Primarily for crossing cell border case. Each Navigator::update call has a cost.
Doing it multiple times per frame increased frame duration on cell loading.
Call Navigator::wait only when cell has changed but do not use
Scene::hasCellChanged because it doesn't always indicates it.
Actors may have different collision shapes. Currently there are axis-aligned
bounding boxes and rotating bounding boxes. With AABB it's required to use
bounding cylinder for navmesh agent to avoid providing paths where actor can't
pass. But for rotating bounding boxes cylinder with diameter equal to the front
face width should be used to not reduce of available paths. For example rats
have rotating bounding box as collision shape because of the difference between
front and side faces width.
* Add agent bounds to navmesh tile db cache key. This is required to distinguish
tiles for agents with different bounds.
* Increase navmesh version because navmesh tile db cache key and data has changed.
* Move navmesh version to the code to avoid misconfiguration by users.
* Fix all places where wrong half extents were used for pathfinding.
Use "pragma max_page_count" to define max allowed file size in combination with
"pragma page_size" based on a new setting "max navmeshdb file size".
* Stop navmeshtool on the first db error.
* Disable writes to db in the engine on first "database or disk is full"
SQLite3 error. There is no special error code for this error.
* Change default "write to navmeshdb" to true.
* Use time intervals for transaction duration instead of number of changes.
Perform all request to db in a single thread to avoid blocking navmesh
generator threads due to slow write operations.
Write to db navmesh for all changes except update as it done for memory cache.
Batch multiple db operations into a single transaction to speed up writing by
not executing fsync after each insert/update query. All reads are performed in
the same transaction so they see uncommited data.
Even when target is not reachable actor will try to run there either because
target navmesh polygon is selected within extended area or because partial path
is built to the closest possible polygon.
Add special loading progress bar.
It should be fast enough to not keep loading screen for noticably long but
will provide better pathfinding for actors inside interior cells.
This AABB tree required when need to filter out input mesh that has not
influence navmesh tile output. This filtering is already done before. Each
recast mesh corresponds to a single navmesh tile and has appropriate bounds.
To avoid triggering NavMesh update when RecastMesh change should not change
NavMesh.
Based on the following assumption:
Given a set of transformations and a bounding shape for all these
tranformations, a new object transformation that does not change this
bounding shape also should not change navmesh if for all of this object
transformations resulting navmesh tiles are equivalent
The idea is to report back to RecastMeshManager all changes of NavMesh if there
are any assiciated with RecastMesh version. So we know the last time when
RecastMesh change resulted into the NavMesh change. When later report shows
that there was no NavMesh change for a new RecastMesh version we can assume
that any object transformation within the same bounding box should not change
NavMesh.
When there is only one actor (player) on a scene and it moving to other
cell first it will be removed from navigator then added. Remove cause
navmesh removing for its half extents. After it is added navmesh for
same half extents is created and added. While this all happens there are
still jobs for old navmesh are processing. Old navmesh still exists
because it is stored by shared pointer. So jobs take tiles from cache
and place them into old navmesh. After that other jobs take same tiles
from cache (half extents and coordinates are equal) and place them into
other navmesh. dtNavMesh changes tile data on add and remove. Adding tile
to two dtNavMesh corrupts tile in both nameshes.
