reset chunks allow to refresh chunk client side + report.

src/main/java/carpet/fakes/ThreadedAnvilChunkStorageInterface.java

@@ -3,8 +3,9 @@ package carpet.fakes;
 import net.minecraft.util.math.ChunkPos;
 
 import java.util.List;
+import java.util.Map;
 
 public interface ThreadedAnvilChunkStorageInterface
 {
-    void regenerateChunkRegion(List<ChunkPos> requestedChunks);
+    Map<String, Integer> regenerateChunkRegion(List<ChunkPos> requestedChunks);
 }

src/main/java/carpet/mixins/ThreadedAnvilChunkStorage_scarpetChunkCreationMixin.java

@@ -18,6 +18,7 @@ import net.minecraft.util.thread.ThreadExecutor;
 import net.minecraft.world.chunk.Chunk;
 import net.minecraft.world.chunk.ChunkStatus;
 import net.minecraft.world.chunk.WorldChunk;
+import net.minecraft.world.storage.RegionFile;
 import org.spongepowered.asm.mixin.Final;
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.Shadow;
@@ -25,6 +26,9 @@ import org.spongepowered.asm.mixin.injection.At;
 import org.spongepowered.asm.mixin.injection.Inject;
 import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
 
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.HashSet;
@@ -84,10 +88,40 @@ public abstract class ThreadedAnvilChunkStorage_scarpetChunkCreationMixin implem
             world.getServer().execute( () -> CHUNK_GENERATED.onChunkGenerated(world, chunk) );
     }
 
-    @Override
-    public void regenerateChunkRegion(List<ChunkPos> requestedChunks)
+    private boolean chunkExists(ChunkPos chpos, Map<String, RegionFile> regionCache)
     {
+        String currentRegionName = "r." + chpos.getRegionX() + "." + chpos.getRegionZ() + ".mca";
+        if (regionCache != null && regionCache.containsKey(currentRegionName))
+        {
+            RegionFile region = regionCache.get(currentRegionName);
+            if (region == null) return false;
+            return region.hasChunk(chpos);
+        }
+        Path regionPath = world.getDimension().getType().getSaveDirectory(
+                world.getSaveHandler().getWorldDir()
+        ).toPath().resolve("region");
+        Path regionFilePath = regionPath.resolve(currentRegionName);
+        File regionFile = regionFilePath.toFile();
+        if (!regionFile.exists())
+        {
+            if (regionCache != null) regionCache.put(currentRegionName, null);
+            return false;
+        }
+        try
+        {
+            RegionFile region = new RegionFile(regionFile, regionPath.toFile());
+            if (regionCache != null) regionCache.put(currentRegionName, region);
+            return region.hasChunk(chpos);
+        }
+        catch (IOException ignored) { }
+        return true;
+    }
 
+    @Override
+    public Map<String, Integer> regenerateChunkRegion(List<ChunkPos> requestedChunks)
+    {
+        Map<String, Integer> report = new HashMap<>();
+        report.put("requested_chunks",requestedChunks.size());
         //flushning all tasks on the thread executor so all futures are ready - we don't want any deadlocks
         mainThreadExecutor.runTasks(() -> mainThreadExecutor.getTaskCount() == 0);
         // save all pending chunks
@@ -104,20 +138,21 @@ public abstract class ThreadedAnvilChunkStorage_scarpetChunkCreationMixin implem
             if (chunk != null && chunk.getStatus() != ChunkStatus.EMPTY)
                 loadedChunks.add(pos);
         }
-        CarpetSettings.LOG.error("Area has "+requestedChunks.size()+" chunks");
-        CarpetSettings.LOG.error("Area has "+loadedChunks.size()+" loaded chunks");
+        report.put("loaded_chunks", loadedChunks.size());
 
         Map<ChunkPos,ChunkStatus> targetStatus = new HashMap<>();
+        Map<String, RegionFile> regionCache = new HashMap<>();
         for (ChunkPos pos: requestedChunks)
         {
-
+            if (!chunkExists(pos, regionCache)) continue;
             Chunk chunk = world.getChunk(pos.x, pos.z, ChunkStatus.EMPTY, true);
             if (chunk == null || chunk.getStatus() == ChunkStatus.EMPTY)
                 continue;
             //unloaded areas can have unknown skirt chunk area
             targetStatus.put(pos, loadedChunks.contains(pos)?chunk.getStatus():ChunkStatus.STRUCTURE_STARTS);
         }
-        CarpetSettings.LOG.error("Area has "+targetStatus.size()+" chunks for removal");
+        regionCache.clear();
+        report.put("affected_chunks", targetStatus.size());
 
 
         for (ChunkPos chpos : targetStatus.keySet())
@@ -128,8 +163,7 @@ public abstract class ThreadedAnvilChunkStorage_scarpetChunkCreationMixin implem
             int currentLevel = ThreadedAnvilChunkStorage.MAX_LEVEL;
             if (chunkHolder != null)
             {
-                //CarpetSettings.LOG.error("current_level: "+chunkHolder.getLevel());
-                currentLevel = chunkHolder.getLevel();
+                currentLevel = chunkHolder.getLevel()-1;
                 //method_20458(id, chunkHolder); // saving chunk // skipping entities etc
                 Chunk chunk = null;
                 try
@@ -184,34 +218,25 @@ public abstract class ThreadedAnvilChunkStorage_scarpetChunkCreationMixin implem
 
         for (ChunkStatus status : ChunkStatus.createOrderedList())
         {
-            CarpetSettings.LOG.error("Creating layer: " + status.getId() + " for "+targetStatus.size()+" chunks");
+            report.put("layer_count_"+status.getId(),targetStatus.size());
+            long start = System.currentTimeMillis();
             if (status == ChunkStatus.LIGHT)
             {
-                //break;
                 serverLightingProvider.setTaskBatchSize(targetStatus.size() + 20);
             }
             for (ChunkPos chpos : new ArrayList<>(targetStatus.keySet()))
             {
                 if (targetStatus.get(chpos) == status)
                     targetStatus.remove(chpos);
-                //if (status==ChunkStatus.LIGHT)
-                //{
-                //    serverLightingProvider.tick();
-                //}
-                //CarpetSettings.LOG.error("Creating layer: " + status.getId());
                 world.getChunk(chpos.x, chpos.z, status);
                 if (status == ChunkStatus.FULL)
                     convertToFullChunk(currentChunkHolders.get(chpos.toLong()));
-                //CarpetSettings.LOG.error("    .. done");
-                //if (status==ChunkStatus.LIGHT)
-                //{
-                //    serverLightingProvider.tick();
-                //}
             }
             if (status == ChunkStatus.LIGHT)
-            {
+            { // default task batch size after initial generation is done
                 serverLightingProvider.setTaskBatchSize(5);
             }
+            report.put("layer_time_"+status.getId(), (int) (System.currentTimeMillis()-start));
         }
 
         mainThreadExecutor.runTasks(() -> mainThreadExecutor.getTaskCount() == 0);
@@ -222,5 +247,6 @@ public abstract class ThreadedAnvilChunkStorage_scarpetChunkCreationMixin implem
         {
             runnable.run();
         }
+        return report;
     }
 }

src/main/java/carpet/script/CarpetExpression.java

@@ -1249,14 +1249,24 @@ public class CarpetExpression
 
             ServerWorld world = cc.s.getWorld();
 
+            Value [] result = new Value[]{Value.NULL};
+
             ((CarpetContext)c).s.getMinecraftServer().submitAndJoin( () ->
             {
-                ((ThreadedAnvilChunkStorageInterface) world.getChunkManager().threadedAnvilChunkStorage).regenerateChunkRegion(requestedChunks);
+                Map<String, Integer> report = ((ThreadedAnvilChunkStorageInterface) world.getChunkManager().threadedAnvilChunkStorage).regenerateChunkRegion(requestedChunks);
                 for (ChunkPos chpos: requestedChunks)
+                {
                     if (world.getChunk(chpos.x, chpos.z, ChunkStatus.FULL, false) != null)
+                    {
                         this.forceChunkUpdate(chpos.getCenterBlockPos(), world);
+                    }
+                }
+                result[0] = MapValue.wrap(report.entrySet().stream().collect(Collectors.toMap(
+                        e -> new StringValue((String)((Map.Entry) e).getKey()),
+                        e ->  new NumericValue((Integer)((Map.Entry) e).getValue())
+                )));
             });
-            return LazyValue.NULL;
+            return (_c, _t) -> result[0];
         });
 
     }