snakenet.rb: You can choose between using float or integer weights. floats seem to give better results and the speed didn't improve a lot.

src/tools/snakenet/snakenet.rb

@@ -4,6 +4,7 @@ require 'pp'
 require 'thread/pool'
 
 GAMES_PER_ROUND = 50
+FLOAT = true
 
 class Game
 	WIDTH = 16
@@ -177,10 +178,10 @@ class AI
 		@rounds = 1
 		@id = rand(0xFFFFFF)
 		if w==nil
-			@weights = Array.new(network_size()) { rand() * 2.0 - 1.0 }
+			@weights = Array.new(network_size()) { FLOAT ? rand() * 2.0 - 1.0 : rand(256) - 128 }
 			puts "Initialized with random values: #{@weights}" if @debug
 		else
-			if w[0].is_a? Integer
+			if w[0].is_a?(Integer) && FLOAT
 				@weights = w.map{|s| s.to_s(16).rjust(8, "0").split("").each_slice(2).to_a.map(&:join).map{|s| s.to_i(16).chr}.join.unpack("g")}.flatten
 			else
 				@weights = w
@@ -220,7 +221,7 @@ class AI
 		(1...(NETWORK_LAYOUT.count)).each do |i|
 			c_in = NETWORK_LAYOUT[i-1]
 			c_out = NETWORK_LAYOUT[i]
-			outputs = Array.new(c_out){0.0}
+			outputs = Array.new(c_out){FLOAT ? 0.0 : 0}
 			(0...c_out).each do |o|
 				(0...c_in).each do |i|
 					outputs[o] += inputs[i] * @weights[x]
@@ -253,33 +254,53 @@ class AI
 		#	w[i2] = temp
 		if action==0 #change single value
 			i = rand(network_size())
-			diff = rand() * 0.2 - 0.1
+			diff = FLOAT ? rand() * 0.2 - 0.1 : rand(256) - 128
 			w2 = w.dup
 			w[i] += diff
+			if FLOAT
 				w[i] = 1.0 if w[i]>1.0
 				w[i] = -1.0 if w[i]<-1.0
+			else
+				w[i] = 127 if w[i]>127
+				w[i] = -128 if w[i]<-128
+			end
 			w2[i] -= diff
+			if FLOAT
 				w2[i] = 1.0 if w2[i]>1.0
 				w2[i] = -1.0 if w2[i]<-1.0
+			else
+				w2[i] = 127 if w2[i]>127
+				w2[i] = -128 if w2[i]<-128
+			end
 			return [AI.new(w), AI.new(w2)]
 		elsif action==1 #invert single value
 			i = rand(network_size())
-			w[i] *= -1.0
+			w[i] *= FLOAT ? -1.0 : -1
 		elsif action==2
 			(0...network_size()).each do |i|
-				w[i] = rand() * 2 - 1.0 if rand(5)==0
+				w[i] = (FLOAT ? rand() * 2 - 1.0 : rand(256) - 128) if rand(5)==0
 			end
 		else #change multiple values
 			w2 = w.dup
 			(0...network_size()).each do |i|
 				if (rand(5)==0)
-					diff = rand() * 0.2 - 0.1
+					diff = FLOAT ? rand() * 0.2 - 0.1 : rand(256) - 128
 					w[i] += diff
+					if FLOAT
 						w[i] = 1.0 if w[i]>1.0
 						w[i] = -1.0 if w[i]<-1.0
+					else
+						w[i] = 127 if w[i]>127
+						w[i] = -128 if w[i]<-128
+					end
 					w2[i] -= diff
+					if FLOAT
 						w2[i] = 1.0 if w2[i]>1.0
 						w2[i] = -1.0 if w2[i]<-1.0
+					else
+						w2[i] = 127 if w2[i]>127
+						w2[i] = -128 if w2[i]<-128
+					end
 				end
 			end
 			return [AI.new(w), AI.new(w2)]
@@ -303,13 +324,17 @@ class AI
 		w = @weights.dup
 		w2 = ai.weights
 		(0...network_size()).each do |i|
-			w[i] = (w[i] + w2[i]) / 2.0
+			w[i] = (w[i] + w2[i]) / (FLOAT ? 2.0 : 2)
 		end
 		return AI.new(w)
 	end
 	
 	def dump
+		if FLOAT
 			puts "const uint32_t _weights[#{network_size()}] = {#{@weights.map{|x| "0x" + [x].pack('g').split("").map(&:ord).map{|i| i.to_s(16).rjust(2, '0')}.join}.join(", ")}};"
+		else
+			puts "const int8_t _weights[#{network_size()}] = {#{@weights.join(", ")}};"
+		end
 		#puts "Simplified: #{simplified}"
 	end
 end