The function dynamic_add_media() was changed in incompatible ways in
several minor versions of Minetest, breaking the display of handheld
maps in Minetest 5.5.0. This patch makes handheld maps display there.
The function was blocking with one argument in Minetest 5.3. It was also
blocking in Minetest 5.4, but took an additional argument for a function
to execute once the media had been received. Calling dynamic_add_media()
with a single argument had been deprecated; a function that did nothing
was provided in mcl_maps to satisfy the changed argument requirements.
In Minetest 5.5, dynamic_add_media() was changed to non-blocking. This
introduced a race condition in mcl_maps, where a client often tried to
display a map before it had received the map texture from the server.
Opening an issue on the Minetest issue tracker led to it being closed in
about 20 minutes: <https://github.com/minetest/minetest/issues/11997>
Redstone comparators have two modes, comparison mode & subtraction mode.
Before this patch, the functions to turn comparators on or off attempted
to swap nodes with comparators in the same mode, but failed to determine
the correct replacement node, if the existing node was not a comparator.
When a comparator in an on state (e.g. powered by a filled cauldron) was
flooded, the flooding dropped the comparator and replaced the comparator
node that was to be swapped out with air, which lead to a server crash.
This patch changes the functions that turn comparators on or off so they
only swap existing nodes with comparators in the same mode if the name
of the replacement node can be determined – i.e. if it is not nil.
In commit 55009c257e253c49dacf017e4bd56bc36aca2e10 that added vectors to
mcl_composters, mcl_hoppers was accidentally patched with a unrelated
change, updating it to get_item_group(). This mostly works, but in one
particular case the semantics of the return value differs. Instead of
returning 'nil' it returns '0'. That altered the evaluation of an if
condition, breaking the abm that sucks in items.
This commit fixes the conditional by explicitly comparing '~= 0'.
