Wheelchair Accessible bathroom

The use of a classic accessible bathroom usually involves several successive transfers (to the toilet, to the shower or bath, etc.). Furthermore, it does not provide a comfortable solution for drying after bathing. This can be solved by a platform where on one side the person washes under the shower and then slides across to the other side, which is dry, where the person can get dry and eventually get dressed. If the toilet is at one end of this platform, one can perform all personal hygiene activities with only two transfers (from the chair to the platform, from the platform for the chair).
In the case of a person with amputation or atrophy of the lower limbs (Polio, for example), it is even more comfortable to raise a shower base and install it at the platform level (the same level of the wheelchair), since the person tends to bathe sitting with legs crossed (and it is not comfortable having them hanging as it happens when one is sitting on a shower bench). Of course, this solution is "tailor-made" and is not easily usable by other family members.
The bathroom of the photos below had several constraints from the point of view of materials (wood floor, fragile wall) and dimensions: it was intended to make a bedroom with walk-in closet and a bathroom, with circulation space for a wheelchair, in an area of about 3,80cmx4,50cm (indicative dimensions and drawing). The concept is much easier to achieve with more common materials and in a larger space.