gistfile1.cpp

// After working on this for a few hours, here is some code to get Physical Material as a struct in c++ (it seems to be missing in the current 3ds max 2020 SDK):

// numbers taken from here: https://help.autodesk.com/view/3DSMAX/2020/ENU/?guid=GUID-57562F6A-A8A1-4A28-BAE1-0D4729411214
#define PHYSICAL_MATERIAL_CLASS_ID Class_ID(1030429932, 3735928833) 

struct PhysicalMaterial
{
	float anisoangle = 0;
	float anisotropy = 0;
	float base_weight = 0;
	float brdf_curve = 0;
	float brdf_high = 0;
	float brdf_low = 0;
	float bump_map_amt = 0;
	float clearcoat_bump_map_amt = 0;
	float coat_affect_color = 0;
	float coat_affect_roughness = 0;
	float coat_ior = 0;
	float coat_roughness = 0;
	float coating = 0;
	float diff_roughness = 0;
	float displacement_map_amt = 0;
	float emission = 0;
	float emit_kelvin = 0;
	float emit_luminance = 0;
	float metalness = 0;
	float reflectivity = 0;
	float roughness = 0;
	float scattering = 0;
	float sss_depth = 0;
	float sss_scale = 0;
	float trans_depth = 0;
	float trans_ior = 0;
	float trans_roughness = 0;
	float transparency = 0;
	int aniso_channel = 0;
	int aniso_mode = 0;
	int material_mode = 0;
	Texmap* aniso_angle_map = 0;
	Texmap* anisotropy_map = 0;
	Texmap* base_color_map = 0;
	Texmap* base_weight_map = 0;
	Texmap* bump_map = 0;
	Texmap* coat_bump_map = 0;
	Texmap* coat_color_map = 0;
	Texmap* coat_map = 0;
	Texmap* coat_rough_map = 0;
	Texmap* cutout_map = 0;
	Texmap* diff_rough_map = 0;
	Texmap* displacement_map = 0;
	Texmap* emission_map = 0;
	Texmap* emit_color_map = 0;
	Texmap* mapM0 = 0;
	Texmap* mapM1 = 0;
	Texmap* mapM10 = 0;
	Texmap* mapM11 = 0;
	Texmap* mapM12 = 0;
	Texmap* mapM13 = 0;
	Texmap* mapM14 = 0;
	Texmap* mapM15 = 0;
	Texmap* mapM16 = 0;
	Texmap* mapM17 = 0;
	Texmap* mapM18 = 0;
	Texmap* mapM19 = 0;
	Texmap* mapM2 = 0;
	Texmap* mapM20 = 0;
	Texmap* mapM3 = 0;
	Texmap* mapM4 = 0;
	Texmap* mapM5 = 0;
	Texmap* mapM6 = 0;
	Texmap* mapM7 = 0;
	Texmap* mapM8 = 0;
	Texmap* mapM9 = 0;
	Texmap* metalness_map = 0;
	Texmap* refl_color_map = 0;
	Texmap* reflectivity_map = 0;
	Texmap* roughness_map = 0;
	Texmap* scattering_map = 0;
	Texmap* sss_color_map = 0;
	Texmap* sss_scale_map = 0;
	Texmap* trans_color_map = 0;
	Texmap* trans_ior_map = 0;
	Texmap* trans_rough_map = 0;
	Texmap* transparency_map = 0;
	Point4* base_color = 0;
	Point4* coat_color = 0;
	Point4* emit_color = 0;
	Point4* refl_color = 0;
	Point4* sss_color = 0;
	Point4* sss_scatter_color = 0;
	Point4* trans_color = 0;
	bool aniso_angle_map_on = 0;
	bool anisotropy_map_on = 0;
	bool base_color_map_on = 0;
	bool base_weight_map_on = 0;
	bool brdf_mode = 0;
	bool bump_map_on = 0;
	bool coat_bump_map_on = 0;
	bool coat_color_map_on = 0;
	bool coat_map_on = 0;
	bool coat_rough_map_on = 0;
	bool coat_roughness_inv = 0;
	bool cutout_map_on = 0;
	bool diff_rough_map_on = 0;
	bool displacement_map_on = 0;
	bool emission_map_on = 0;
	bool emit_color_map_on = 0;
	bool metalness_map_on = 0;
	bool refl_color_map_on = 0;
	bool reflectivity_map_on = 0;
	bool roughness_inv = 0;
	bool roughness_map_on = 0;
	bool scattering_map_on = 0;
	bool sss_color_map_on = 0;
	bool sss_scale_map_on = 0;
	bool thin_walled = 0;
	bool trans_color_map_on = 0;
	bool trans_ior_map_on = 0;
	bool trans_rough_map_on = 0;
	bool trans_roughness_inv = 0;
	bool trans_roughness_lock = 0;
	bool transparency_map_on = 0;

	void setFloatMember(const std::wstring & name, const float f)
	{
#define SET_FLOAT(memberName) if (name == L#memberName) memberName = f; 
		SET_FLOAT(anisoangle)
		SET_FLOAT(anisotropy)
		SET_FLOAT(base_weight)
		SET_FLOAT(brdf_curve)
		SET_FLOAT(brdf_high)
		SET_FLOAT(brdf_low)
		SET_FLOAT(bump_map_amt)
		SET_FLOAT(clearcoat_bump_map_amt)
		SET_FLOAT(coat_affect_color)
		SET_FLOAT(coat_affect_roughness)
		SET_FLOAT(coat_ior)
		SET_FLOAT(coat_roughness)
		SET_FLOAT(coating)
		SET_FLOAT(diff_roughness)
		SET_FLOAT(displacement_map_amt)
		SET_FLOAT(emission)
		SET_FLOAT(emit_kelvin)
		SET_FLOAT(emit_luminance)
		SET_FLOAT(metalness)
		SET_FLOAT(reflectivity)
		SET_FLOAT(roughness)
		SET_FLOAT(scattering)
		SET_FLOAT(sss_depth)
		SET_FLOAT(sss_scale)
		SET_FLOAT(trans_depth)
		SET_FLOAT(trans_ior)
		SET_FLOAT(trans_roughness)
		SET_FLOAT(transparency)
	}



	void setIntMember(const std::wstring& name, const int i)
	{
#define SET_INT(memberName) if (name == L#memberName) memberName = i; 
		SET_INT(aniso_channel)
		SET_INT(aniso_mode)
		SET_INT(material_mode)
	}



	void setBoolMember(const std::wstring& name, const bool b)
	{
#define SET_BOOL(memberName) if (name == L#memberName) memberName = b; 
		SET_BOOL(aniso_angle_map_on)
		SET_BOOL(anisotropy_map_on)
		SET_BOOL(base_color_map_on)
		SET_BOOL(base_weight_map_on)
		SET_BOOL(brdf_mode)
		SET_BOOL(bump_map_on)
		SET_BOOL(coat_bump_map_on)
		SET_BOOL(coat_color_map_on)
		SET_BOOL(coat_map_on)
		SET_BOOL(coat_rough_map_on)
		SET_BOOL(coat_roughness_inv)
		SET_BOOL(cutout_map_on)
		SET_BOOL(diff_rough_map_on)
		SET_BOOL(displacement_map_on)
		SET_BOOL(emission_map_on)
		SET_BOOL(emit_color_map_on)
		SET_BOOL(metalness_map_on)
		SET_BOOL(refl_color_map_on)
		SET_BOOL(reflectivity_map_on)
		SET_BOOL(roughness_inv)
		SET_BOOL(roughness_map_on)
		SET_BOOL(scattering_map_on)
		SET_BOOL(sss_color_map_on)
		SET_BOOL(sss_scale_map_on)
		SET_BOOL(thin_walled)
		SET_BOOL(trans_color_map_on)
		SET_BOOL(trans_ior_map_on)
		SET_BOOL(trans_rough_map_on)
		SET_BOOL(trans_roughness_inv)
		SET_BOOL(trans_roughness_lock)
		SET_BOOL(transparency_map_on)

	}



	void setPoint4Member(const std::wstring& name, Point4* p4)
	{
		#define SET_POINT4(memberName) if (name == L#memberName) memberName = p4; 
		SET_POINT4(base_color)
		SET_POINT4(coat_color)
		SET_POINT4(emit_color)
		SET_POINT4(refl_color)
		SET_POINT4(sss_color)
		SET_POINT4(sss_scatter_color)
		SET_POINT4(trans_color)
	}



	void setTexmapMember(const std::wstring& name, Texmap* texmap)
	{
#define SET_TEXMAP(memberName) if (name == L#memberName) memberName = texmap;
		SET_TEXMAP(aniso_angle_map)
		SET_TEXMAP(anisotropy_map)
		SET_TEXMAP(base_color_map)
		SET_TEXMAP(base_weight_map)
		SET_TEXMAP(bump_map)
		SET_TEXMAP(coat_bump_map)
		SET_TEXMAP(coat_color_map)
		SET_TEXMAP(coat_map)
		SET_TEXMAP(coat_rough_map)
		SET_TEXMAP(cutout_map)
		SET_TEXMAP(diff_rough_map)
		SET_TEXMAP(displacement_map)
		SET_TEXMAP(emission_map)
		SET_TEXMAP(emit_color_map)
		SET_TEXMAP(mapM0)
		SET_TEXMAP(mapM1)
		SET_TEXMAP(mapM10)
		SET_TEXMAP(mapM11)
		SET_TEXMAP(mapM12)
		SET_TEXMAP(mapM13)
		SET_TEXMAP(mapM14)
		SET_TEXMAP(mapM15)
		SET_TEXMAP(mapM16)
		SET_TEXMAP(mapM17)
		SET_TEXMAP(mapM18)
		SET_TEXMAP(mapM19)
		SET_TEXMAP(mapM2)
		SET_TEXMAP(mapM20)
		SET_TEXMAP(mapM3)
		SET_TEXMAP(mapM4)
		SET_TEXMAP(mapM5)
		SET_TEXMAP(mapM6)
		SET_TEXMAP(mapM7)
		SET_TEXMAP(mapM8)
		SET_TEXMAP(mapM9)
		SET_TEXMAP(metalness_map)
		SET_TEXMAP(refl_color_map)
		SET_TEXMAP(reflectivity_map)
		SET_TEXMAP(roughness_map)
		SET_TEXMAP(scattering_map)
		SET_TEXMAP(sss_color_map)
		SET_TEXMAP(sss_scale_map)
		SET_TEXMAP(trans_color_map)
		SET_TEXMAP(trans_ior_map)
		SET_TEXMAP(trans_rough_map)
		SET_TEXMAP(transparency_map)

	}


};

void convertToPhysicalMaterial(Mtl* maxMtl, PhysicalMaterial & physicalMaterial)
{
	// the following is based on this code https://forums.autodesk.com/t5/3ds-max-programming/getting-parameters-and-maps-of-physical-material/td-p/7466752
	int nref = maxMtl->NumRefs();
	for (int i = 0; i < nref; i++)
	{
		ReferenceTarget* ref = maxMtl->GetReference(i);

		if (!ref)
		{
			continue;
		}

		MSTR className;
		ref->GetClassName(className);
		if (className == L"ParamBlock2")
		{
			Class_ID clsid = ref->ClassID();
			IParamBlock2* pb = dynamic_cast<IParamBlock2*>(ref);
			if (!pb)
				continue;

			const int num_param = pb->NumParams();
			for (int j = 0; j < num_param; ++j)
			{
				const ParamID id = pb->IndextoID(j);

				const ParamDef& param_def = pb->GetParamDef(id);
				PB2Value& pb2_val = pb->GetPB2Value(id, 0);

				switch (param_def.type)
				{
				case TYPE_FLOAT:
					physicalMaterial.setFloatMember(param_def.int_name, pb2_val.f);
					break;
				case TYPE_INT:
					physicalMaterial.setIntMember(param_def.int_name, pb2_val.i);
					break;
				case TYPE_BOOL:
					physicalMaterial.setBoolMember(param_def.int_name, pb2_val.i != 0);
					break;
				case TYPE_FRGBA:
					physicalMaterial.setPoint4Member(param_def.int_name, pb2_val.p4);
					break;
				case TYPE_TEXMAP:
					physicalMaterial.setTexmapMember(param_def.int_name, pb->GetTexmap(id));
					break;
				default:
					// big error
					break;
				}
			}
		}
	}

}

// And use it like this:

void useSample()
{
	INode* pNode = getSomeNode();

	Mtl* maxMtl = pNode->GetMtl();

	MSTR mtlClassName;
	maxMtl->GetClassName(mtlClassName);
	Class_ID mtlClassID = maxMtl->ClassID();
	SClass_ID mtlSuperClass = maxMtl->SuperClassID();

	if (mtlClassID == PHYSICAL_MATERIAL_CLASS_ID)
	{
		PhysicalMaterial physicalMaterial;
		convertToPhysicalMaterial(maxMtl, physicalMaterial);
	}
 }