This commit introduces Raycast, a Lua user object, which can be
used to perform a raycast on the map. The ray is continuable, so one can
also get hidden nodes (for example to see trough glass).
This is not really different from the light update of a voxel
manipulator. This update does not assume that the lighting was correct
before, therefore it is useful for correction.
Also expose this function to the Lua API for light correction, and
allow voxel manipulators not to update the light.
This commit introduces a new bulk node lighting algorithm to minimize
lighting bugs during l-system tree generation, schematic placement and
non-mapgen-object lua voxelmanip light calculation.
If the block above the changed area is not loaded, it gets loaded to avoid
lighting bugs.
Light is updated as soon as write_to_map is called on a voxel manipulator,
therefore update_map does nothing.
* Improved getPointedThing()
The new algorithm checks every node exactly once.
Now the point and normal vector of the collision is also returned in the
PointedThing (currently they are not used outside of the function).
Now the CNodeDefManager keeps the union of all possible nodeboxes, so
the raycast won't miss any nodes. Also if there are only small
nodeboxes, getPointedThing() is exceptionally fast.
Also adds unit test for VoxelLineIterator.
* Cleanup, code move
This commit moves getPointedThing() and
Client::getSelectedActiveObject() to ClientEnvironment.
The map nodes now can decide which neighbors they are connecting to
(MapNode::getNeighbors()).
This commit rewrites the procedure that is responsible for light
updating.
this commit
-provides iterative solutions for unlighting and light spreading
-introduces a new priority queue-like container for the iteration
-creates per-node MapBlock caching to reduce retrieving MapBlocks from
the map
-calculates with map block positions and in-block relative node
coordinates
-skips light updating if it is not necessary since the node's new light
will be the same as its old light was
