In the viewer, the model looks great. I then bring it into the scene and it looks great. But I want to change the material programmatically. Yet this makes it look ugly. It's a physically based light model and a metallic material. Yet renders like a relatively flat phong. The detail of the other maps is there. The color is just flat and off.
To eliminate all other variables, I started applying my programmatic material right after creating the node. The material is intended to be the exact same as the one I set in the viewer. Yet I get the same ugly result when I set it to the programmatically created version.
Then I only changed the diffuse contents. And this looks great. Hopefully this isn't a stupid question as I can't find any similar complaints. But what parameter is being set in the viewer that I am missing in the SCNMaterial?
The following is my attempt to copy all the settings from my viewer and repeat it in code. Nothing has really changed anything from just setting the usual content values:
let material = SCNMaterial()
material.lightingModel = .physicallyBased
let matScale: Float = 1.0///25.4
material.isDoubleSided = false
material.diffuse.contents = UIImage(named: "basecolor.png")
//material.diffuse.contentsTransform = SCNMatrix4MakeScale(matScale, matScale, matScale)
material.diffuse.wrapS = .repeat
material.diffuse.wrapT = .repeat
material.diffuse.mipFilter = .nearest
material.diffuse.magnificationFilter = .linear
material.diffuse.minificationFilter = .linear
material.diffuse.mappingChannel = 0
material.diffuse.maxAnisotropy = 1.0
material.metalness.contents = UIImage(named: "scuffed_metalic.png")
material.metalness.wrapS = .repeat
material.metalness.wrapT = .repeat
material.metalness.mipFilter = .nearest
material.metalness.magnificationFilter = .linear
material.metalness.minificationFilter = .linear
material.metalness.mappingChannel = 0
material.metalness.maxAnisotropy = 1.0
material.roughness.contents = UIImage(named: "scuffed_roughness.png")
material.roughness.wrapS = .repeat
material.roughness.wrapT = .repeat
material.roughness.mipFilter = .nearest
material.roughness.magnificationFilter = .linear
material.roughness.minificationFilter = .linear
material.roughness.mappingChannel = 0
material.roughness.maxAnisotropy = 1.0
material.normal.contents = UIImage(named: "scuffed_normal.png")
material.normal.wrapS = .repeat
material.normal.wrapT = .repeat
material.normal.mipFilter = .nearest
material.normal.magnificationFilter = .linear
material.normal.minificationFilter = .linear
material.normal.mappingChannel = 0
material.normal.maxAnisotropy = 1.0
material.metalness.intensity = 1.0
material.roughness.intensity = 1.0//0.0//0.3
material.normal.intensity = 1.0
material.diffuse.intensity = 1.0
material.multiply.contents = UIColor.white
material.multiply.intensity = 1.0
material.transparent.contents = UIColor.white
material.transparent.intensity = 1.0
material.clearCoatNormal.contents = UIColor.white
material.clearCoatNormal.intensity = 1.0
material.locksAmbientWithDiffuse = true
material.emission.contents = UIColor.black
material.emission.intensity = 1.0
material.selfIllumination.contents = UIColor.black
material.selfIllumination.intensity = 1.0
material.clearCoatRoughness.contents = UIColor.black
material.clearCoatRoughness.intensity = 1.0
material.displacement.contents = UIColor.black
material.displacement.intensity = 1.0
material.transparencyMode = .default
material.shininess = 1.0
material.fresnelExponent = 0.0
material.cullMode = .back
material.blendMode = .alpha
material.writesToDepthBuffer = true
material.readsFromDepthBuffer = true
material.locksAmbientWithDiffuse = true
material.isLitPerPixel = true
Hmm, it's hard to say based off of the info provided here. It would be better to have a full, focused example project that demonstrates the issue. I recommend that you request technical support for this issue, as that will provide a better format to getting the info needed to answer this question.
