This has been discussed in the BYONDiscord before but posting it here so it doesn't get forgotten.

Currently setting map_format to SIDE_MAP makes the SEE_BLACKNESS sight flag do nothing. This can be inconvenient for example because you might want to hide objects that partially overlay with tiles you can see but the rest of them is on unseen tiles.

I propose that blackness is still rendered with the SEE_BLACKNESS flag on SIDE_MAP map format, one issue that arises is the choice of the layer of the blackness. As suggested by the user Constable@ssbutt one way to solve that is to add either global or /client vars blackness_plane and blackness_layer to control how the blackness is rendered. This could be useful but for our purpose even having the blackness render on a fixed layer and plane with SIDE_MAP would be sufficient.