support the cubic chunks async terrain gen api and periodically unloa…

…d generated cubes

src/main/java/net/daporkchop/fp2/compat/cc/asyncblockaccess/CCAsyncBlockAccessImpl.java

@@ -26,6 +26,7 @@
 import io.github.opencubicchunks.cubicchunks.api.world.ICubeProviderServer;
 import io.github.opencubicchunks.cubicchunks.api.world.ICubicWorldServer;
 import io.github.opencubicchunks.cubicchunks.api.world.storage.ICubicStorage;
+import io.github.opencubicchunks.cubicchunks.api.worldgen.ICubeGenerator;
 import io.github.opencubicchunks.cubicchunks.core.asm.mixin.ICubicWorldInternal;
 import io.github.opencubicchunks.cubicchunks.core.server.chunkio.AsyncBatchingCubeIO;
 import io.github.opencubicchunks.cubicchunks.core.server.chunkio.ICubeIO;
@@ -38,6 +39,7 @@
 import net.daporkchop.fp2.compat.cc.cube.CubeWithoutWorld;
 import net.daporkchop.fp2.compat.vanilla.IBiomeAccess;
 import net.daporkchop.fp2.compat.vanilla.IBlockHeightAccess;
+import net.daporkchop.fp2.mode.api.ctx.IFarWorldServer;
 import net.daporkchop.fp2.server.worldlistener.IWorldChangeListener;
 import net.daporkchop.fp2.server.worldlistener.WorldChangeListenerManager;
 import net.daporkchop.fp2.util.datastructure.Datastructures;
@@ -61,11 +63,13 @@
 import net.minecraft.world.WorldType;
 import net.minecraft.world.biome.Biome;
 import net.minecraft.world.chunk.Chunk;
+import net.minecraft.world.chunk.IChunkProvider;
 import net.minecraft.world.chunk.storage.ExtendedBlockStorage;
 
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.concurrent.atomic.AtomicInteger;
 import java.util.function.Function;
 import java.util.stream.Stream;
 
@@ -82,6 +86,7 @@ public class CCAsyncBlockAccessImpl implements IAsyncBlockAccess, IWorldChangeLi
     protected final WorldServer world;
     protected final ICubeIO io;
     protected final ICubicStorage storage;
+    protected final ICubeGenerator generator;
 
     protected final ColumnCache columns = new ColumnCache();
     protected final CubeCache cubes = new CubeCache();
@@ -91,10 +96,13 @@ public class CCAsyncBlockAccessImpl implements IAsyncBlockAccess, IWorldChangeLi
     protected final NDimensionalIntSegtreeSet columnsExistCache;
     protected final NDimensionalIntSegtreeSet cubesExistCache;
 
+    protected final AtomicInteger generatedCount = new AtomicInteger();
+
     public CCAsyncBlockAccessImpl(@NonNull WorldServer world) {
         this.world = world;
         this.io = ((ICubeProviderInternal.Server) ((ICubicWorldInternal) world).getCubeCache()).getCubeIO();
         this.storage = PUnsafe.getObject(AsyncBatchingCubeIO.class.cast(this.io), ASYNCBATCHINGCUBEIO_STORAGE_OFFSET);
+        this.generator = ((ICubicWorldServer) world).getCubeGenerator();
 
         this.emptyStorage = new ExtendedBlockStorage(0, world.provider.hasSkyLight());
 
@@ -175,6 +183,18 @@ public void onCubeSaved(@NonNull World world, int cubeX, int cubeY, int cubeZ, @
         this.cubes.notifyUpdate(new CubePos(cubeX, cubeY, cubeZ), nbt);
     }
 
+    @Override
+    public void onTickEnd() {
+        //if 8192 things have been generated, run a full chunk gc!
+        //  if we don't do this, the gc will only be triggered when a player has been moving for more than some number of ticks. the player might just be standing still
+        //  while waiting for terrain to load in, so we need to do this to prevent a memory leak.
+        if (this.generatedCount.get() >= 8192) {
+            this.generatedCount.lazySet(0);
+
+            ((ICubicWorldServer) this.world).unloadOldCubes();
+        }
+    }
+
     @Override
     public boolean anyColumnIntersects(int tileX, int tileZ, int level) {
         return this.columnsExistCache.containsAny(level, tileX, tileZ);
@@ -262,12 +282,18 @@ protected IColumn loadFromDisk(@NonNull ChunkPos key, @NonNull Object param) {
 
         @Override
         protected void triggerGeneration(@NonNull ChunkPos key, @NonNull Object param) {
+            //spin until the generator reports that it's ready
+            while (CCAsyncBlockAccessImpl.this.generator.pollAsyncColumnGenerator(key.x, key.z) != ICubeGenerator.GeneratorReadyState.READY) {
+                PorkUtil.sleep(1L);
+            }
+
             //load and immediately save column on server thread
             ThreadingHelper.scheduleTaskInWorldThread(CCAsyncBlockAccessImpl.this.world, () -> {
                 Chunk column = ((ICubicWorldServer) CCAsyncBlockAccessImpl.this.world)
                         .getCubeCache().getColumn(key.x, key.z, ICubeProviderServer.Requirement.POPULATE);
                 if (column != null && !column.isEmpty()) {
                     CCAsyncBlockAccessImpl.this.io.saveColumn(column);
+                    CCAsyncBlockAccessImpl.this.generatedCount.incrementAndGet();
                 }
             }).join();
         }
@@ -302,12 +328,19 @@ protected ICube loadFromDisk(@NonNull CubePos key, @NonNull Chunk param) {
 
         @Override
         protected void triggerGeneration(@NonNull CubePos key, @NonNull Chunk param) {
+            //spin until the generator reports that it's ready
+            while (CCAsyncBlockAccessImpl.this.generator.pollAsyncCubeGenerator(key.getX(), key.getY(), key.getZ()) != ICubeGenerator.GeneratorReadyState.READY
+                   || CCAsyncBlockAccessImpl.this.generator.pollAsyncCubePopulator(key.getX(), key.getY(), key.getZ()) != ICubeGenerator.GeneratorReadyState.READY) {
+                PorkUtil.sleep(1L);
+            }
+
             ThreadingHelper.scheduleTaskInWorldThread(CCAsyncBlockAccessImpl.this.world, () -> {
                 //TODO: save column as well if needed
                 ICube cube = ((ICubicWorldServer) CCAsyncBlockAccessImpl.this.world)
                         .getCubeCache().getCube(key.getX(), key.getY(), key.getZ(), ICubeProviderServer.Requirement.LIGHT);
                 if (cube != null && cube.isInitialLightingDone()) {
                     CCAsyncBlockAccessImpl.this.io.saveCube((Cube) cube);
+                    CCAsyncBlockAccessImpl.this.generatedCount.incrementAndGet();
                 }
             }).join();
         }