls down when the material actuall reflects and then ignores this colour (see image where reflection takes over and the glazing material's colour is ignored in favour of a raytraced refkection). Ideally I would like the image in the raytraced reflection to be my environment map (and for it to reflect differently on different elevations)

This would be the case of assigning an image to a diffuse channel in 3ds Max of an environment map, however I need to achieve something like this using lightscape.

Cheers

[Anonymous]

a simple solution is to reduce the reflectivity of the window material you have mapped your photo to. another is to create a billboard to provide the reflection.

[Dwight]

Make a big billboard across the street.
Make a material the size of the billboard of your context photo.
Make the context photo ripple to emulate glass irregularity.
Make the material coating the board have constant reflectance.

This is a long article in my book.

[__archiben]

it doesn't have the sophistication of dwight's solution, but you could simply use the lightworks background for rendering rather than the 'Render background with internal engine' option.

this has the effect of wrapping the background image right around you and using it for reflection: ok for skies, but when you have an image of buildings in the background that are also reflected from behind you it looks a little odd . . .

~/archiben

[Dwight]

Ben is right, but of course the background photo won't have adjacent structures in it. Use the simple solution if you don't need precision.

Not that the context photos will either, unless you've followed my site photography protocol. They are making a television show about it: CSI.
Context Shot Investigation. Get all the details from the getgo. Use a tripod.

Billboards let you precisely position prominent things like spires (as in my example).

Of course, using a constant refletion material defies shade if the billboard face falls in shade.

[Djordje]

d_a_gillespie wrote:
I wondered if anyone with particular lighscape knowledge was able to answer my query (or that someone is able to fake this)...

You of course mean LightWorks?

[Anonymous]

Yes I do mean Lightworks. I thought that there might be something outside of setting up a lightworks shader with a reflection map (eg faking it)

As far as billboards, I have tried using these, however when creating a video where it is just the building with a number of billboards around, when the camera moves, you can tell the images are just billboards.

I guess something similar to Ben's comment could be done using a panoramic image as the background with the background rendered in lightworks too. A 360 deg panoramic should deal with the issue of mapping around (although as you cannot assign a material, just an image to this I'm not as sure) - Personally I think lightworks should have in its reflectance shader parameters the option for an image to be used as a diffuse multiplier overlay with a parameter to control the impact of this image onto the raytraced reflection