Topic: alpha channel and opacity in lumion ?

[gonzohot]

Hi !

How to configure a material with an opacity (alpha channel) ?

Does the diffuse material must contain opacity (like tga or tif files) or have we to put it in the second texture channel as an opacity map ?

I haven't figurate out how to achieve this untill now: can you help me please ?

[mischa]

You can use pngs with a transparency channel included. If you put this texture in max in the material it will be automatically be cutout in lumion. I don t know ho exactly you can the achieve the same effect directly in the material editor in lumion, but I think it must work the same way.

[gonzohot]

ok, thanx !

it work with TGA maps but look strange because of the lake of 2sided material ( i tried on a cube).

[Morten]

"Double-sided materials with support for transparency maps" has been added to the Functionality Wish List (This will become a sticky post soon)

[mbe]

Does Lumion support shadows for alphamaps too? Like a metal fence? Or is the alphampa just displayed as a black shadow?

[Morten]

Yes, alpha maps including shadows are supported in Update 1 Release Candidate 4 (Currently only available to paying customers – the demo version of Lumion will be updated when Update 1 Final is ready for release). The Standard material basically allows you to use alpha maps, e.g. as part of a 32-bit texture, and a slider allows you to choose whether you want to use the alpha channel as a reflection map or as a transparency map (clip).

Please note that Lumion uses a threshold to convert greyscale alpha maps to pure white/pure black, so metal fences are perfectly feasible but all edges will be hard.

[Brian Hengelsberg]

Morton,  i have exported a model out of sketchup with the two-sided textures radio button selected and have gotten the below result.

[Morten]

That's very encouraging, Brian – thanks for posting it

Artur is in charge of importing/exporting but in my capacity as a complete SketchUp novice I'm pleased to see that it seems to support this feature at the export end.

Unfortunately we'll have to keep the feature request on the wish list though as other applications like 3DS Max require that you add double-sided polygons manually. Unless one of you guys knows how to automate this?

[mbe]

Thanks for the information. It's harder and harder to keep my finger away from the purchase button.

[Brian Hengelsberg]

I suggest you purchase....been simply fantastic to work in Lumion, and the staff has been extremely helpful.

[Aaron]

Just bumping this one back in since I was wondering;

 

-Is the import double-sided polygon import issue from 3dsMax solely dependend on the importer not offering this functionality?

 

Could this be remedied in part for instance from a shader-perspective? It should be possible to create a 2-sided shader right? Just as long as both sides would have the need for the same material (for instance leaves, metal fences, latticework etc.)

[Morten]

You can indeed turn off culling both in DirectX and in an HLSL shader while rendering specific objects; this switch essentially just ensures that all polygons of a model always face the camera. However, the question is how Lumion's shadow system is affected by faces that are not truly double-sided but just facing the camera.

 I'm sure Ferry knows though