#984 Bigface's head is treated differently in Fog of War

[Sebastian Andersson]

With the latest revision in server's master (85f42244a4670ce8cc5391242a4af3f088e46ea8) a big face's head tile is treated differently than its other tiles when in fog of war.
The bottom layer tile is cleared, the head is told to be rendered at full brightness.
The other tiles of it are rendered in the correct brightness.

See attached picture from Scorn at night.

This doesn't seem to be a client issue, there comes a map2 command from the server that tells it to clear the first layer on the head tile, but not the others that are out of sight/in fog of war.

[Sebastian Andersson]

I see this is a result of the protocol limitation, where big face objects are sent to the head, but the client don't know if that cell should be shown or not. When the head cell goes out of view, but there are still tail cells in view, the server sends clear and an update to the big face object's head cell.

It was the gtk client that the screenshot was from.

If there can only be one big face object on a cell, the client can use the fact that only one layer is used and if it contains a big face object, then it can be assumed the cell should transition to fog of war data. This doesn't work if all objects on a cell are big face objects, or if it can only contain a single big face object. For that to be handled correctly, a protocol update is needed.