From 0125ba82e8b94461894a9628dea6552c0bbfa38d Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?V=C3=ADt=20=C5=A0efl?= Date: Mon, 17 May 2021 22:32:30 +0200 Subject: [PATCH] Fix: Do not send vehicles towards incomplete PF nodes YAPF could end up in a situation where it sets the best intermediate node to a node whose construction is never finalized (i.e. it is never added to the open list). The content of the node would be overwritten in the next round, potentially sending the vehicle to an unwanted location. --- src/pathfinder/yapf/yapf_base.hpp | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/src/pathfinder/yapf/yapf_base.hpp b/src/pathfinder/yapf/yapf_base.hpp index 41c38ab34d..c548cfd97f 100644 --- a/src/pathfinder/yapf/yapf_base.hpp +++ b/src/pathfinder/yapf/yapf_base.hpp @@ -252,9 +252,9 @@ public: return; } - if (m_max_search_nodes > 0 && (m_pBestIntermediateNode == nullptr || (m_pBestIntermediateNode->GetCostEstimate() - m_pBestIntermediateNode->GetCost()) > (n.GetCostEstimate() - n.GetCost()))) { - m_pBestIntermediateNode = &n; - } + /* The new node can be set as the best intermediate node only once we're + * certain it will be finalized by being inserted into the open list. */ + bool set_intermediate = m_max_search_nodes > 0 && (m_pBestIntermediateNode == nullptr || (m_pBestIntermediateNode->GetCostEstimate() - m_pBestIntermediateNode->GetCost()) > (n.GetCostEstimate() - n.GetCost())); /* check new node against open list */ Node *openNode = m_nodes.FindOpenNode(n.GetKey()); @@ -267,6 +267,7 @@ public: *openNode = n; /* add the updated old node back to open list */ m_nodes.InsertOpenNode(*openNode); + if (set_intermediate) m_pBestIntermediateNode = openNode; } return; } @@ -292,6 +293,7 @@ public: /* the new node is really new * add it to the open list */ m_nodes.InsertOpenNode(n); + if (set_intermediate) m_pBestIntermediateNode = &n; } const VehicleType * GetVehicle() const