Finally add a second option for Chunk MapAccessor implementation besides the
MapAccessor. The RLEAccessor is basically a MapAccessor that will compress
your drawing with Run Length Encoding (RLE) in the on-disk format in the ZIP
file.
This slashes the file sizes of most levels:
* Shapeshifter: 21.8 MB -> 8.1 MB
* Jungle: 10.4 MB -> 4.1 MB
* Zoo: 2.8 MB -> 1.3 MB
Implementation details:
* The RLE binary format for Chunks is a stream of Uvarint pairs storing the
palette index number and the number of pixels to repeat it (along the Y,X
axis of the chunk).
* Null colors are represented by a Uvarint that decodes to 0xFFFF
or 65535 in decimal.
* Gameplay logic currently limits maps to 256 colors.
* The default for newly created chunks in-game will be RLE by default.
* Its in-memory representation is still a MapAccessor (a map of absolute
world coordinates to palette index).
* The game can still open and play legacy MapAccessor maps.
* On save in the editor, the game will upgrade/convert MapAccessor chunks over
to RLEAccessors, improving on your level's file size with a simple re-save.
Current Bugs
* On every re-save to RLE, one pixel is lost in the bottom-right corner of
each chunk. Each subsequent re-save loses one more pixel to the left, so what
starts as a single pixel per chunk slowly evolves into a horizontal line.
* Some pixels smear vertically as well.
* Off-by-negative-one errors when some chunks Iter() their pixels but compute
a relative coordinate of (-1,0)! Some mismatch between the stored world coords
of a pixel inside the chunk vs. the chunk's assigned coordinate by the Chunker:
certain combinations of chunk coord/abs coord.
To Do
* The `doodad touch` command should re-save existing levels to upgrade them.
Add new doodads:
* Start Flag: place this in a level to set the spawn point of the player
character. If no flag is found, the player spawns at 0,0 in the top
corner of the map. Only use one Start Flag per level, otherwise the
player will randomly spawn at one of them.
* Crumbly Floor: a solid floor that begins to shake and then fall apart
after a moment when a mobile character steps on it. The floor respawns
after 5 seconds.
* State Blocks: blue and orange blocks that toggle between solid and
pass-thru whenever a State Button is activated.
* State Button: a solid "ON/OFF" block that toggles State Blocks back
and forth when touched. Only activates if touched on the side or bottom;
acts as a solid floor when walked on from the top.
New features for doodad scripts:
* Actor scripts: call SetMobile(true) to mark an actor as a mobile mob
(i.e. player character or enemy). Other doodads can check if the actor
colliding with them IsMobile so they don't activate if placed too close
to other (non-mobile) doodads in a level. The Blue and Red Azulians
are the only mobile characters so far.
* Message.Broadcast allows sending a pub/sub message out to ALL doodads
in the level, instead of only to linked doodads as Message.Publish does.
This is used for the State Blocks to globally communicate on/off status
without needing to link them all together manually.
