* Implement the handler code for `return false` when actors are
colliding with each other and wish to act like solid walls.
* The locked doors will `return false` when they're closed and the
colliding actor does not have the matching key.
* Add arbitrary key/value storage to Actors. The colored keys will set
an actor value "key:%TITLE%" on the one who touched the key before
destroying itself. The colored doors check that key when touched to
decide whether to open.
* The trapdoor now only opens if you're touching it from the top (your
overlap box Y value is 0), but if you touch it from below and the door
is closed, it acts like a solid object.
* Add some encoding/decoding functions for binary msgpack format for
levels and doodads. Currently it writes msgpack files that can be
decoded and printed by Python (mp2json.py) but it can't re-read from
the binary format. For now, levels will continue to write in JSON
format.
* Add filesystem abstraction functions to the balance/ package to search
multiple paths to find Levels and Doodads, to make way for
system-level doodads.
Fixes:
* Move the call to CollidesWithGrid() inside the Canvas instead of
outside in the PlayScene.movePlayer() so it can apply to all Actors
in motion.
* PlayScene.movePlayer() in turn just sets the player's Velocity so the
Canvas.Loop() can move the actor itself.
* When keeping the player inside the level boundaries: previously it was
assuming the player Position was relative to the window, and was
checking the WorldIndexAt and getting wrong results.
* Canvas scrolling (loopFollowActor): check that the actor is getting
close to the screen edge using the Viewport into the world, NOT the
screen-relative coordinates of the Canvas bounding boxes.
Noah