Addition of private helper debug only function to help guard against destroyed objects being used.

rollup.config.mjs

@@ -254,6 +254,7 @@ const moduleOptions = buildType => ({
 const stripFunctions = [
     'Debug.assert',
     'Debug.assertDeprecated',
+    'Debug.assertDestroyed',
     'Debug.call',
     'Debug.deprecated',
     'Debug.warn',
@@ -265,6 +266,7 @@ const stripFunctions = [
     'Debug.trace',
     'DebugHelper.setName',
     'DebugHelper.setLabel',
+    `DebugHelper.setDestroyed`,
     'DebugGraphics.toString',
     'DebugGraphics.clearGpuMarkers',
     'DebugGraphics.pushGpuMarker',

src/core/debug.js

@@ -51,6 +51,22 @@ class Debug {
         }
     }
 
+    /**
+     * Assertion error message that writes an error message to the log if the object has already
+     * been destroyed. To be used along setDestroyed.
+     *
+     * @param {object} object - The object to check.
+     */
+    static assertDestroyed(object) {
+        if (object?.__alreadyDestroyed) {
+            const message = `[${object.constructor?.name}] with name [${object.name}] has already been destroyed, and cannot be used.`;
+            if (!Debug._loggedMessages.has(message)) {
+                Debug._loggedMessages.add(message);
+                console.error('ASSERT FAILED: ', message, object);
+            }
+        }
+    }
+
     /**
      * Executes a function in debug mode only.
      *
@@ -169,6 +185,17 @@ class DebugHelper {
             object.label = label;
         }
     }
+
+    /**
+     * Marks object as destroyed. Executes only in the debug build. To be used along assertDestroyed.
+     *
+     * @param {object} object - The object to mark as destroyed.
+     */
+    static setDestroyed(object) {
+        if (object) {
+            object.__alreadyDestroyed = true;
+        }
+    }
 }
 
 export { Debug, DebugHelper };

src/platform/graphics/render-target.js

@@ -1,4 +1,4 @@
-import { Debug } from '../../core/debug.js';
+import { Debug, DebugHelper } from '../../core/debug.js';
 import { TRACEID_RENDER_TARGET_ALLOC } from '../../core/constants.js';
 import { PIXELFORMAT_DEPTH, PIXELFORMAT_DEPTHSTENCIL } from './constants.js';
 import { DebugGraphics } from './debug-graphics.js';
@@ -167,6 +167,8 @@ class RenderTarget {
 
             this.destroyFrameBuffers();
         }
+
+        DebugHelper.setDestroyed(this);
     }
 
     /**
@@ -206,6 +208,7 @@ class RenderTarget {
      * @ignore
      */
     init() {
+        Debug.assertDestroyed(this);
         this.impl.init(this._device, this);
     }