Fix dispose mrt

dist/preview release/what's new.md

@@ -275,6 +275,7 @@
 - Fix for triggering interactions on nearby meshes when performing a near interaction grab ([rickfromwork](https://github.com/rickfromwork))
 - Fix for near interaction failing when multiple utility layers are present ([rickfromwork](https://github.com/rickfromwork))
 - Fix handling of events to support multiple canvas scenarios DeviceInputSystem ([PolygonalSun](https://github.com/PolygonalSun))
+- Fix undisposed textures in PrePass effects that would cause the scene to have more textures than expected ([CraigFeldspar](https://github.com/CraigFeldspar))
 
 ## Breaking changes
 

src/Materials/Textures/multiRenderTarget.ts

@@ -204,6 +204,7 @@ export class MultiRenderTarget extends RenderTargetTexture {
         this._createInternalTextures();
 
         if (forceFullRebuild) {
+            this._releaseTextures();
             this._createTextures();
         }
 
@@ -224,6 +225,14 @@ export class MultiRenderTarget extends RenderTargetTexture {
         this._texture = this._internalTextures[0];
     }
 
+    private _releaseTextures(): void {
+        if (this._textures) {
+            for (let i = 0; i < this._textures.length; i++) {
+                this._textures[i].dispose();
+            }
+        }
+    }
+
     private _createTextures(): void {
         this._textures = [];
         for (var i = 0; i < this._internalTextures.length; i++) {
@@ -308,7 +317,7 @@ export class MultiRenderTarget extends RenderTargetTexture {
      */
     public dispose(): void {
         this.releaseInternalTextures();
-
+        this._releaseTextures();
         super.dispose();
     }
 
@@ -325,6 +334,7 @@ export class MultiRenderTarget extends RenderTargetTexture {
                 this._internalTextures[i].dispose();
                 this._internalTextures.splice(i, 1);
             }
+            this._textures[i]._texture = null;
         }
     }
 }

src/Materials/Textures/prePassRenderTarget.ts

@@ -127,5 +127,9 @@ export class PrePassRenderTarget extends MultiRenderTarget {
         if (this.imageProcessingPostProcess) {
             this.imageProcessingPostProcess.dispose();
         }
+
+        if (this.renderTargetTexture) {
+            this.renderTargetTexture._prePassRenderTarget = null;
+        }
     }
 }

src/Rendering/prePassRendererSceneComponent.ts

@@ -37,7 +37,7 @@ declare module "../abstractScene" {
 declare module "../Materials/Textures/renderTargetTexture" {
     export interface RenderTargetTexture {
         /** @hidden */
-        _prePassRenderTarget: PrePassRenderTarget;
+        _prePassRenderTarget: Nullable<PrePassRenderTarget>;
     }
 }