Materials incredibly flat, visually

I am no expert in materials, so don’t worry about stating the obvious in a reply.

At the moment, I am content to merely have objects that have some RGB coloration, but with some visual depth which is so far lacking.

I need some guidance and perhaps need to write a script to tweak my .mtl files as my art tool provides them.

Here is a htvery short video showing the present look.

Here is the overview:

  1. My 3D work is done in Rhino3D v5.0 (beta for Mac), outputting meshes as Wavefront .obj/.mtl file pairs
  2. I see that JME3 does not care for my .mtls in exactly the format Rhino outputs them. Each one loaded generates a log warning: “com.jme3.scene.plugins.MTLLoader readLine WARNING: Unknown statement in MTL! tf” One such MTL file that generates this warning is:



newmtl Gray_Steel

Ka 0.5020 0.5020 0.5020

Kd 0.4824 0.4941 0.5490

Ks 1.0000 1.0000 1.0000

Tf 0.0000 0.0000 0.0000

d 1.0000

Ns 5.027


3. the MTL file above (for a metal doorway on a metal ship) is a good example of a material that has a reasonable COLOR for me, but whose appearance in the world is unacceptably flat… you simply cannot see the edges of the hatch.

4. My world has essentially two lights at the moment: an AmbientLight with a .4f,.4f,.4f intensity and an overhead DirectionalLight with 1f,1f,1f intensity

Now, I can guess that I should write a script to pluck out the “Tf 0.0000 0.0000 0.0000” line in each MTL file, but what other things should I be doing so that these objects appear a little more real? I do not see a lot of online documentation of these file formats even though I can infer Ka, Kd and Ks refer to ambient, diffuse and specular colors.

Will it help if I give these objects a texture map? Should I have some other form of light in my world? I have not tried point lights or others, but will eventually be moving toward a dynamic sky if that modifies what sort of suggestion you’d offer.

I do not wish to get into the business of mapping out UL coordinates on my models just yet (I intend to offload art to another person at some point).


Do the models have normals and tangents?

I uploaded the hatch’s .obj and .mtl file to here

Based on a Wikipedia page on the file format, the hatch (at least) and I suspect all my objects have normals.

Generally, Rhino3D is a NURBS modeler… its support for meshes is meager. If you can provide a hint to what I presently have, it may prove helpful


well no tangents then use the tangntbinominalgenerator (obj does not support tangents)

(it will give you an exception when no normals are ther)

The model is flat.

All the Z coordinates are around -0.01 to 0.01

Everything is relative, right? I use a meter as my world unit.

The same visual flatness occurs at an scale here.

Noting the comment that .obj does not support tangents (which is news to me), can someone just tell me one to three alternative toolsets that provide a fully supported artpath for JME3?


OgreXML is the way.

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Thanks Normen… in the meantime I found an incredible improvement by adding a second DirectionalLight coming in with lower intensity and directed more sideways: (1f, -.2f, 1f) BIG WIN there – the uninteresting colors at least now show the geometry more clearly.