Support max_active_channels

will-moore · will-moore · commit aa308d186370 · 2025-01-09T09:00:13.000Z
diff --git a/src/app/context.js b/src/app/context.js
@@ -191,6 +191,16 @@ export default class Context {
       */
      luts = new Map();
 
+     /**
+      * max active channels
+      * 
+      * //  TODO: make the default configurable.
+      *
+      * @memberof Context
+      * @type {number}
+      */
+     max_active_channels = 20;
+
      /**
       * the lookup png
       *
@@ -243,6 +253,9 @@ export default class Context {
         // set up luts
         this.setUpLuts();
 
+        // load max active channels
+        this.loadMaxActiveChannels();
+
         // initialize Open_with
         OpenWith.initOpenWith();
 
@@ -344,6 +357,27 @@ export default class Context {
         });
     }
 
+    loadMaxActiveChannels() {
+        // query microservice endpoint...
+        let url = this.server + "/omero_ms_image_region/";
+        console.log(url);
+        fetch(url, {method: "OPTIONS"})
+        .then(r => r.json())
+        .then(data => {
+            console.log('data', data);
+            if (Number.isInteger(data.options?.maxActiveChannels)) {
+                this.max_active_channels = data.options.maxActiveChannels;
+                // in case the images loaded already (this query took longer than
+                // expected), let's update them...
+                for (let [id, conf] of this.image_configs) {
+                    conf.image_info.applyMaxActiveChannels(this.max_active_channels);
+                }
+            }
+        }).catch(() => {
+            console.log("failed to load omero_ms_image_region info");
+        });
+    }
+
     /**
      * Depending on what received as the inital parameters
      * (image(s), dataset, etc) we continue to create and add
diff --git a/src/model/image_info.js b/src/model/image_info.js
@@ -458,6 +458,9 @@ export default class ImageInfo {
         // If we've viewed this image before, apply cached settings
         this.applyCachedSettings(response);
 
+        // enforce max_active_channels
+        this.applyMaxActiveChannels(this.context.max_active_channels);
+
         // signal that we are ready
         this.ready = true;
         this.tmp_data = response;
@@ -470,6 +473,26 @@ export default class ImageInfo {
         this.requestDeltaT();
     }
 
+    applyMaxActiveChannels(max_active_channels) {
+        // let conf = this.context.getImageConfig(this.config_id);
+        console.log("applyMaxActiveChannels", max_active_channels, this.channels);
+        if (this.channels == null) {
+            return;
+        }
+        let channels = this.channels;
+        let activeCount = 0;
+
+        for (let i=0;i<channels.length;i++) {
+            let c = channels[i];
+            if (c.active) {
+                activeCount += 1;
+            }
+            if (activeCount > max_active_channels && c.active) {
+                c.active = false;
+            };
+        };
+    }
+
     /**
      * Gets cached image settings from context and updates our settings
      *
diff --git a/src/settings/channel-range.js b/src/settings/channel-range.js
@@ -18,6 +18,7 @@
 
 import Context from '../app/context';
 import Misc from '../utils/misc';
+import Ui from '../utils/ui';
 import {
     CHANNEL_SETTINGS_MODE, FLOATING_POINT_PRECISION, URI_PREFIX
 } from '../utils/constants';
@@ -543,6 +544,14 @@ export default class ChannelRange  {
         if (imgConf.image_info.model === 'greyscale' &&
             this.channel.active) return;
 
+        // don't allow to exceed max_active_channels
+        let maxActive = this.context.max_active_channels;
+        let activeCount = imgConf.image_info.channels.reduce((count, ch) => count + (ch.active ? 1 : 0), 0);
+        if (!this.channel.active && activeCount >= maxActive) {
+            Ui.showModalMessage(`The maximum number of active channels is ${maxActive}.`, "OK");
+            return;
+        }
+
         let history = [];
 
         // toggle channel active state
diff --git a/src/settings/channel-settings.js b/src/settings/channel-settings.js
@@ -18,7 +18,6 @@
 
 // js
 import Context from '../app/context';
-import Misc from '../utils/misc';
 import {inject, customElement, bindable, BindingEngine} from 'aurelia-framework';
 import {CHANNEL_SETTINGS_MODE, WEBGATEWAY} from '../utils/constants';
 import {
