The hardest problem

- Rename most InstancePager terminology
- Rename MODEL_INDEX buffer stuffs

common/src/backend/java/dev/engine_room/flywheel/backend/engine/indirect/BufferBindings.java

@@ -3,7 +3,7 @@
 public final class BufferBindings {
 	public static final int INSTANCE = 0;
 	public static final int TARGET = 1;
-	public static final int MODEL_INDEX = 2;
+	public static final int PAGE_FRAME_DESCRIPTOR = 2;
 	public static final int MODEL = 3;
 	public static final int DRAW = 4;
 	public static final int LIGHT_LUT = 5;

common/src/backend/java/dev/engine_room/flywheel/backend/engine/indirect/IndirectBuffers.java

@@ -32,14 +32,14 @@ public class IndirectBuffers {
 	// Offsets to the vbos
 	private static final long INSTANCE_HANDLE_OFFSET = HANDLE_OFFSET;
 	private static final long TARGET_HANDLE_OFFSET = INT_SIZE;
-	private static final long MODEL_INDEX_HANDLE_OFFSET = INT_SIZE * 2;
+	private static final long PAGE_FRAME_DESCRIPTOR_HANDLE_OFFSET = INT_SIZE * 2;
 	private static final long MODEL_HANDLE_OFFSET = INT_SIZE * 3;
 	private static final long DRAW_HANDLE_OFFSET = INT_SIZE * 4;
 
 	// Offsets to the sizes
 	private static final long INSTANCE_SIZE_OFFSET = SIZE_OFFSET;
 	private static final long TARGET_SIZE_OFFSET = SIZE_OFFSET + PTR_SIZE;
-	private static final long MODEL_INDEX_SIZE_OFFSET = SIZE_OFFSET + PTR_SIZE * 2;
+	private static final long PAGE_FRAME_DESCRIPTOR_SIZE_OFFSET = SIZE_OFFSET + PTR_SIZE * 2;
 	private static final long MODEL_SIZE_OFFSET = SIZE_OFFSET + PTR_SIZE * 3;
 	private static final long DRAW_SIZE_OFFSET = SIZE_OFFSET + PTR_SIZE * 4;
 
@@ -62,7 +62,7 @@ public class IndirectBuffers {
 	private final MemoryBlock multiBindBlock;
 	private final long instanceStride;
 
-	public final InstancePager pageFile;
+	public final ObjectStorage objectStorage;
 	public final ResizableStorageArray target;
 	public final ResizableStorageArray model;
 	public final ResizableStorageArray draw;
@@ -71,7 +71,7 @@ public class IndirectBuffers {
 		this.instanceStride = instanceStride;
 		this.multiBindBlock = MemoryBlock.calloc(BUFFERS_SIZE_BYTES, 1);
 
-		pageFile = new InstancePager(instanceStride);
+		objectStorage = new ObjectStorage(instanceStride);
 		target = new ResizableStorageArray(INT_SIZE, INSTANCE_GROWTH_FACTOR);
 		model = new ResizableStorageArray(MODEL_STRIDE, MODEL_GROWTH_FACTOR);
 		draw = new ResizableStorageArray(DRAW_COMMAND_STRIDE, DRAW_GROWTH_FACTOR);
@@ -83,15 +83,15 @@ void updateCounts(int instanceCount, int modelCount, int drawCount) {
 		draw.ensureCapacity(drawCount);
 
 		final long ptr = multiBindBlock.ptr();
-		MemoryUtil.memPutInt(ptr + INSTANCE_HANDLE_OFFSET, pageFile.objects.handle());
+		MemoryUtil.memPutInt(ptr + INSTANCE_HANDLE_OFFSET, objectStorage.objectBuffer.handle());
 		MemoryUtil.memPutInt(ptr + TARGET_HANDLE_OFFSET, target.handle());
-		MemoryUtil.memPutInt(ptr + MODEL_INDEX_HANDLE_OFFSET, pageFile.pageTable.handle());
+		MemoryUtil.memPutInt(ptr + PAGE_FRAME_DESCRIPTOR_HANDLE_OFFSET, objectStorage.frameDescriptorBuffer.handle());
 		MemoryUtil.memPutInt(ptr + MODEL_HANDLE_OFFSET, model.handle());
 		MemoryUtil.memPutInt(ptr + DRAW_HANDLE_OFFSET, draw.handle());
 
-		MemoryUtil.memPutAddress(ptr + INSTANCE_SIZE_OFFSET, pageFile.objects.capacity());
+		MemoryUtil.memPutAddress(ptr + INSTANCE_SIZE_OFFSET, objectStorage.objectBuffer.capacity());
 		MemoryUtil.memPutAddress(ptr + TARGET_SIZE_OFFSET, INT_SIZE * instanceCount);
-		MemoryUtil.memPutAddress(ptr + MODEL_INDEX_SIZE_OFFSET, pageFile.pageTable.capacity());
+		MemoryUtil.memPutAddress(ptr + PAGE_FRAME_DESCRIPTOR_SIZE_OFFSET, objectStorage.frameDescriptorBuffer.capacity());
 		MemoryUtil.memPutAddress(ptr + MODEL_SIZE_OFFSET, MODEL_STRIDE * modelCount);
 		MemoryUtil.memPutAddress(ptr + DRAW_SIZE_OFFSET, DRAW_COMMAND_STRIDE * drawCount);
 	}
@@ -121,7 +121,7 @@ public void bindForCrumbling() {
 	public void delete() {
 		multiBindBlock.free();
 
-		pageFile.delete();
+		objectStorage.delete();
 		target.delete();
 		model.delete();
 		draw.delete();

common/src/backend/java/dev/engine_room/flywheel/backend/engine/indirect/IndirectCullingGroup.java

@@ -95,7 +95,7 @@ public void upload(StagingBuffer stagingBuffer) {
 		// Upload only instances that have changed.
 		uploadInstances(stagingBuffer);
 
-		buffers.pageFile.uploadTable(stagingBuffer);
+		buffers.objectStorage.uploadDescriptors(stagingBuffer);
 
 		// We need to upload the models every frame to reset the instance count.
 		uploadModels(stagingBuffer);
@@ -119,7 +119,7 @@ public void dispatchCull() {
 		cullProgram.bind();
 
 		buffers.bindForCompute();
-		glDispatchCompute(buffers.pageFile.capacity(), 1, 1);
+		glDispatchCompute(buffers.objectStorage.capacity(), 1, 1);
 	}
 
 	public void dispatchApply() {
@@ -172,7 +172,7 @@ public boolean hasVisualType(VisualType visualType) {
 	}
 
 	public void add(IndirectInstancer<I> instancer, InstancerKey<I> key, MeshPool meshPool) {
-		instancer.pageFile = buffers.pageFile.createAllocation();
+		instancer.mapping = buffers.objectStorage.createMapping();
 		instancer.postUpdate(instancers.size(), -1);
 
 		instancers.add(instancer);
@@ -245,7 +245,7 @@ private void drawBarrier() {
 
 	private void uploadInstances(StagingBuffer stagingBuffer) {
 		for (var instancer : instancers) {
-			instancer.uploadInstances(stagingBuffer, buffers.pageFile.objects.handle());
+			instancer.uploadInstances(stagingBuffer, buffers.objectStorage.objectBuffer.handle());
 		}
 	}
 

common/src/backend/java/dev/engine_room/flywheel/backend/engine/indirect/IndirectInstancer.java

@@ -3,6 +3,7 @@
 import java.util.ArrayList;
 import java.util.List;
 
+import org.jetbrains.annotations.UnknownNullability;
 import org.joml.Vector4fc;
 import org.lwjgl.system.MemoryUtil;
 
@@ -23,7 +24,7 @@ public class IndirectInstancer<I extends Instance> extends AbstractInstancer<I>
 
 	private final AtomicBitSet changedPages = new AtomicBitSet();
 
-	public InstancePager.Allocation pageFile;
+	public ObjectStorage.@UnknownNullability Mapping mapping;
 
 	private int modelIndex = -1;
 	private int baseInstance = -1;
@@ -42,14 +43,14 @@ public void notifyDirty(int index) {
 			return;
 		}
 		changed.set(index);
-		changedPages.set(InstancePager.object2Page(index));
+		changedPages.set(ObjectStorage.objectIndex2PageIndex(index));
 	}
 
 	@Override
 	protected void setRangeChanged(int start, int end) {
 		super.setRangeChanged(start, end);
 
-		changedPages.set(InstancePager.object2Page(start), InstancePager.object2Page(end) + 1);
+		changedPages.set(ObjectStorage.objectIndex2PageIndex(start), ObjectStorage.objectIndex2PageIndex(end) + 1);
 	}
 
 	public void addDraw(IndirectDraw draw) {
@@ -67,7 +68,7 @@ public void update() {
 	public void postUpdate(int modelIndex, int baseInstance) {
 		this.modelIndex = modelIndex;
 		this.baseInstance = baseInstance;
-		pageFile.update(modelIndex, instanceCount());
+		mapping.update(modelIndex, instanceCount());
 	}
 
 	public void writeModel(long ptr) {
@@ -81,20 +82,20 @@ public void writeModel(long ptr) {
 	}
 
 	public void uploadInstances(StagingBuffer stagingBuffer, int instanceVbo) {
-		int numPages = pageFile.pageCount();
+		int numPages = mapping.pageCount();
 
 		var instanceCount = instances.size();
 
 		for (int page = changedPages.nextSetBit(0); page >= 0 && page < numPages; page = changedPages.nextSetBit(page + 1)) {
-			int startObject = InstancePager.page2Object(page);
+			int startObject = ObjectStorage.pageIndex2ObjectIndex(page);
 
 			if (startObject >= instanceCount) {
 				break;
 			}
 
-			int endObject = Math.min(instanceCount, InstancePager.page2Object(page + 1));
+			int endObject = Math.min(instanceCount, ObjectStorage.pageIndex2ObjectIndex(page + 1));
 
-			long baseByte = pageFile.page2ByteOffset(page);
+			long baseByte = mapping.page2ByteOffset(page);
 			long size = (endObject - startObject) * instanceStride;
 
 			stagingBuffer.enqueueCopy(size, instanceVbo, baseByte, ptr -> {
@@ -115,7 +116,7 @@ public void delete() {
 			draw.delete();
 		}
 
-		pageFile.delete();
+		mapping.delete();
 	}
 
 	public int modelIndex() {