init

.gitignore

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+*.lua

src/main.moon

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+width, height = love.graphics.getDimensions!
+rng = love.math.newRandomGenerator 0
+types = 7
+radius = 4
+colors = {}
+interactions = {}
+universe = {}
+
+physics = (a, b) ->
+  dx = a.x - b.x
+  dy = a.y - b.y
+  ds = dx * dx + dy * dy
+  theta = math.atan2 dy, dx
+  x = math.cos theta
+  y = math.sin theta
+
+  f = interactions["#{a.n}.#{b.n}"](ds)
+  a.vx += f * x
+  a.vy += f * y
+
+  f = interactions["#{b.n}.#{a.n}"](ds)
+  b.vx += f * x
+  b.vy += f * y
+
+for a = 1, types
+  for b = 1, types
+    A = rng\randomNormal 0.5, 0
+    aa = rng\randomNormal 5, 10
+    B = rng\randomNormal 0.5, 0
+    bb = rng\randomNormal 5, 10
+    interactions["#{a}.#{b}"] = (ds) ->
+      if ds < radius^0.5
+        return 1 / ds
+      else
+        return A * (ds^0.5 - aa)
+    interactions["#{b}.#{a}"] = (ds) ->
+      if ds < radius^0.5
+        return 1 / ds
+      else
+        return B * (ds^0.5 - bb)
+
+-- for k,v in pairs interactions
+--   print k,v
+
+for a = 1, types
+  colors[a] = { rng\random!, rng\random!, rng\random!, 1 }
+
+class Particle
+  new: (@n=1, x, y) =>
+    @x = x or love.math.random 0, width
+    @y = y or love.math.random 0, height
+    @vx = 0
+    @vy = 0
+
+for i=1, 2
+  table.insert universe, Particle(love.math.random 1, types)
+
+love.update = (dt) ->
+  for a = 1, #universe - 1
+    for b = a + 1, #universe
+      physics(universe[a], universe[b])
+
+  for particle in *universe
+    particle.vx *= 0.01
+    particle.vy *= 0.01
+    particle.x += particle.vx * dt
+    particle.y += particle.vy * dt
+
+love.draw = ->
+  for particle in *universe
+    love.graphics.setColor colors[particle.n]
+    love.graphics.circle "fill", particle.x, particle.y, radius
+
+love.keypressed = (key) ->
+  love.event.quit! if key == "escape"