[Testbed] Fixed condition when to use higher diff-threshold in MipMap…

…s test.

The condition for the difference threshold depends on the texture extent being a non-power-of-two (NPOT) texture.
This condition was erroneously always true.

tests/Testbed/UnitTests/TestMipMaps.cpp

@@ -26,7 +26,7 @@ static bool IsPowerOfTwo(std::uint32_t x)
 
 static bool IsPowerOfTwoExtent(const Extent3D& extent)
 {
-    return (IsPowerOfTwo(extent.width) || IsPowerOfTwo(extent.height) || IsPowerOfTwo(extent.depth));
+    return (IsPowerOfTwo(extent.width) && IsPowerOfTwo(extent.height) && IsPowerOfTwo(extent.depth));
 }
 
 DEF_TEST( MipMaps )
@@ -45,7 +45,7 @@ DEF_TEST( MipMaps )
           For future improvements, these backends could provide MIP-map generation via image-blit functionality to compute a perfect reduction filter (i.e. no undersampling).
           This could be enabled via a new MiscFlags entry, for example: MiscFlags::HighQualityMipFilter.
         */
-        const bool isNpotTexture = IsPowerOfTwoExtent(texDesc.extent);
+        const bool isNpotTexture = !IsPowerOfTwoExtent(texDesc.extent);
         const int diffThreshold = (isNpotTexture ? 170 : 2);
 
         for_subrange(mip, 1, texDesc.mipLevels)