Minor fixes around yield and compact node (#333)

* Fix yield node to return hasField() according to its map

* Require a field that is actually used by the compact node

* Fix case when hasField is called before yield node has finished executing

Author: msz-rai

src/graph/NodesCore.hpp

@@ -84,7 +84,7 @@ struct CompactByFieldPointsNode : IPointsNodeSingleInput
 	void enqueueExecImpl() override;
 
 	// Node requirements
-	std::vector<rgl_field_t> getRequiredFieldList() const override { return {IS_HIT_I32, IS_GROUND_I32}; }
+	std::vector<rgl_field_t> getRequiredFieldList() const override { return {fieldToCompactBy}; }
 
 	// Point cloud description
 	bool isDense() const override { return true; }
@@ -399,8 +399,15 @@ struct YieldPointsNode : IPointsNodeSingleInput
 	// Node requirements
 	std::vector<rgl_field_t> getRequiredFieldList() const override { return fields; }
 
+	// Point cloud description
+	bool hasField(rgl_field_t field) const override
+	{
+		// The `results` map cannot be relied on because the hasField() may be called before the node has finished executing.
+		return std::find(fields.begin(), fields.end(), field) != fields.end();
+	}
+
 	// Data getters
-	IAnyArray::ConstPtr getFieldData(rgl_field_t field) override { return results.at(field); }
+	IAnyArray::ConstPtr getFieldData(rgl_field_t field) override;
 
 	HostPinnedArray<Field<XYZ_VEC3_F32>::type>::Ptr getXYZCache() { return xyzHostCache; }
 

src/graph/YieldPointsNode.cpp

@@ -16,6 +16,7 @@
 
 void YieldPointsNode::setParameters(const std::vector<rgl_field_t>& fields)
 {
+	results.clear();
 	if (std::find(fields.begin(), fields.end(), RGL_FIELD_DYNAMIC_FORMAT) != fields.end()) {
 		throw InvalidAPIArgument("cannot yield field 'RGL_FIELD_DYNAMIC_FORMAT'"); // TODO: Yeah, but dummies are OK?
 	}
@@ -33,3 +34,11 @@ void YieldPointsNode::enqueueExecImpl()
 		                           xyzHostCache->getCount() * xyzHostCache->getSizeOf(), cudaMemcpyDefault, getStreamHandle()));
 	}
 }
+
+IAnyArray::ConstPtr YieldPointsNode::getFieldData(rgl_field_t field)
+{
+	if (!results.contains(field)) {
+		throw std::runtime_error("Field data is not ready yet. It was requested without waiting for results.");
+	}
+	return results.at(field);
+}