Inner up-facing water surface should be visible for floating blocks of water

See images:

<img width="854" height="480" alt="Image" src="https://github.com/user-attachments/assets/8fe32085-cabf-471c-9916-d5b2477cbf34" />
<img width="854" height="480" alt="Image" src="https://github.com/user-attachments/assets/9ace30fe-a6dd-407b-989d-9053546a535a" />