Hello everyone, I haven't being touching Houdini for 2 months now and have some troubles in understanding where to place the related texture files above on the shaders.

I've tried placing the map under the Reflect Intensity. But unsure as of what to do with the Glossiness texture map.

Need some advice on this, thanks.

Glossiness is the inverted roughness texture. Some renderers just have it the other way around. You don't need both.

I see, so in Mantra renderer, is it from Black to white (0-1) or the opposite?

Principled and Mantra Surface both use roughness. The higher the value, the rougher the material. Thats why all the dirt in your roughness texture is brighter than the clean parts.

Hi, I recently posted about something similar to this here https://www.sidefx.com/forum/topic/46543/?page=1#post-208083 [sidefx.com]

Note: When using a texture for Roughness, the slider (which you have set at 0.3) determines how much of the texture is used for the Roughness value. Set this to 1 to get the full value from the texture and you should see much more of a difference. I use Substance Painter for creating textures so I prefer to use correct Roughness maps rather than trying to tweak the sliders.

For a mix of metallic and non-metallic materials, you could use a Metallic map. This works well with the Principled shader when used in a Metal/Roughness workflow. (ie. Base Colour map, Roughness Map, Normal Map, Metallic map) The metallic map will determine which areas reflect the Base Colour (metallic) and which do not (non-metallic).

This doesn't work as well with the Mantra Surface Shader because instead, the Metallic map determines which areas use the Reflect Colour (specular colour) and which do not. One of the advantages of a metal/roughness workflow is to avoid creating Specular colour maps so I tend to use the Mantra Shader only for refractions or non-metallic materials.

hope that helps
Rob

¿ Where to place AO Ambient Occlusion texture map inside Principle Shader??
There is any slot for it. ¿?
In principledshader:
-Base Color
-Metallic
-Reflect
-Reflect Tint
-Roughness
-Anisotropi
-Anisotropi direction
-Subsurface
-Sheen
-Sheen Tint
-Coat
-Coat Roughness
-Surface Texture Settings

And…¿AO?

Somebody could upload a simple example file or link to a tuto??

Thanks in advance.

You don't use ao map, ao is baked lighting. If you want to use it as fake detail, you can multiply your diffuse color (base color) by the ao map. AO maps are for game engine renderers, where ray tracing does not occur.

Yes jsmack, its for a game engine, in this case Unreal Engine 4.
I can export all textures map automatically conected to their respective slots, except for the AO map.
I have both Houdini materials from another post with AO (occlusion VOP & takes), but non of them are exported to UE4.

Hi Bilbao,
What do you mean by “not exported to UE4”?
If you bake in Houdini you can output/bake also an ao path…

regards

Olaf

Olaf, I refer to the conections.
Houdini > Houdini Plugin for UE4 > UE4
https://www.sidefx.com/products/houdini-engine/ue4-plug-in/ [sidefx.com]

All textures are automatically conected to UE4 material slots (base color, metallic, specular, roughness, opacity, normal map.); except Ambient occlussion map.

OH, you are talking about a plugin that translates a mantra material into a unreal one. Now I understand. The plugin can probably only translate maps that are actually used by the mantra material, since AO is not used, it doesn't have any automatic mapping. The ‘bake’ outputs of the material are not applicable in this instance, as only the material inputs are considered. Maybe the plugin author could chime in on that.

Edit:

These appear to be the only documented mappings:

• Diffuse | ogl_diff, basecolor
  
• Opacity | ogl_alpha
  
• OpacityMask | ogl_opacitymap
  
• Normal | ogl_normalmap, normalTexture
  
• Specular | ogl_specmap/ogl_spec, reflect_texture/reflect
  
• Roughness | ogl_roughmap/ogl_rough, rough_texture/rough
  
• Metallic | metallic_texture / metallic
  
• Emissive | ogl_emit, emitcolor
  

The docs in question
http://www.sidefx.com/docs/unreal/_materials.html [sidefx.com]
possibly out of date for houdini 16

http://www.sidefx.com/docs/unreal/_materials.html [sidefx.com]
Thats is jsmack!
There is no mapping for the AO texture.

I think that a temporaly fix should be to attach the texture to the specular slot (normally not used in UE4), and then “manually” change the texture from specular to Ambient Occlusion inside UE4. .. But this is more workflow, not automatic.

Thanks for your time jsmack & Olaf.