diff --git a/terrain/voxel_lod_terrain.cpp b/terrain/voxel_lod_terrain.cpp
index 20612cb..b73b2d7 100644
--- a/terrain/voxel_lod_terrain.cpp
+++ b/terrain/voxel_lod_terrain.cpp
@@ -527,6 +527,8 @@ void VoxelLodTerrain::_process() {
 		VoxelProviderThread::InputData input;
 
 		input.priority_block_position = viewer_block_pos;
+		input.use_exclusive_region = true;
+		input.exclusive_region_extent = get_block_region_extent();
 
 		for (unsigned int lod_index = 0; lod_index < get_lod_count(); ++lod_index) {
 			Lod &lod = _lods[lod_index];
@@ -598,6 +600,9 @@ void VoxelLodTerrain::_process() {
 	// Send mesh updates
 	{
 		VoxelMeshUpdater::Input input;
+		input.priority_position = viewer_block_pos;
+		input.use_exclusive_region = true;
+		input.exclusive_region_extent = get_block_region_extent();
 
 		for (unsigned int lod_index = 0; lod_index < get_lod_count(); ++lod_index) {
 			Lod &lod = _lods[lod_index];
diff --git a/terrain/voxel_mesh_updater.cpp b/terrain/voxel_mesh_updater.cpp
index 61de07c..eb7c612 100644
--- a/terrain/voxel_mesh_updater.cpp
+++ b/terrain/voxel_mesh_updater.cpp
@@ -73,7 +73,7 @@ void VoxelMeshUpdater::push(const Input &input) {
 			if (index) {
 				// The block is already in the update queue, replace it
 				++replaced_blocks;
-				_shared_input.blocks.write[*index] = block;
+				_shared_input.blocks[*index] = block;
 
 			} else {
 
@@ -88,6 +88,12 @@ void VoxelMeshUpdater::push(const Input &input) {
 		}
 
 		_shared_input.priority_position = input.priority_position;
+
+		if (input.use_exclusive_region) {
+			_shared_input.use_exclusive_region = true;
+			_shared_input.exclusive_region_extent = input.exclusive_region_extent;
+		}
+
 		should_run = !_shared_input.is_empty();
 	}
 
@@ -209,10 +215,12 @@ static void scale_mesh_data(VoxelMesher::Output &data, float factor) {
 		// so you won't trash performance with pointless allocations
 		surface[Mesh::ARRAY_VERTEX] = Variant();
 
-		PoolVector3Array::Write w = positions.write();
-		int len = positions.size();
-		for (int j = 0; j < len; ++j) {
-			w[j] = w[j] * factor;
+		{
+			PoolVector3Array::Write w = positions.write();
+			int len = positions.size();
+			for (int j = 0; j < len; ++j) {
+				w[j] = w[j] * factor;
+			}
 		}
 
 		// Thank you
@@ -282,9 +290,15 @@ void VoxelMeshUpdater::thread_sync(int queue_index, Stats stats) {
 		// Get input
 		MutexLock lock(_input_mutex);
 
-		_input.blocks.append_array(_shared_input.blocks);
+		append_array(_input.blocks, _shared_input.blocks);
+
 		_input.priority_position = _shared_input.priority_position;
 
+		if (_shared_input.use_exclusive_region) {
+			_input.use_exclusive_region = true;
+			_input.exclusive_region_extent = _shared_input.exclusive_region_extent;
+		}
+
 		_shared_input.blocks.clear();
 
 		for (unsigned int lod_index = 0; lod_index < MAX_LOD; ++lod_index) {
@@ -307,12 +321,39 @@ void VoxelMeshUpdater::thread_sync(int queue_index, Stats stats) {
 		_output.blocks.clear();
 	}
 
+	// Cancel blocks outside exclusive region
+	//int dropped_count = 0;
+	if (_input.use_exclusive_region) {
+		for (int i = 0; i < _input.blocks.size(); ++i) {
+			const InputBlock &ib = _input.blocks[i];
+
+			Rect3i box = Rect3i::from_center_extents(_input.priority_position >> ib.lod, Vector3i(_input.exclusive_region_extent));
+
+			if (!box.contains(ib.position)) {
+
+				Vector3i shifted_block_pos = _input.blocks.back().position;
+
+				_input.blocks[i] = _input.blocks.back();
+				_input.blocks.pop_back();
+
+				_block_indexes[ib.lod].erase(ib.position);
+				_block_indexes[ib.lod][shifted_block_pos] = i;
+
+				//++dropped_count;
+			}
+		}
+	}
+
+	//	if (dropped_count > 0) {
+	//		print_line(String("Dropped {0} blocks to mesh from thread").format(varray(dropped_count)));
+	//	}
+
 	if (!_input.blocks.empty() && needs_sort) {
 		// Re-sort priority
 
 		SortArray<VoxelMeshUpdater::InputBlock, BlockUpdateComparator> sorter;
 		sorter.compare.center = _input.priority_position;
-		sorter.sort(_input.blocks.ptrw(), _input.blocks.size());
+		sorter.sort(_input.blocks.data(), _input.blocks.size());
 	}
 }
 
diff --git a/terrain/voxel_mesh_updater.h b/terrain/voxel_mesh_updater.h
index 0dd2a47..0caa3d5 100644
--- a/terrain/voxel_mesh_updater.h
+++ b/terrain/voxel_mesh_updater.h
@@ -20,8 +20,10 @@ public:
 	};
 
 	struct Input {
-		Vector<InputBlock> blocks;
-		Vector3i priority_position;
+		std::vector<InputBlock> blocks;
+		Vector3i priority_position; // In LOD0 block coordinates
+		int exclusive_region_extent = 0;
+		bool use_exclusive_region = false;
 
 		bool is_empty() const {
 			return blocks.empty();
diff --git a/terrain/voxel_provider_thread.cpp b/terrain/voxel_provider_thread.cpp
index 367edb2..b0862f6 100644
--- a/terrain/voxel_provider_thread.cpp
+++ b/terrain/voxel_provider_thread.cpp
@@ -42,10 +42,15 @@ void VoxelProviderThread::push(const InputData &input) {
 
 		// TODO If the same request is sent twice, keep only the latest one
 
-		_shared_input.blocks_to_emerge.append_array(input.blocks_to_emerge);
-		_shared_input.blocks_to_immerge.append_array(input.blocks_to_immerge);
+		append_array(_shared_input.blocks_to_emerge, input.blocks_to_emerge);
+		append_array(_shared_input.blocks_to_immerge, input.blocks_to_immerge);
 		_shared_input.priority_block_position = input.priority_block_position;
 
+		if (input.use_exclusive_region) {
+			_shared_input.use_exclusive_region = true;
+			_shared_input.exclusive_region_extent = input.exclusive_region_extent;
+		}
+
 		should_run = !_shared_input.is_empty();
 	}
 
@@ -112,10 +117,12 @@ void VoxelProviderThread::thread_func() {
 					stats.min_time = time_taken;
 					stats.max_time = time_taken;
 				} else {
-					if (time_taken < stats.min_time)
+					if (time_taken < stats.min_time) {
 						stats.min_time = time_taken;
-					if (time_taken > stats.max_time)
+					}
+					if (time_taken > stats.max_time) {
 						stats.max_time = time_taken;
+					}
 				}
 
 				EmergeOutput eo;
@@ -137,8 +144,9 @@ void VoxelProviderThread::thread_func() {
 			}
 		}
 
-		if (_thread_exit)
+		if (_thread_exit) {
 			break;
+		}
 
 		// Wait for future wake-up
 		_semaphore->wait();
@@ -183,12 +191,18 @@ void VoxelProviderThread::thread_sync(int emerge_index, Stats stats) {
 		// Get input
 		MutexLock lock(_input_mutex);
 
-		_input.blocks_to_emerge.append_array(_shared_input.blocks_to_emerge);
-		_input.blocks_to_immerge.append_array(_shared_input.blocks_to_immerge);
+		append_array(_input.blocks_to_emerge, _shared_input.blocks_to_emerge);
+		append_array(_input.blocks_to_immerge, _shared_input.blocks_to_immerge);
 		_input.priority_block_position = _shared_input.priority_block_position;
 
+		if (_shared_input.use_exclusive_region) {
+			_input.use_exclusive_region = true;
+			_input.exclusive_region_extent = _shared_input.exclusive_region_extent;
+		}
+
 		_shared_input.blocks_to_emerge.clear();
 		_shared_input.blocks_to_immerge.clear();
+		_shared_input.use_exclusive_region = false;
 	}
 
 	stats.remaining_blocks = _input.blocks_to_emerge.size();
@@ -204,12 +218,32 @@ void VoxelProviderThread::thread_sync(int emerge_index, Stats stats) {
 		_output.clear();
 	}
 
+	// Cancel blocks outside exclusive region
+	//int dropped_count = 0;
+	if (_input.use_exclusive_region) {
+		for (int i = 0; i < _input.blocks_to_emerge.size(); ++i) {
+			const EmergeInput &ei = _input.blocks_to_emerge[i];
+
+			Rect3i box = Rect3i::from_center_extents(_input.priority_block_position >> ei.lod, Vector3i(_input.exclusive_region_extent));
+
+			if (!box.contains(ei.block_position)) {
+				_input.blocks_to_emerge[i] = _input.blocks_to_emerge.back();
+				_input.blocks_to_emerge.pop_back();
+				//++dropped_count;
+			}
+		}
+	}
+
+	//	if (dropped_count > 0) {
+	//		print_line(String("Dropped {0} blocks to load from thread").format(varray(dropped_count)));
+	//	}
+
 	if (!_input.blocks_to_emerge.empty()) {
 		// Re-sort priority
 
 		SortArray<EmergeInput, BlockPositionComparator> sorter;
 		sorter.compare.center = _input.priority_block_position;
-		sorter.sort(_input.blocks_to_emerge.ptrw(), _input.blocks_to_emerge.size());
+		sorter.sort(_input.blocks_to_emerge.data(), _input.blocks_to_emerge.size());
 	}
 }
 
diff --git a/terrain/voxel_provider_thread.h b/terrain/voxel_provider_thread.h
index 5efce25..c40fc79 100644
--- a/terrain/voxel_provider_thread.h
+++ b/terrain/voxel_provider_thread.h
@@ -1,8 +1,9 @@
 #ifndef VOXEL_PROVIDER_THREAD_H
 #define VOXEL_PROVIDER_THREAD_H
 
-#include "../math/vector3i.h"
+#include "../math/rect3i.h"
 #include <core/resource.h>
+#include <vector>
 
 class VoxelProvider;
 class VoxelBuffer;
@@ -23,9 +24,11 @@ public:
 	};
 
 	struct InputData {
-		Vector<ImmergeInput> blocks_to_immerge;
-		Vector<EmergeInput> blocks_to_emerge;
-		Vector3i priority_block_position;
+		std::vector<ImmergeInput> blocks_to_immerge;
+		std::vector<EmergeInput> blocks_to_emerge;
+		Vector3i priority_block_position; // In LOD0 block coordinates
+		int exclusive_region_extent = 0;
+		bool use_exclusive_region = false;
 
 		inline bool is_empty() {
 			return blocks_to_emerge.empty() && blocks_to_immerge.empty();
diff --git a/util/utility.h b/util/utility.h
index 3736711..8a8e245 100644
--- a/util/utility.h
+++ b/util/utility.h
@@ -103,4 +103,9 @@ inline bool is_mesh_empty(Ref<Mesh> mesh_ref) {
 	return false;
 }
 
+template <typename T>
+inline void append_array(std::vector<T> &dst, const std::vector<T> &src) {
+	dst.insert(dst.end(), src.begin(), src.end());
+}
+
 #endif // HEADER_VOXEL_UTILITY_H