Materials FAQ

This happens because the user who uploaded the MXM to the material gallery placed the textures in a folder relevant only to their machine, so on your machine MXED won't be able to find the textures. To fix this:

• Go to the folder where you downloaded the MXM and double-click it to open it in MXED.

• MXED pops up a dialog asking you to locate the textures used in the material

• Navigate to the folder where the textures are located and choose the missing texture. If other textures used in a material are located in the same folder, MXED will continue searching in that folder for the other missing textures.

• After you have made sure all the textures are found (go through each BSDF in each Layer of the material to make sure), click the Save & Close button (the little CD icon) in MXED to save the MXM with the new texture paths. 

• Verify that all the textures are found for the MXM by double-clicking the MXM to open it in MXED again. No missing textures dialog should appear.

MXED/Maxwell Render/Maxwell Studio will look in the following paths to find the textures of a material:

• in the same folder where the MXM is located
  
  
• in a 'textures' subfolder where the MXM is located
  
  
• in the project folder (ie where the MXS file is located)
  
  
• in the texture paths specified in Maxwell Render/ Maxwell Studio preferences. To set these paths, go to:
  • File>Preferences>Paths (Maxwell Render)
  • File>Preferences>Materials>Textures (Maxwell Studio)

From a physical point of view, the index of refraction is not just a plain number; it is derived from a complex calculation to define the refractive index at one particular wavelength. This is the calculation: 
Refraction at a particular wavelength = Nd + K.i

The Nd represents the refractive index, which is the well-know concept of Index of Refraction we often use. The K is the extinction coefficient: the amount of absorption loss when an electromagnetic wave propagates through a material. This is usually confused with the Abbe, but it is not in fact related to this. K is related to the extinction of the wave.

The use of the K value is optional. It should be used when creating more accurate metals and you don't want to use an IOR file or an IOR file does not exist for that metal. To find the Nd and K values of common substances, please see the Luxpop site. In the wavelength box (nm) enter a wavelength of 589.

The improvements in the Maxwell Render version 2 material system allow you to create better, more complex, and faster materials. Version 1.x materials are compatible with version 2, but a small number of version 1.x materials (and therefore scenes) may not look entirely correct. We recommend to re-do as many version 1.x materials in version 2 as possible to make them into materials of a far superior quality. 

The only materials that can present difficulties are SSS materials and Clipmap materials.

The new SSS system in V2 is better integrated into the general BSDF structure, making it more intuitive and easier to configure. As the new SSS model is slightly different to the old one, your old SSS materials might appear slightly different when rendered in the new version.

To get them to look the same again, you will have to raise your Scattering Coefficient to a higher value.