Fix gammeSpace property not being set correctly

src/Materials/Textures/baseTexture.ts

@@ -233,6 +233,7 @@ export class BaseTexture implements IAnimatable {
         this._texture.is2DArray = value;
     }
 
+    private _gammaSpace = true;
     /**
      * Define if the texture contains data in gamma space (most of the png/jpg aside bump).
      * HDR texture are usually stored in linear space.
@@ -240,18 +241,32 @@ export class BaseTexture implements IAnimatable {
      */
     @serialize()
     public get gammaSpace(): boolean {
-        return this._texture?._gammaSpace ?? true;
+        if (!this._texture) {
+            return this._gammaSpace;
+        } else {
+            if (this._texture._gammaSpace === null) {
+                this._texture._gammaSpace = this._gammaSpace;
+            }
+        }
+
+        return this._texture._gammaSpace;
     }
 
     public set gammaSpace(gamma: boolean) {
-        if ((this._texture?._gammaSpace ?? gamma) === gamma) {
-            return;
-        }
+        if (!this._texture) {
+            if (this._gammaSpace === gamma) {
+                return;
+            }
 
-        if (this._texture) {
+            this._gammaSpace = gamma;
+        } else {
+            if (this._texture._gammaSpace === gamma) {
+                return;
+            }
             this._texture._gammaSpace = gamma;
-            this._markAllSubMeshesAsTexturesDirty();
         }
+
+        this._markAllSubMeshesAsTexturesDirty();
     }
 
     /**

src/Materials/Textures/internalTexture.ts

@@ -254,7 +254,7 @@ export class InternalTexture {
     public _references: number = 1;
 
     /** @hidden */
-    public _gammaSpace = true;
+    public _gammaSpace: Nullable<boolean> = null;
 
     private _engine: ThinEngine;