Fix proofreading when mag 1 doesn't exist for segmentation layer

CHANGELOG.unreleased.md

@@ -40,6 +40,7 @@ For upgrade instructions, please check the [migration guide](MIGRATIONS.released
 - Fixed a bug where the dataset folders view would not list public datasets if the requesting user could not also access the dataset for other reasons, like being admin. [#6759](https://github.com/scalableminds/webknossos/pull/6759)
 - Fixed a bug where zarr-streamed datasets would produce (very rare) rendering errors. [#6782](https://github.com/scalableminds/webknossos/pull/6782)
 - Fixed a bug where publicly shared annotations were not viewable by users without an account. [#6784](https://github.com/scalableminds/webknossos/pull/6784)
+- Fixed proofreading when mag 1 doesn't exist for segmentation layer [#6795](https://github.com/scalableminds/webknossos/pull/6795)
 - Fixed that the proofreading tool allowed to split/merge with segment 0 which led to an inconsistent state. [#6793](https://github.com/scalableminds/webknossos/pull/6793)
 
 ### Removed

frontend/javascripts/oxalis/api/api_latest.ts

@@ -66,7 +66,6 @@ import {
 } from "oxalis/model/accessors/volumetracing_accessor";
 import { getHalfViewportExtentsFromState } from "oxalis/model/sagas/saga_selectors";
 import {
-  getDatasetResolutionInfo,
   getLayerBoundaries,
   getLayerByName,
   getResolutionInfo,
@@ -1549,10 +1548,12 @@ class DataApi {
     topLeft: Vector3,
     bottomRight: Vector3,
     token: string,
+    resolution?: Vector3,
   ): string {
     const { dataset } = Store.getState();
-    const resolutionInfo = getDatasetResolutionInfo(dataset);
-    const resolution = resolutionInfo.getLowestResolution();
+    const resolutionInfo = getResolutionInfo(getLayerByName(dataset, layerName, true).resolutions);
+    resolution = resolution || resolutionInfo.getLowestResolution();
+
     const magString = resolution.join("-");
     return (
       `${dataset.dataStore.url}/data/datasets/${dataset.owningOrganization}/${dataset.name}/layers/${layerName}/data?mag=${magString}&` +
@@ -1591,13 +1592,15 @@ class DataApi {
     layerName: string,
     topLeft: Vector3,
     bottomRight: Vector3,
+    resolution?: Vector3,
   ): Promise<ArrayBuffer> {
     return doWithToken((token) => {
       const downloadUrl = this._getDownloadUrlForRawDataCuboid(
         layerName,
         topLeft,
         bottomRight,
         token,
+        resolution,
       );
       return Request.receiveArraybuffer(downloadUrl);
     });

frontend/javascripts/oxalis/model/accessors/dataset_accessor.ts

@@ -368,11 +368,19 @@ function _getResolutionInfoOfVisibleSegmentationLayer(state: OxalisState): Resol
 export const getResolutionInfoOfVisibleSegmentationLayer = memoizeOne(
   _getResolutionInfoOfVisibleSegmentationLayer,
 );
-export function getLayerByName(dataset: APIDataset, layerName: string): DataLayerType {
+export function getLayerByName(
+  dataset: APIDataset,
+  layerName: string,
+  alsoMatchFallbackLayer: boolean = false,
+): DataLayerType {
   const dataLayers = getDataLayers(dataset);
   const hasUniqueNames = _.uniqBy(dataLayers, "name").length === dataLayers.length;
   ErrorHandling.assert(hasUniqueNames, messages["dataset.unique_layer_names"]);
-  const layer = dataLayers.find((l) => l.name === layerName);
+  const layer = dataLayers.find(
+    (l) =>
+      l.name === layerName ||
+      (alsoMatchFallbackLayer && "fallbackLayer" in l && l.fallbackLayer === layerName),
+  );
 
   if (!layer) {
     throw new Error(`Layer "${layerName}" not found`);

frontend/javascripts/oxalis/model/sagas/proofread_saga.ts

@@ -699,6 +699,7 @@ function* createGetUnmappedDataValueFn(
       fallbackLayerName,
       nodePosition,
       V3.add(nodePosition, mag),
+      mag,
     );
 
     return Number(new TypedArrayClass(buffer)[0]);