rts

to run: npm start (starts BE and also serves FE)

• uses paper.js and socket.io

dev

To add a new unit attribute:

1. add it to the consts in ./public/constants.js
2. update the calcCost function on both backend and frontend
3. implement its behavior

To add a new action type:

1. add it to the ACTION_TYPES enum in ./public/constants.js
2. add a handler in handlePlayerAction() in ./game/game.js
3. add a frontend way to call emitAction(ACTION_TYPES.[your_action_type])

For hot reloading, see this section.

thoughts on unit balance

for a given range/speed/turn/rof invariant, let (d,h) represent a unit w/ d=damage, h=health, the cost efficiency rock-paper-scissors cycle is as follows:

• suppose a base unit B = (10,10)
• B < (10,1) < (1,1) < (1,10) < B

known bugs

main todos

• HIGH priority

  • implement ControlPointsCaptured unit historical stat
  • set unit to also prioritize units that pose a threat to it first in addition to above (prioritize threats)
  • [ongoing] unit balance :)
  • load from export file...
  • make death explosions w/ tween :)
  • show turn resolve summary/highlights
  • diagonal panning (n-key rollover?)

• MID priority

  • make UI preview units in blueprint + unit fac choice...
  • support both manual + AI targetting simultaneously
  • better collision resolution
  • enable placing more factories
  • more map types {height, width, control points}
  • make factories destructable
    • need to make facs buildable first...
  • add ability to unlock higher limits for certain stats?? (like researching tech)
  • huge refactor for readability?

• LOW priority

  • better unit visuals based on unit class (artillery, tanky, raider, scout, balanced)
  • maybe different pricing formulas based on unit class?
  • more unit stats
    • sight radius?
    • AOE
    • short/long reload...
    • healing per sec
  • all units to show healthbars
  • factory upgrade build speed, build radius
    • factory choose where to build unit
  • use more backend validation instead of frontend validation

Misc notes:

• a lot of hacks/simple tricks are possible simply b/c it's small scale (< 50 units usually)

• Victor.js is mutable, modifies vector directly unless you use .clone()

Hot reloading everything

• Frontend doesn't use hot-reload per-se, but preserves state across reloads because of custom server-side socket.io reconnect logic
• Backend uses node-hot for hot-reloading file changes in ./game without restarting server.
  • Also can tolerate errors (fix the error, then press enter in console to continue game)
• Frontend hot-reload uses webpack-hot-middleware
  • can't use Parcel for FE b/c v1 trips on sourcemaps so can't import paper
  • parcel2 issues here

2d engines compared:

• perf-wise, https://github.com/slaylines/canvas-engines-comparison says most things are pretty decent at 5k moving entities.

• in hindsight, should've used Fabric.js http://fabricjs.com/fabric-intro-part-1#why_fabric which is much better maintained, also has scenegraph + collisions via intersection

  • docs are crappy though...

• paper js - has vector lib, lots of demos, has scenegraph, has efficient sweep+Prune collision detection paperjs/paper.js#1737
  • collisions - http://paperjs.org/reference/item/#intersects-item
• two js - focuses on animation, has basic vector lib, has scenegraph, but doesn't have mouse event support for actual entities, bad docs
• pixi js - just rendering, not enough, has collision detect?
• stage js - not actively developed, no vector lib, has scenegraph, bad docs
• pencil js - bad docs
• p5.js - ??

vector engines compared:

• b/c paper JS's vector point stuff doesn't really work...
• https://github.com/evanshortiss/vector2d
• ended up using http://victorjs.org/