Author Topic: Full Lightmap Solution - No Sun  (Read 3472 times)

ossosso

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Full Lightmap Solution - No Sun
« on: August 06, 2014, 11:29:48 am »
August 06, 2014, 11:29:48 am
Hi!

Into Lumion I can see is possible to use LightMap. In a simple test I've baked textures in a simple exterior scene with a plane, some objects on it and a sun light.

Once imported into Lumion I've applied the Lightmap material and loaded the textures.
All works correctly but now I have TWO shodows on the plane object: one of the baked texture and one of the Lumion SunLight.

If I set to 0 Sun Intensity the scene became all black...
Is it possible to see objects with lightmap on it and any other extra light/color influence?

If not, which is the correct workflow for which LightMap material has been intended?
Maybe during "bake texture" process should I set only GlobalIllumination, or TotalLighting avoiding shadows? I believe that baking shadows too can add realism to the scene.

Thanks a lot.

Re: Full Lightmap Solution - No Sun
« Reply #1 on: August 06, 2014, 12:46:27 pm »
August 06, 2014, 12:46:27 pm
Hi

I presume the Ambient value is set to the default of 1, and it was baked in Max to the the Self-Illumination map channel of a Standard material.  If so you should be seeing the light and shadows from the bake.

You should probably set the Sun as neutral as possible, that is Sun Height at -1, Sun Heading at 0 and Sun Brightness at 0.

This still leaves lighting in the Lumion world from the Sky and Clouds, so those can be changed as needed.

re workflow: please refer: How do I prepare Lightmaps in 3D Studio Max? 3D Studio Max: How do I export a model?

Appreciate only a test, but Lightmaps are probably best for interior scenes.  You can of course achieve a higher raytraced shadow with Baking, but you then have static shadows (OK for image renders), and Lumion is generally about a dynamic scene, especially for exteriors.

ossosso

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Re: Full Lightmap Solution - No Sun
« Reply #2 on: August 06, 2014, 02:36:54 pm »
August 06, 2014, 02:36:54 pm
Thank you Peter for your answer.

I think I've not completely understood LightMap usage.

Why should I create new lights into Lumion like the ones of 3dsmax?
I needn't, 'cause both light/gi and shadows are baked into textures.
I'd simply like to explore the model into Lumion without the interference of extra light.

Probably the workflow I've in mind is not the correct one.

The first issue regards extra light: can I switch off both Sun and Sky light source? If I put Sun Height to -1 remains a blueish color, and if I slide to 0 the sun intensity every lights became black; I suppose the slider isn't a Sun/Sky intensity, but a sort of Camera Exposure.

I can get what I wrote above if:
-Sun Height set to -1 and Sun Intensity (I call it sun intensity but I don't know the slider name, the one under the cloud amount) set to more or less 0.3, until the bluish disappear, but if I set to 0.0 everything disappear.
-LightMap Material Settings: Ambient set to 1.0 / Lightmap slider set to Anything (it doesn't affect nothing, what does it is for?) / Lightmap Multiply set around 0.7 / Depth Offset set to Anything
-LightMap Material Textures: I load the texture under the Diffuse slot, if I load it also (or only) into the other slot (lightmap) it seems nothing happens, what does this second slot is for?

I suppose I dont' understand the meaning of the slider under the LightMap material; why should I set the "Lightmap Multiply" slider to 0.7 for a "neutral" result?

But, as I said, for sure I'm trying to use this tool in the wrong way. Maybe it has been created for bake into texture only GI (and not what in 3dsmax BakeToTexture window is called "VrayCompleteMap").

Thanks again.

Re: Full Lightmap Solution - No Sun
« Reply #3 on: August 07, 2014, 07:36:13 am »
August 07, 2014, 07:36:13 am
Hi

Your right,  I previously edited my reply to remove suggestion of lights, but I think you must have been reading post at same time. 

In Build Mode you use the Weather settings there for Sun and Cloud mainly as scene defaults only and provide lighting to work in the scene.  Those settings can also be used when creating photos and movies.  For more control though you add the Sun and Cloud Effects in Photo Mode or Movie Mode.

Lightmap Settings:
 [dot]  Ambient: self-lighting of object.  Amount will depend on lighting used within Lumion, and required ambience from diffuse texturing and lighting used to render lightmap.  If use nighttime neutral lighting then Ambient needs to be very low (<0.005), if use daytime neutral lighting then Ambient needs to be at least 0.7 or up to default value of 1.
 [dot]  Lightmap: an Emissive value. 
 [dot]  Lightmap Multiply: blend of Diffuse Texture (Slot 1) and Lightmap Texture (Slot 2).  Generally needs to be high (0.7 or more) for shadows to be strong enough in scene.
 [dot]  Depth Offset:  same as other Depth Offset for materials; to control any material flickering.

Have attached some pics to help show settings etc.

Note for Lumion the render to texture is the standard Max LightingMap.