From 1b89d4d54190f1d4bccd1da879d2267ce4dfa47c Mon Sep 17 00:00:00 2001
From: sfan5 <sfan5@live.de>
Date: Thu, 11 Apr 2024 17:23:20 +0200
Subject: [PATCH] Simplify getBlockNodeIdMapping

since commit 0f9c78c3ebf920fac65030e66367b9940055075f nodedef->get()
will never return an entry with empty name, so we can drop the related parts.
---
 src/mapblock.cpp    | 21 +++++++--------------
 src/nameidmapping.h |  9 ++++-----
 2 files changed, 11 insertions(+), 19 deletions(-)

diff --git a/src/mapblock.cpp b/src/mapblock.cpp
index e2204f083..3985324bb 100644
--- a/src/mapblock.cpp
+++ b/src/mapblock.cpp
@@ -215,21 +215,22 @@ void MapBlock::expireIsAirCache()
 
 // List relevant id-name pairs for ids in the block using nodedef
 // Renumbers the content IDs (starting at 0 and incrementing)
+// Note that there's no technical reason why we *have to* renumber the IDs,
+// but we do it anyway as it also helps compressability.
 static void getBlockNodeIdMapping(NameIdMapping *nimap, MapNode *nodes,
 	const NodeDefManager *nodedef)
 {
-	// The static memory requires about 65535 * sizeof(int) RAM in order to be
+	// The static memory requires about 65535 * 2 bytes RAM in order to be
 	// sure we can handle all content ids. But it's absolutely worth it as it's
 	// a speedup of 4 for one of the major time consuming functions on storing
 	// mapblocks.
 	thread_local std::unique_ptr<content_t[]> mapping;
 	static_assert(sizeof(content_t) == 2, "content_t must be 16-bit");
 	if (!mapping)
-		mapping = std::make_unique<content_t[]>(USHRT_MAX + 1);
+		mapping = std::make_unique<content_t[]>(CONTENT_MAX + 1);
 
-	memset(mapping.get(), 0xFF, (USHRT_MAX + 1) * sizeof(content_t));
+	memset(mapping.get(), 0xFF, (CONTENT_MAX + 1) * sizeof(content_t));
 
-	std::unordered_set<content_t> unknown_contents;
 	content_t id_counter = 0;
 	for (u32 i = 0; i < MapBlock::nodecount; i++) {
 		content_t global_id = nodes[i].getContent();
@@ -243,21 +244,13 @@ static void getBlockNodeIdMapping(NameIdMapping *nimap, MapNode *nodes,
 			id = id_counter++;
 			mapping[global_id] = id;
 
-			const ContentFeatures &f = nodedef->get(global_id);
-			const std::string &name = f.name;
-			if (name.empty())
-				unknown_contents.insert(global_id);
-			else
-				nimap->set(id, name);
+			const auto &name = nodedef->get(global_id).name;
+			nimap->set(id, name);
 		}
 
 		// Update the MapNode
 		nodes[i].setContent(id);
 	}
-	for (u16 unknown_content : unknown_contents) {
-		errorstream << "getBlockNodeIdMapping(): IGNORING ERROR: "
-				<< "Name for node id " << unknown_content << " not known" << std::endl;
-	}
 }
 
 // Correct ids in the block to match nodedef based on names.
diff --git a/src/nameidmapping.h b/src/nameidmapping.h
index 3acb43ef1..47f424cbc 100644
--- a/src/nameidmapping.h
+++ b/src/nameidmapping.h
@@ -21,8 +21,8 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 
 #include <string>
 #include <iostream>
-#include <set>
 #include <unordered_map>
+#include <cassert>
 #include "irrlichttypes_bloated.h"
 
 typedef std::unordered_map<u16, std::string> IdToNameMap;
@@ -42,6 +42,7 @@ public:
 
 	void set(u16 id, const std::string &name)
 	{
+		assert(!name.empty());
 		m_id_to_name[id] = name;
 		m_name_to_id[name] = id;
 	}
@@ -67,8 +68,7 @@ public:
 	}
 	bool getName(u16 id, std::string &result) const
 	{
-		IdToNameMap::const_iterator i;
-		i = m_id_to_name.find(id);
+		auto i = m_id_to_name.find(id);
 		if (i == m_id_to_name.end())
 			return false;
 		result = i->second;
@@ -76,8 +76,7 @@ public:
 	}
 	bool getId(const std::string &name, u16 &result) const
 	{
-		NameToIdMap::const_iterator i;
-		i = m_name_to_id.find(name);
+		auto i = m_name_to_id.find(name);
 		if (i == m_name_to_id.end())
 			return false;
 		result = i->second;