KHR_Materials warning

artlake · February 7, 2023, 11:27pm

I made a charecter with makehuman exported to fbx then exported a gltf from that fbx in blender then i added to jme i got this error i also used some charcters from sketchfab i got same error too

WARNING: Could not find loader for extension KHR_materials_specular
Feb 08, 2023 2:47:25 AM com.jme3.scene.plugins.gltf.CustomContentManager readExtension
WARNING: Could not find loader for extension KHR_materials_ior
Feb 08, 2023 2:47:25 AM com.jme3.scene.plugins.gltf.CustomContentManager readExtension
WARNING: Could not find loader for extension KHR_materials_specular
Feb 08, 2023 2:47:25 AM com.jme3.scene.plugins.gltf.CustomContentManager readExtension
WARNING: Could not find loader for extension KHR_materials_ior
Feb 08, 2023 2:47:26 AM com.jme3.scene.plugins.gltf.CustomContentManager readExtension
WARNING: Could not find loader for extension KHR_materials_specular
Feb 08, 2023 2:47:26 AM com.jme3.scene.plugins.gltf.CustomContentManager readExtension
WARNING: Could not find loader for extension KHR_materials_ior
Feb 08, 2023 2:47:26 AM com.jme3.scene.plugins.gltf.CustomContentManager readExtension
WARNING: Could not find loader for extension KHR_materials_specular
Feb 08, 2023 2:47:26 AM com.jme3.scene.plugins.gltf.CustomContentManager readExtension
WARNING: Could not find loader for extension KHR_materials_ior
Feb 08, 2023 2:47:26 AM com.jme3.scene.plugins.gltf.CustomContentManager readExtension
WARNING: Could not find loader for extension KHR_materials_specular
Feb 08, 2023 2:47:26 AM com.jme3.scene.plugins.gltf.CustomContentManager readExtension
WARNING: Could not find loader for extension KHR_materials_ior
Feb 08, 2023 2:47:26 AM com.jme3.scene.plugins.gltf.CustomContentManager readExtension
WARNING: Could not find loader for extension KHR_materials_specular
Feb 08, 2023 2:47:26 AM com.jme3.scene.plugins.gltf.CustomContentManager readExtension
WARNING: Could not find loader for extension KHR_materials_ior
Feb 08, 2023 2:47:26 AM com.jme3.scene.plugins.gltf.CustomContentManager readExtension
WARNING: Could not find loader for extension KHR_materials_specular
Feb 08, 2023 2:47:26 AM com.jme3.scene.plugins.gltf.CustomContentManager readExtension
WARNING: Could not find loader for extension KHR_materials_ior
Feb 08, 2023 2:47:26 AM com.jme3.scene.plugins.gltf.CustomContentManager readExtension
WARNING: Could not find loader for extension KHR_materials_specular
Feb 08, 2023 2:47:26 AM com.jme3.scene.plugins.gltf.CustomContentManager readExtension
WARNING: Could not find loader for extension KHR_materials_ior

pspeed · February 7, 2023, 11:29pm

Error = bad, must deal with.

Warning = you might care, you might not.

If your model loads and looks ok then don’t worry. If your model does not load or does not look ok then post that… since the warning may or may not have anything to do with that.

artlake · February 7, 2023, 11:34pm

no model load with no materal just plain model

pspeed · February 8, 2023, 1:12am

So, to rephrase your question for anyone trying to help:
“I made a charecter with makehuman exported to fbx then exported a gltf from that fbx in blender then i added to jme and they fail to load any material. i also used some charcters from sketchfab i got same problem. Here is an example of what they look like when loaded (insert picture here). I don’t know if it’s related but I get a bunch of these warnings (insert warnings from above). I’m using version (insert version JME or SDK or whatever)”

Please fill in the blanks.

Ali_RS · February 8, 2023, 7:03am

Note that afaik JME only supports loading pbrMetallicRoughness, KHR_materials_pbrSpecularGlossiness, and KHR_materials_unlit materials.

Edit:

For using pbrMetallicRoughness make sure the model is using the “Principled BSDF” node in Blender before exporting to gltf.

carpenter · February 8, 2023, 7:52am

imugur images don’t appear to me
So pbrMetallicRoughness is the default converted to pbrlighting, KHR_materials_pbrSpecularGlossiness must be converted to phong lighting, and KHR_materials_unlit must converted to unshaded material… right?

Ali_RS · February 8, 2023, 8:12am

No, it uses Spec gloss pipeline of PBRLighting

github.com

jMonkeyEngine/jmonkeyengine/blob/aaabd104771019e1a627696a98f5de5794c3c4cc/jme3-core/src/main/resources/Common/MatDefs/Light/PBRLighting.j3md#L45-L51


      
          // For Spec gloss pipeline
          Boolean UseSpecGloss
          Texture2D SpecularMap
          Texture2D GlossinessMap
          Texture2D SpecularGlossinessMap
          Color Specular : 1.0 1.0 1.0 1.0
          Float Glossiness : 1.0

Right

You can find those extension loaders here:

Ali_RS · February 8, 2023, 8:27am

By the way, I did a quick google search and found out they have an extension (KHR_materials_common) to support common Phong material.

github.com

KhronosGroup/glTF/blob/main/extensions/1.0/Khronos/KHR_materials_common/README.md

# KHR\_materials\_common

## Contributors

* Tony Parisi, WEVR, [@auradeluxe](https://twitter.com/auradeluxe), <mailto:tparisi@gmail.com>

## Status

Draft (not ratified yet)

## Dependencies

Written against the glTF draft 1.0 spec.

## Overview

This extension defines a set of common materials and lights for use with glTF. 

glTF does not define a lighting model, instead relegating shading of visuals to GLSL shader code defined within techniques in the glTF file. For many use cases, it is desirable to shade visuals with commonly understood and implemented shading techniques, such as Blinn and Lambert.

This file has been truncated. show original

In case someone is interested to create a loader for KHR_materials_common in JME we would welcome the contribution.

Edit:
Oops, this seems to be only for Gltf v1, not v2!

artlake · February 14, 2023, 2:50am

Hey, Sorry for late update I had several problem, I didn’t have light probe, and also model had problems i use modo mainly so i found the way to the problem in this video

it is for mixamo but pretty much applicable to makehuman models too, also in blender by changing opaque to alpha hashed you can make it work.
and also i found some tools to change specular workflow to metalic if you needed ever,
https://gltf.report/ you upload model to here it tells it need to change spec to metalic then export and also this nodejs tool:

# install
npm install --global @gltf-transform/cli

# convert
gltf-transform metalrough input.glb output.glb

@Ali_RS can i use pbr models with phong material in case for android dev what i do??

Ali_RS · February 14, 2023, 4:49am

Note, PBR should work on Android as well technically but performance might be a problem.

You can convert the PBR material to Phong material. This is how I do it in my asset-convert tool:

    private Material convertToPhongMaterial(Material pbr) {
        Material phong = new Material(assetManager, Materials.LIGHTING);
        phong.setName(pbr.getName());
        phong.setBoolean("UseMaterialColors", true);

        phong.setTexture("DiffuseMap", pbr.getParamValue("BaseColorMap"));
        phong.setColor("Diffuse", pbr.getParamValue("BaseColor"));

        if (pbr.getParamValue("NormalMap") != null) {
            phong.setTexture("NormalMap", pbr.getParamValue("NormalMap"));
        }

        if (pbr.getParamValue("EmissiveMap") != null) {
            phong.setTexture("GlowMap", pbr.getParamValue("EmissiveMap"));
            phong.setColor("GlowColor", pbr.getParamValue("Emissive"));
        }

        phong.setColor("Ambient", ColorRGBA.White);
        phong.setColor("Specular", ColorRGBA.Black);
        phong.setFloat("Shininess", 0);  // [0,128]
        phong.setBoolean("VertexLighting", true);

        phong.getAdditionalRenderState().setFaceCullMode(pbr.getAdditionalRenderState().getFaceCullMode());
        phong.getAdditionalRenderState().setBlendMode(pbr.getAdditionalRenderState().getBlendMode());

        Float alpha = pbr.getParamValue("AlphaDiscardThreshold");
        if (alpha != null && alpha > 0) {
            phong.setFloat("AlphaDiscardThreshold", alpha);
        }
        return phong;
    }

artlake · February 14, 2023, 4:52am

wow thank you