Optimize ABM checks.

See #7555

Cache (up to 64) node types for each active block.
Check this cache first to see whether any ABM needs to be triggered for a block.

1 files changed, 10 insertions, 0 deletions

diff --git a/src/mapblock.h b/src/mapblock.h
index 00695a94e..6b5015cab 100644
--- a/src/mapblock.h
+++ b/src/mapblock.h
@@ -114,6 +114,8 @@ public:
 		} else if (mod == m_modified) {
 			m_modified_reason |= reason;
 		}
+		if (mod == MOD_STATE_WRITE_NEEDED)
+			contents_cached = false;
 	}
 
 	inline u32 getModified()
@@ -529,6 +531,14 @@ public:
 
 	static const u32 nodecount = MAP_BLOCKSIZE * MAP_BLOCKSIZE * MAP_BLOCKSIZE;
 
+	//// ABM optimizations ////
+	// Cache of content types
+	std::unordered_set<content_t> contents;
+	// True if content types are cached
+	bool contents_cached = false;
+	// True if we never want to cache content types for this block
+	bool do_not_cache_contents = false;
+
 private:
 	/*
 		Private member variables