make all Frontend children mandatory unless stated otherwise

Author: devsh

include/nbl/asset/material_compiler3/CFrontendIR.h

@@ -265,7 +265,18 @@ class CFrontendIR : public CNodePool
 					bool isBTDF;
 					// there's space for 7 more bools
 				};
-				virtual inline bool invalid(const SInvalidCheckArgs&) const {return false;}
+				// by default all children are mandatory
+				virtual inline bool invalid(const SInvalidCheckArgs& args) const
+				{
+					const auto childCount = getChildCount();
+					for (uint8_t i=0u; i<childCount; i++)
+					if (const auto childHandle=getChildHandle_impl(i); !childHandle)
+					{
+						args.logger.log("Default `IExprNode::invalid` child #%u missing!",system::ILogger::ELL_ERROR,i);
+						return true;
+					}
+					return false;
+				}
 				virtual _TypedHandle<IExprNode> getChildHandle_impl(const uint8_t ix) const = 0;
 
 				virtual inline core::string getLabelSuffix() const {return "";}
@@ -481,6 +492,7 @@ class CFrontendIR : public CNodePool
 		{
 			protected:
 				inline TypedHandle<IExprNode> getChildHandle_impl(const uint8_t ix) const override final {return ix ? (ix!=1 ? extinction:transmittance):reflectance;}
+				NBL_API bool invalid(const SInvalidCheckArgs& args) const override;
 				inline void printDot(std::ostringstream& sstr, const core::string& selfID) const override
 				{
 					sstr << "\n\t" << selfID << " -> " << selfID << "_computeTransmittance [label=\"computeTransmittance = " << (computeTransmittance ? "true":"false") << "\"]";

src/nbl/asset/material_compiler3/CFrontendIR.cpp

@@ -57,14 +57,30 @@ bool CFrontendIR::CFresnel::invalid(const SInvalidCheckArgs& args) const
 			}
 		}
 	}
-	else
+	else if (orientedImagEta)
 	{
 		args.logger.log("Oriented Imaginary Eta node of correct type must be attached, but is %u of type %s",ELL_ERROR,orientedImagEta,args.pool->getTypeName(orientedImagEta).data());
 		return true;
 	}
 	return false;
 }
 
+bool CFrontendIR::CThinInfiniteScatterCorrection::invalid(const SInvalidCheckArgs& args) const
+{
+	if (!args.pool->deref(reflectance))
+	{
+		args.logger.log("Reflectance node of correct type must be attached, but is %u of type %s",ELL_ERROR,reflectance,args.pool->getTypeName(reflectance).data());
+		return true;
+	}
+	if (!args.pool->deref(transmittance))
+	{
+		args.logger.log("Reflectance node of correct type must be attached, but is %u of type %s",ELL_ERROR,transmittance,args.pool->getTypeName(transmittance).data());
+		return true;
+	}
+	// TODO: check extinction
+	return false;
+}
+
 bool CFrontendIR::COrenNayar::invalid(const SInvalidCheckArgs& args) const
 {
 	if (!ndParams)