SmoothLit joins the battle

- Not attached to the name
- Add SmoothLitVisual opt in interface, allowing any visuals to
  contribute light sections to the arena
- Remove lightChunks from VisualEmbedding, it has been usurped
- Pass total collected light sections from BEs, Es, and effects to the
  engine interface. It seemed the most proper way to hand off
  information from the impl to the backend
- Add SmoothLitVisualStorage to maintain the set of collected sections,
  though at the moment it is very naive and simply unions everything
  upon request, which is also naively done every frame

common/src/api/java/dev/engine_room/flywheel/api/backend/Engine.java

@@ -9,6 +9,7 @@ import dev.engine_room.flywheel.api.instance.Instance;
 import dev.engine_room.flywheel.api.task.Plan;
 import dev.engine_room.flywheel.api.task.TaskExecutor;
 import dev.engine_room.flywheel.api.visualization.VisualizationContext;
+import it.unimi.dsi.fastutil.longs.LongSet;
 import net.minecraft.client.Camera;
 import net.minecraft.core.BlockPos;
 import net.minecraft.core.Vec3i;
@@ -68,6 +69,13 @@ public interface Engine {
 	 */
 	void delete();
 
+	/**
+	 * Assign the set of sections that visuals have requested GPU light for.
+	 *
+	 * @param sections The set of sections.
+	 */
+	void lightSections(LongSet sections);
+
 	/**
 	 * A block to be rendered as a crumbling overlay.
 	 * @param progress The progress of the crumbling animation in the range [0, 10).

common/src/api/java/dev/engine_room/flywheel/api/visual/LitVisual.java

@@ -2,6 +2,8 @@ package dev.engine_room.flywheel.api.visual;
 
 import java.util.function.LongConsumer;
 
+import org.jetbrains.annotations.ApiStatus;
+
 import net.minecraft.core.SectionPos;
 
 /**
@@ -51,6 +53,7 @@ public interface LitVisual extends Visual {
 	 * A notifier object that can be used to indicate to the impl
 	 * that the sections a visual is contained in have changed.
 	 */
+	@ApiStatus.NonExtendable
 	interface Notifier {
 		/**
 		 * Invoke this to indicate to the impl that your visual has moved to a different set of sections.

common/src/api/java/dev/engine_room/flywheel/api/visual/SmoothLitVisual.java

@@ -0,0 +1,24 @@
+package dev.engine_room.flywheel.api.visual;
+
+import org.jetbrains.annotations.ApiStatus;
+
+import it.unimi.dsi.fastutil.longs.LongSet;
+
+public interface SmoothLitVisual extends Visual {
+	/**
+	 * Set the section property object.
+	 *
+	 * <p>This method is only called once, upon visual creation,
+	 *
+	 * @param property The property.
+	 */
+	void setSectionProperty(SectionProperty property);
+
+	@ApiStatus.NonExtendable
+	interface SectionProperty {
+		/**
+		 * Invoke this to indicate to the impl that your visual has moved to a different set of sections.
+		 */
+		void lightSections(LongSet sections);
+	}
+}

common/src/api/java/dev/engine_room/flywheel/api/visualization/VisualEmbedding.java

@@ -4,7 +4,6 @@ import org.joml.Matrix3fc;
 import org.joml.Matrix4fc;
 
 import dev.engine_room.flywheel.api.BackendImplemented;
-import it.unimi.dsi.fastutil.longs.LongSet;
 
 @BackendImplemented
 public interface VisualEmbedding extends VisualizationContext {
@@ -16,8 +15,6 @@ public interface VisualEmbedding extends VisualizationContext {
 	 */
 	void transforms(Matrix4fc pose, Matrix3fc normal);
 
-	void lightChunks(LongSet chunks);
-
 	/**
 	 * Delete this embedding.
 	 *

common/src/backend/java/dev/engine_room/flywheel/backend/engine/EngineImpl.java

@@ -22,6 +22,7 @@ import dev.engine_room.flywheel.backend.gl.GlStateTracker;
 import dev.engine_room.flywheel.lib.task.Flag;
 import dev.engine_room.flywheel.lib.task.NamedFlag;
 import dev.engine_room.flywheel.lib.task.SyncedPlan;
+import it.unimi.dsi.fastutil.longs.LongSet;
 import net.minecraft.client.Camera;
 import net.minecraft.core.BlockPos;
 import net.minecraft.core.Vec3i;
@@ -41,7 +42,7 @@ public class EngineImpl implements Engine {
 		this.drawManager = drawManager;
 		sqrMaxOriginDistance = maxOriginDistance * maxOriginDistance;
 		environmentStorage = new EnvironmentStorage();
-		lightStorage = new LightStorage(level, environmentStorage);
+		lightStorage = new LightStorage(level);
 	}
 
 	@Override
@@ -101,6 +102,11 @@ public class EngineImpl implements Engine {
 		lightStorage.delete();
 	}
 
+	@Override
+	public void lightSections(LongSet sections) {
+		lightStorage.sections(sections);
+	}
+
 	public <I extends Instance> Instancer<I> instancer(Environment environment, InstanceType<I> type, Model model, RenderStage stage) {
 		return drawManager.getInstancer(environment, type, model, stage);
 	}

common/src/backend/java/dev/engine_room/flywheel/backend/engine/EnvironmentStorage.java

@@ -1,8 +1,6 @@
 package dev.engine_room.flywheel.backend.engine;
 
 import dev.engine_room.flywheel.backend.engine.embed.AbstractEmbeddedEnvironment;
-import it.unimi.dsi.fastutil.longs.LongOpenHashSet;
-import it.unimi.dsi.fastutil.longs.LongSet;
 import it.unimi.dsi.fastutil.objects.ReferenceLinkedOpenHashSet;
 import it.unimi.dsi.fastutil.objects.ReferenceSet;
 import it.unimi.dsi.fastutil.objects.ReferenceSets;
@@ -18,10 +16,4 @@ public class EnvironmentStorage {
 		environments.removeIf(AbstractEmbeddedEnvironment::isDeleted);
 		environments.forEach(AbstractEmbeddedEnvironment::flush);
 	}
-
-	public LongSet allLightSections() {
-		var out = new LongOpenHashSet();
-		environments.forEach(e -> e.addLightSections(out));
-		return out;
-	}
 }

common/src/backend/java/dev/engine_room/flywheel/backend/engine/embed/AbstractEmbeddedEnvironment.java

@@ -15,7 +15,6 @@ import dev.engine_room.flywheel.api.visualization.VisualEmbedding;
 import dev.engine_room.flywheel.backend.compile.ContextShader;
 import dev.engine_room.flywheel.backend.engine.EngineImpl;
 import dev.engine_room.flywheel.backend.gl.shader.GlProgram;
-import it.unimi.dsi.fastutil.longs.LongSet;
 import net.minecraft.core.Vec3i;
 
 public abstract class AbstractEmbeddedEnvironment implements Environment, VisualEmbedding {
@@ -95,10 +94,6 @@ public abstract class AbstractEmbeddedEnvironment implements Environment, Visual
 		return deleted;
 	}
 
-	public void addLightSections(LongSet out) {
-
-	}
-
 	/**
 	 * Called by visuals
 	 */

common/src/backend/java/dev/engine_room/flywheel/backend/engine/embed/LightStorage.java

@@ -2,11 +2,11 @@ package dev.engine_room.flywheel.backend.engine.embed;
 
 import java.util.BitSet;
 
+import org.jetbrains.annotations.Nullable;
 import org.lwjgl.system.MemoryUtil;
 
 import dev.engine_room.flywheel.api.event.RenderContext;
 import dev.engine_room.flywheel.api.task.Plan;
-import dev.engine_room.flywheel.backend.engine.EnvironmentStorage;
 import dev.engine_room.flywheel.backend.engine.indirect.StagingBuffer;
 import dev.engine_room.flywheel.backend.gl.buffer.GlBuffer;
 import dev.engine_room.flywheel.lib.task.SimplePlan;
@@ -40,7 +40,6 @@ public class LightStorage {
 	private static final int INVALID_SECTION = -1;
 
 	private final LevelAccessor level;
-	private final EnvironmentStorage environmentStorage;
 
 	private final Arena arena;
 	private final Long2IntMap section2ArenaIndex = new Long2IntOpenHashMap();
@@ -51,18 +50,26 @@ public class LightStorage {
 	private final BitSet changed = new BitSet();
 	private boolean needsLutRebuild = false;
 
-	public LightStorage(LevelAccessor level, EnvironmentStorage environmentStorage) {
+	@Nullable
+	private LongSet requestedSections;
+
+	public LightStorage(LevelAccessor level) {
 		this.level = level;
-		this.environmentStorage = environmentStorage;
 
 		arena = new Arena(SECTION_SIZE_BYTES, DEFAULT_ARENA_CAPACITY_SECTIONS);
 	}
 
+	public void sections(LongSet sections) {
+		requestedSections = sections;
+	}
+
 	public Plan<RenderContext> createFramePlan() {
 		return SimplePlan.of(() -> {
-			var allLightSections = environmentStorage.allLightSections();
+			if (requestedSections == null) {
+				return;
+			}
 
-			removeUnusedSections(allLightSections);
+			removeUnusedSections(requestedSections);
 
 			var knownSections = section2ArenaIndex.keySet();
 
@@ -70,7 +77,7 @@ public class LightStorage {
 					.getUpdatedSections();
 
 			// Only add the new sections.
-			allLightSections.removeAll(knownSections);
+			requestedSections.removeAll(knownSections);
 
 			for (long updatedSection : updatedSections) {
 				for (int x = -1; x <= 1; x++) {
@@ -78,14 +85,14 @@ public class LightStorage {
 						for (int z = -1; z <= 1; z++) {
 							long section = SectionPos.offset(updatedSection, x, y, z);
 							if (knownSections.contains(section)) {
-								allLightSections.add(section);
+								requestedSections.add(section);
 							}
 						}
 					}
 				}
 			}
 
-			for (long section : allLightSections) {
+			for (long section : requestedSections) {
 				addSection(section);
 			}
 		});

common/src/backend/java/dev/engine_room/flywheel/backend/engine/embed/NestedEmbeddedEnvironment.java

@@ -5,7 +5,6 @@ import org.joml.Matrix4f;
 
 import dev.engine_room.flywheel.api.event.RenderStage;
 import dev.engine_room.flywheel.backend.engine.EngineImpl;
-import it.unimi.dsi.fastutil.longs.LongSet;
 
 public class NestedEmbeddedEnvironment extends AbstractEmbeddedEnvironment {
 	private final AbstractEmbeddedEnvironment parent;
@@ -15,11 +14,6 @@ public class NestedEmbeddedEnvironment extends AbstractEmbeddedEnvironment {
 		this.parent = parent;
 	}
 
-	@Override
-	public void lightChunks(LongSet chunks) {
-		// noop
-	}
-
 	@Override
 	public void composeMatrices(Matrix4f pose, Matrix3f normal) {
 		parent.composeMatrices(pose, normal);

common/src/backend/java/dev/engine_room/flywheel/backend/engine/embed/TopLevelEmbeddedEnvironment.java

@@ -5,27 +5,12 @@ import org.joml.Matrix4f;
 
 import dev.engine_room.flywheel.api.event.RenderStage;
 import dev.engine_room.flywheel.backend.engine.EngineImpl;
-import it.unimi.dsi.fastutil.longs.LongArraySet;
-import it.unimi.dsi.fastutil.longs.LongSet;
 
 public class TopLevelEmbeddedEnvironment extends AbstractEmbeddedEnvironment {
-	private final LongSet lightSections = new LongArraySet();
-
 	public TopLevelEmbeddedEnvironment(EngineImpl engine, RenderStage renderStage) {
 		super(engine, renderStage);
 	}
 
-	@Override
-	public void lightChunks(LongSet chunks) {
-		lightSections.clear();
-		lightSections.addAll(chunks);
-	}
-
-	@Override
-	public void addLightSections(LongSet out) {
-		out.addAll(lightSections);
-	}
-
 	@Override
 	public void composeMatrices(Matrix4f pose, Matrix3f normal) {
 		pose.set(this.pose);

common/src/main/java/dev/engine_room/flywheel/impl/visualization/VisualizationManagerImpl.java

@@ -45,6 +45,7 @@ import dev.engine_room.flywheel.lib.task.RaisePlan;
 import dev.engine_room.flywheel.lib.task.SimplePlan;
 import dev.engine_room.flywheel.lib.util.LevelAttached;
 import it.unimi.dsi.fastutil.longs.Long2ObjectMap;
+import it.unimi.dsi.fastutil.longs.LongOpenHashSet;
 import net.minecraft.client.Minecraft;
 import net.minecraft.core.Vec3i;
 import net.minecraft.server.level.BlockDestructionProgress;
@@ -104,6 +105,14 @@ public class VisualizationManagerImpl implements VisualizationManager {
 				.ifTrue(recreate)
 				.ifFalse(update)
 				.plan()
+				.then(SimplePlan.of(() -> {
+					// TODO: Lazily re-evaluate the union'd set
+					var out = new LongOpenHashSet();
+					out.addAll(blockEntities.lightSections());
+					out.addAll(entities.lightSections());
+					out.addAll(effects.lightSections());
+					engine.lightSections(out);
+				}))
 				.then(RaisePlan.raise(frameVisualsFlag))
 				.then(engine.createFramePlan())
 				.then(RaisePlan.raise(frameFlag));

common/src/main/java/dev/engine_room/flywheel/impl/visualization/manager/VisualManagerImpl.java

@@ -10,6 +10,7 @@ import dev.engine_room.flywheel.api.visualization.VisualManager;
 import dev.engine_room.flywheel.impl.visualization.storage.Storage;
 import dev.engine_room.flywheel.impl.visualization.storage.Transaction;
 import dev.engine_room.flywheel.lib.task.SimplePlan;
+import it.unimi.dsi.fastutil.longs.LongSet;
 
 public class VisualManagerImpl<T, S extends Storage<T>> implements VisualManager<T> {
 	private final Queue<Transaction<T>> queue = new ConcurrentLinkedQueue<>();
@@ -74,4 +75,8 @@ public class VisualManagerImpl<T, S extends Storage<T>> implements VisualManager
 		return SimplePlan.<TickableVisual.Context>of(context -> processQueue(1))
 				.then(storage.tickPlan());
 	}
+
+	public LongSet lightSections() {
+		return getStorage().lightSections();
+	}
 }

common/src/main/java/dev/engine_room/flywheel/impl/visualization/storage/SmoothLitVisualStorage.java

@@ -0,0 +1,45 @@
+package dev.engine_room.flywheel.impl.visualization.storage;
+
+import java.util.Map;
+
+import dev.engine_room.flywheel.api.visual.SmoothLitVisual;
+import it.unimi.dsi.fastutil.longs.LongArraySet;
+import it.unimi.dsi.fastutil.longs.LongOpenHashSet;
+import it.unimi.dsi.fastutil.longs.LongSet;
+import it.unimi.dsi.fastutil.objects.Reference2ObjectOpenHashMap;
+
+public class SmoothLitVisualStorage {
+	private final Map<SmoothLitVisual, SectionProperty> visuals = new Reference2ObjectOpenHashMap<>();
+
+	public LongSet sections() {
+		var out = new LongOpenHashSet();
+		for (SectionProperty value : visuals.values()) {
+			out.addAll(value.sections);
+		}
+		return out;
+	}
+
+	public void remove(SmoothLitVisual smoothLit) {
+		visuals.remove(smoothLit);
+	}
+
+	public void add(SmoothLitVisual smoothLit) {
+		var sections = new SectionProperty();
+		visuals.put(smoothLit, sections);
+		smoothLit.setSectionProperty(sections);
+	}
+
+	public void clear() {
+		visuals.clear();
+	}
+
+	private static final class SectionProperty implements SmoothLitVisual.SectionProperty {
+		private final LongSet sections = new LongArraySet();
+
+		@Override
+		public void lightSections(LongSet sections) {
+			this.sections.clear();
+			this.sections.addAll(sections);
+		}
+	}
+}

common/src/main/java/dev/engine_room/flywheel/impl/visualization/storage/Storage.java

@@ -11,6 +11,7 @@ import org.jetbrains.annotations.Nullable;
 import dev.engine_room.flywheel.api.task.Plan;
 import dev.engine_room.flywheel.api.visual.DynamicVisual;
 import dev.engine_room.flywheel.api.visual.LitVisual;
+import dev.engine_room.flywheel.api.visual.SmoothLitVisual;
 import dev.engine_room.flywheel.api.visual.TickableVisual;
 import dev.engine_room.flywheel.api.visual.Visual;
 import dev.engine_room.flywheel.api.visualization.VisualizationContext;
@@ -19,6 +20,7 @@ import dev.engine_room.flywheel.lib.task.NestedPlan;
 import dev.engine_room.flywheel.lib.task.PlanMap;
 import dev.engine_room.flywheel.lib.visual.SimpleDynamicVisual;
 import dev.engine_room.flywheel.lib.visual.SimpleTickableVisual;
+import it.unimi.dsi.fastutil.longs.LongSet;
 import it.unimi.dsi.fastutil.objects.Reference2ObjectOpenHashMap;
 
 public abstract class Storage<T> {
@@ -28,6 +30,7 @@ public abstract class Storage<T> {
 	protected final List<SimpleDynamicVisual> simpleDynamicVisuals = new ArrayList<>();
 	protected final List<SimpleTickableVisual> simpleTickableVisuals = new ArrayList<>();
 	protected final LitVisualStorage litVisuals = new LitVisualStorage();
+	protected final SmoothLitVisualStorage smoothLitVisuals = new SmoothLitVisualStorage();
 
 	private final Map<T, Visual> visuals = new Reference2ObjectOpenHashMap<>();
 
@@ -71,6 +74,9 @@ public abstract class Storage<T> {
 		if (visual instanceof LitVisual lit) {
 			litVisuals.remove(lit);
 		}
+		if (visual instanceof SmoothLitVisual smoothLit) {
+			smoothLitVisuals.remove(smoothLit);
+		}
 		visual.delete();
 	}
 
@@ -90,6 +96,7 @@ public abstract class Storage<T> {
 		simpleTickableVisuals.clear();
 		simpleDynamicVisuals.clear();
 		litVisuals.clear();
+		smoothLitVisuals.clear();
 		visuals.replaceAll((obj, visual) -> {
 			visual.delete();
 
@@ -156,6 +163,10 @@ public abstract class Storage<T> {
 		if (visual instanceof LitVisual lit) {
 			litVisuals.setNotifierAndAdd(lit);
 		}
+
+		if (visual instanceof SmoothLitVisual smoothLit) {
+			smoothLitVisuals.add(smoothLit);
+		}
 	}
 
 	/**
@@ -164,4 +175,8 @@ public abstract class Storage<T> {
 	 * @return true if the object is currently capable of being visualized.
 	 */
 	public abstract boolean willAccept(T obj);
+
+	public LongSet lightSections() {
+		return smoothLitVisuals.sections();
+	}
 }