Topic: About Textures and Emissive Materials

[peterm]

Question via contact form/email:

"I am a designer working at ..., and my team has become very interested in the capabilities of Lumion. We are very impressed with the trial version we downloaded, but we had a couple of questions that we couldn't figure out through the forum, FAQs or video tutorials.

We understand that Lumion has very accurate texture scaling tools (especially while holding the SHIFT key), but is there any way to give an accurate dimension within Lumion to a wood flooring texture, for example? What if our client wanted us to show them options for 4in.-wide boards and 6in.-wide boards? The difference might be too small figure out with sliders while "eye-balling it".

Or do we need to bring the Lumion bitmap into Rhino or Revit, scale it there, and update the imported file with the new mapping information (Scale 0)? What is the best/recommended way?

The second question involves emissive materials. If, for example, we turn the ceiling surface in a room into an emissive material (to avoid placing lots of individual lights), can the material cast light and shadows? Or does it only appear brightly in a dark environment without casting light?

Thank you very much for your help! "

[peterm]

Hi

Thank you for your interest in Lumion.

If you have downloaded a version from the Lumion web site, then please be aware that is an older version 5.3.  We also have a newer Trial version at 6.3 that you can use to evaluate Lumion.  Refer our Knowledge Base Article: Trial or Demo Versions of Lumion.

Now, on to your questions: 

1. accurate dimension within Lumion to a wood flooring texture:
No, that is not currently possible.  There are some options to make that work:

    1a.  Real-world dimensions for textures, for example wooden boards that show the groove or cut for multiple boards, are best designed and created within an image editor or texture design tool.  From that you would then apply it in your 3D modelling application, then import to Lumion.

    1b. Some modellers will create the surfaces as individual boards with required dimensions, and that makes it easy to apply a generic wooden texture, both in the 3D modelling application, and as it imports to Lumion.
In this case any model already in Lumion can be easily updated using Reload, after the model is changed from a 4inch to 6inch board.  You can also export and import selected parts of a model, and show both options when needed.

    1c. As the model is in real world dimensions, it could be possible to simply use a measuring tool (you would need to make one) where you could place the tool next to the surface and then use the Scale slider to get an 'as close to' for the texture.

Note that all textures are Tiled textures, so non square textures are best applied in the 3D modeling application so that Lumion can read the correct UV settings for the material.

We have similar issue sometimes for ceiling tiles.


2. emissive materials:
An Emissive material is only emissive, that is it glows, but does not cast light and shadow.

Users will sometimes set the lamp or lamp holder part of the model to an Emissive value without adding Spotlights.  This then gives appearance of lights in the room.  Then use some well placed Spotlights to create some shadows.

An alternative (sometimes) is to use a texture with white parts and use the Emissive mask to brighten only those parts.  Refer our Knowledge Base Article: How do you make some parts of a material more emissive?

If you find the room is for some reason too dark, then you can also control aspects of the Shadows using a Shadow Effect.  You can also add some OmniLights or Fill Lights to brighten it.  For those, be aware that  OmniLights are general fill lights that render extremely fast.  The downside is that the light from Omni Lights pass through all objects.  It's also possible to add some additional Spotlights and use those as broad based lighting by increasing the Cone Angle up to or near maximum, so that they add soft-edge lighting and cast some shadows.

The Global Illumination Effect and HyperLight (Pro version) are also used to add additional light (bounce) to both interiors and exteriors.

You can also make use of the Nodes Feature for placing lots of lights, refer: Lumion 5.0 released.  Where there are lots of lights then make sure they are set to Speed or Memory unless Accuracy is needed.

Hope this helps answer your questions.