Allow batch reading of mesh chunks

CHANGELOG.unreleased.md

@@ -14,6 +14,7 @@ For upgrade instructions, please check the [migration guide](MIGRATIONS.released
 - In addition to drag and drop, the selected tree(s) in the Skeleton tab can also be moved into another group by right-clicking the target group and selecting "Move selected tree(s) here". [#7005](https://github.com/scalableminds/webknossos/pull/7005)
 
 ### Changed
+- Loading of precomputed meshes got significantly faster (especially when using a mesh file for an oversegmentation with an applied agglomerate mapping). [#7001](https://github.com/scalableminds/webknossos/pull/7001)
 
 ### Fixed
 - Fixed that changing a segment color could lead to a crash. [#7000](https://github.com/scalableminds/webknossos/pull/7000)

frontend/javascripts/admin/api/mesh_v3.ts

@@ -1,4 +1,5 @@
 import Request from "libs/request";
+import _ from "lodash";
 import { Vector3, Vector4 } from "oxalis/constants";
 import { APIDatasetId } from "types/api_flow_types";
 import { doWithToken } from "./token";
@@ -62,26 +63,50 @@ export function getMeshfileChunksForSegment(
   });
 }
 
+type MeshChunkDataRequestV3 = {
+  byteOffset: number;
+  byteSize: number;
+};
+
+type MeshChunkDataRequestV3List = {
+  meshFile: String;
+  requests: MeshChunkDataRequestV3[];
+};
+
 export function getMeshfileChunkData(
   dataStoreUrl: string,
   datasetId: APIDatasetId,
   layerName: string,
-  meshFile: string,
-  byteOffset: number,
-  byteSize: number,
-): Promise<ArrayBuffer> {
+  batchDescription: MeshChunkDataRequestV3List,
+): Promise<ArrayBuffer[]> {
   return doWithToken(async (token) => {
-    const data = await Request.sendJSONReceiveArraybufferWithHeaders(
+    const dracoDataChunks = await Request.sendJSONReceiveArraybuffer(
       `${dataStoreUrl}/data/datasets/${datasetId.owningOrganization}/${datasetId.name}/layers/${layerName}/meshes/formatVersion/3/chunks/data?token=${token}`,
       {
-        data: {
-          meshFile,
-          byteOffset,
-          byteSize,
-        },
-        useWebworkerForArrayBuffer: false,
+        data: batchDescription,
+        useWebworkerForArrayBuffer: true,
       },
     );
-    return data;
+    const chunkCount = batchDescription.requests.length;
+    const jumpPositionsForChunks = [];
+    let cumsum = 0;
+    for (const req of batchDescription.requests) {
+      jumpPositionsForChunks.push(cumsum);
+      cumsum += req.byteSize;
+    }
+    jumpPositionsForChunks.push(cumsum);
+
+    const dataEntries = [];
+    for (let chunkIdx = 0; chunkIdx < chunkCount; chunkIdx++) {
+      // slice() creates a copy of the data, but working with TypedArray Views would cause
+      // issues when transferring the data to a webworker.
+      const dracoData = dracoDataChunks.slice(
+        jumpPositionsForChunks[chunkIdx],
+        jumpPositionsForChunks[chunkIdx + 1],
+      );
+      dataEntries.push(dracoData);
+    }
+
+    return dataEntries;
   });
 }

frontend/javascripts/libs/DRACOLoader.ts

@@ -1,7 +1,15 @@
 // @ts-nocheck
 /* eslint-disable */
-// Copied from node_modules/three/examples/jsm/loaders/DRACOLoader.js to fix ERR_REQUIRE_ESM error.
-import { BufferAttribute, BufferGeometry, FileLoader, Loader } from "three";
+// Copied from https://github.com/mrdoob/three.js/pull/25475 / DRACOLoader.js to fix ERR_REQUIRE_ESM error.
+import {
+  BufferAttribute,
+  BufferGeometry,
+  Color,
+  FileLoader,
+  Loader,
+  LinearSRGBColorSpace,
+  SRGBColorSpace,
+} from "three";
 
 const _taskCache = new WeakMap();
 
@@ -62,44 +70,35 @@ class DRACOLoader extends Loader {
     loader.load(
       url,
       (buffer) => {
-        const taskConfig = {
-          attributeIDs: this.defaultAttributeIDs,
-          attributeTypes: this.defaultAttributeTypes,
-          useUniqueIDs: false,
-        };
-
-        this.decodeGeometry(buffer, taskConfig).then(onLoad).catch(onError);
+        this.parse(buffer, onLoad, onError);
       },
       onProgress,
       onError,
     );
   }
 
-  /** @deprecated Kept for backward-compatibility with previous DRACOLoader versions. */
-  decodeDracoFile(buffer, callback, attributeIDs, attributeTypes) {
+  parse(buffer, onLoad, onError) {
+    this.decodeDracoFile(buffer, onLoad, null, null, SRGBColorSpace).catch(onError);
+  }
+
+  decodeDracoFile(
+    buffer,
+    callback,
+    attributeIDs,
+    attributeTypes,
+    vertexColorSpace = LinearSRGBColorSpace,
+  ) {
     const taskConfig = {
       attributeIDs: attributeIDs || this.defaultAttributeIDs,
       attributeTypes: attributeTypes || this.defaultAttributeTypes,
       useUniqueIDs: !!attributeIDs,
+      vertexColorSpace: vertexColorSpace,
     };
 
-    this.decodeGeometry(buffer, taskConfig).then(callback);
+    return this.decodeGeometry(buffer, taskConfig).then(callback);
   }
 
   decodeGeometry(buffer, taskConfig) {
-    // TODO: For backward-compatibility, support 'attributeTypes' objects containing
-    // references (rather than names) to typed array constructors. These must be
-    // serialized before sending them to the worker.
-    for (const attribute in taskConfig.attributeTypes) {
-      const type = taskConfig.attributeTypes[attribute];
-
-      if (type.BYTES_PER_ELEMENT !== undefined) {
-        taskConfig.attributeTypes[attribute] = type.name;
-      }
-    }
-
-    //
-
     const taskKey = JSON.stringify(taskConfig);
 
     // Check for an existing task using this buffer. A transferred buffer cannot be transferred
@@ -172,17 +171,39 @@ class DRACOLoader extends Loader {
     }
 
     for (let i = 0; i < geometryData.attributes.length; i++) {
-      const attribute = geometryData.attributes[i];
-      const name = attribute.name;
-      const array = attribute.array;
-      const itemSize = attribute.itemSize;
+      const result = geometryData.attributes[i];
+      const name = result.name;
+      const array = result.array;
+      const itemSize = result.itemSize;
+
+      const attribute = new BufferAttribute(array, itemSize);
+
+      if (name === "color") {
+        this._assignVertexColorSpace(attribute, result.vertexColorSpace);
+      }
 
-      geometry.setAttribute(name, new BufferAttribute(array, itemSize));
+      geometry.setAttribute(name, attribute);
     }
 
     return geometry;
   }
 
+  _assignVertexColorSpace(attribute, inputColorSpace) {
+    // While .drc files do not specify colorspace, the only 'official' tooling
+    // is PLY and OBJ converters, which use sRGB. We'll assume sRGB when a .drc
+    // file is passed into .load() or .parse(). GLTFLoader uses internal APIs
+    // to decode geometry, and vertex colors are already Linear-sRGB in there.
+
+    if (inputColorSpace !== SRGBColorSpace) return;
+
+    const _color = new Color();
+
+    for (let i = 0, il = attribute.count; i < il; i++) {
+      _color.fromBufferAttribute(attribute, i).convertSRGBToLinear();
+      attribute.setXYZ(i, _color.r, _color.g, _color.b);
+    }
+  }
+
   _loadLibrary(url, responseType) {
     const loader = new FileLoader(this.manager);
     loader.setPath(this.decoderPath);
@@ -298,6 +319,10 @@ class DRACOLoader extends Loader {
 
     this.workerPool.length = 0;
 
+    if (this.workerSourceURL !== "") {
+      URL.revokeObjectURL(this.workerSourceURL);
+    }
+
     return this;
   }
 }
@@ -320,7 +345,7 @@ function DRACOWorker() {
             resolve({ draco: draco });
           };
 
-          DracoDecoderModule(decoderConfig);
+          DracoDecoderModule(decoderConfig); // eslint-disable-line no-undef
         });
         break;
 
@@ -330,11 +355,9 @@ function DRACOWorker() {
         decoderPending.then((module) => {
           const draco = module.draco;
           const decoder = new draco.Decoder();
-          const decoderBuffer = new draco.DecoderBuffer();
-          decoderBuffer.Init(new Int8Array(buffer), buffer.byteLength);
 
           try {
-            const geometry = decodeGeometry(draco, decoder, decoderBuffer, taskConfig);
+            const geometry = decodeGeometry(draco, decoder, new Int8Array(buffer), taskConfig);
 
             const buffers = geometry.attributes.map((attr) => attr.array.buffer);
 
@@ -346,29 +369,27 @@ function DRACOWorker() {
 
             self.postMessage({ type: "error", id: message.id, error: error.message });
           } finally {
-            draco.destroy(decoderBuffer);
             draco.destroy(decoder);
           }
         });
         break;
     }
   };
 
-  function decodeGeometry(draco, decoder, decoderBuffer, taskConfig) {
+  function decodeGeometry(draco, decoder, array, taskConfig) {
     const attributeIDs = taskConfig.attributeIDs;
     const attributeTypes = taskConfig.attributeTypes;
 
     let dracoGeometry;
     let decodingStatus;
-
-    const geometryType = decoder.GetEncodedGeometryType(decoderBuffer);
+    const geometryType = decoder.GetEncodedGeometryType(array);
 
     if (geometryType === draco.TRIANGULAR_MESH) {
       dracoGeometry = new draco.Mesh();
-      decodingStatus = decoder.DecodeBufferToMesh(decoderBuffer, dracoGeometry);
+      decodingStatus = decoder.DecodeArrayToMesh(array, array.byteLength, dracoGeometry);
     } else if (geometryType === draco.POINT_CLOUD) {
       dracoGeometry = new draco.PointCloud();
-      decodingStatus = decoder.DecodeBufferToPointCloud(decoderBuffer, dracoGeometry);
+      decodingStatus = decoder.DecodeArrayToPointCloud(array, array.byteLength, dracoGeometry);
     } else {
       throw new Error("THREE.DRACOLoader: Unexpected geometry type.");
     }
@@ -401,9 +422,20 @@ function DRACOWorker() {
         attribute = decoder.GetAttribute(dracoGeometry, attributeID);
       }
 
-      geometry.attributes.push(
-        decodeAttribute(draco, decoder, dracoGeometry, attributeName, attributeType, attribute),
+      const attributeResult = decodeAttribute(
+        draco,
+        decoder,
+        dracoGeometry,
+        attributeName,
+        attributeType,
+        attribute,
       );
+
+      if (attributeName === "color") {
+        attributeResult.vertexColorSpace = taskConfig.vertexColorSpace;
+      }
+
+      geometry.attributes.push(attributeResult);
     }
 
     // Add index.

frontend/javascripts/libs/draco.ts

@@ -5,13 +5,13 @@ let _dracoLoader: CustomDRACOLoader | null;
 
 class CustomDRACOLoader extends DRACOLoader {
   // Subclass to create a promise-based API and add typing
-  decodeDracoFileAsync = (buffer: ArrayBuffer, ...args: any[]): Promise<BufferGeometry> =>
-    new Promise((resolve) => {
+  decodeDracoFileAsync = (buffer: ArrayBuffer): Promise<BufferGeometry> =>
+    new Promise((resolve, reject) => {
       if (_dracoLoader == null) {
         throw new Error("DracoLoader not instantiated.");
       }
       // @ts-ignore
-      _dracoLoader.decodeDracoFile(buffer, resolve, ...args);
+      _dracoLoader.parse(buffer, resolve, reject);
     });
 }
 

frontend/javascripts/libs/task_pool.ts

@@ -1,5 +1,6 @@
 import type { Saga, Task } from "oxalis/model/sagas/effect-generators";
 import { join, call, fork } from "typed-redux-saga";
+
 /*
   Given an array of async tasks, processTaskWithPool
   allows to execute at most ${poolSize} tasks concurrently.
@@ -11,8 +12,7 @@ export default function* processTaskWithPool(
 ): Saga<void> {
   const startedTasks: Array<Task<void>> = [];
   let isFinalResolveScheduled = false;
-  // @ts-expect-error ts-migrate(7034) FIXME: Variable 'error' implicitly has type 'any' in some... Remove this comment to see the full error message
-  let error = null;
+  let error: Error | null = null;
 
   // @ts-expect-error ts-migrate(7006) FIXME: Parameter 'fn' implicitly has an 'any' type.
   function* forkSafely(fn): Saga<void> {
@@ -22,7 +22,7 @@ export default function* processTaskWithPool(
     try {
       yield* call(fn);
     } catch (e) {
-      error = e;
+      error = e as Error;
     }
   }
 
@@ -34,7 +34,6 @@ export default function* processTaskWithPool(
         // awaited now together.
         // @ts-expect-error ts-migrate(2769) FIXME: No overload matches this call.
         yield* join(startedTasks);
-        // @ts-expect-error ts-migrate(7005) FIXME: Variable 'error' implicitly has an 'any' type.
         if (error != null) throw error;
       }
 
@@ -53,6 +52,7 @@ export default function* processTaskWithPool(
 
   for (let i = 0; i < poolSize; i++) {
     yield* fork(startNextTask);
-  } // The saga will wait for all forked tasks to terminate before returning, because
+  }
+  // The saga will wait for all forked tasks to terminate before returning, because
   // fork() creates attached forks (in contrast to spawn()).
 }

frontend/javascripts/libs/utils.ts

@@ -964,6 +964,33 @@ export function chunkIntoTimeWindows<T>(
   );
 }
 
+// chunkDynamically takes an array of input elements and splits these
+// into batches. Instead of using a constant batch size, the elements
+// of a batch are measured with a measureFn. Then, each batch is filled
+// until the provided minThreshold is exceeded.
+// Note that the threshold will be exceeded for each batch
+// (except for the last batch which may contain less).
+export function chunkDynamically<T>(
+  elements: T[],
+  minThreshold: number,
+  measureFn: (el: T) => number,
+): Array<T[]> {
+  const batches = [];
+  let currentBatch = [];
+  let currentSize = 0;
+
+  for (let i = 0; i < elements.length; i++) {
+    currentBatch.push(elements[i]);
+    currentSize += measureFn(elements[i]);
+    if (currentSize > minThreshold || i === elements.length - 1) {
+      currentSize = 0;
+      batches.push(currentBatch);
+      currentBatch = [];
+    }
+  }
+  return batches;
+}
+
 export function convertBufferToImage(
   buffer: Uint8Array,
   width: number,