Differences

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--- buzz_examples [2016/09/02 13:28] – [Square Pattern Formation] ilpincy
+++ buzz_examples [2018/03/18 22:58] – root
@@ Line 77: / Line 77: @@
   var accum = neighbors.map(lj_vector).reduce(lj_sum, math.vec2.new(0.0, 0.0))
   if(neighbors.count() > 0)
-    math.vec2.scale(accum, neighbors.count())
+    math.vec2.scale(accum, 1.0 / neighbors.count())
   # Move according to vector
   goto(accum.x, accum.y)
@@ Line 98: / Line 98: @@
 ==== Square Pattern Formation ====
-<code buzz hexagon.bzz>
+To form square lattice, we can build upon the previous example. The insight is to notice that, in a square lattice, we can color the nodes forming the lattice with two shades, e.g., red and blue, and then mimic the [[http://www.metafysica.nl/turing/nacl_complex_motif_4.gif|crystal structure of kitchen salt]]. In this structure, if two nodes have different colors, they stay at a distance //D//; if they have the same color, they stay at a distance //D// * sqrt(2).
+With this idea in mind, the following script divides the robots in two swarms: those with an even id and those with an odd id. Then, using ''neighbors.kin()'' and ''neighbors.nonkin()'', the robots can distinguish which distance to pick and calculate the correct interaction vector.
+<code buzz square.bzz>
 # We need this for 2D vectors
 # Make sure you pass the correct include path to "bzzc -I <path1:path2> ..."
@@ Line 135: / Line 139: @@
   accum = neighbors.nonkin().map(lj_vector_nonkin).reduce(lj_sum, accum)
   if(neighbors.count() > 0)
-    math.vec2.scale(accum, neighbors.count())
+    math.vec2.scale(accum, 1.0 / neighbors.count())
   # Move according to vector
   goto(accum.x, accum.y)
@@ Line 158: / Line 162: @@
 }
 </code>
-===== Wheeled-robot Specific =====
-TODO
-===== Flying-robot Specific =====
-TODO