From 075c0f88d6af832b5af3232c9da28f3eeca39da5 Mon Sep 17 00:00:00 2001
From: Sarah Jamie Lewis <sarah@openprivacy.ca>
Date: Tue, 1 Oct 2019 12:10:48 -0700
Subject: [PATCH] Much more accurate Snowflake Model

---
 experiments/snowball/main.go | 48 +++++++++++++++++-------------------
 1 file changed, 23 insertions(+), 25 deletions(-)

diff --git a/experiments/snowball/main.go b/experiments/snowball/main.go
index effae83..047a3a8 100644
--- a/experiments/snowball/main.go
+++ b/experiments/snowball/main.go
@@ -15,21 +15,26 @@ var initialSureness = flag.Int("initialSureness", 2, "how sure an honest node is
 var byzantineTurtles = flag.Int("byzantineTurtles", 50, "in consensus simlulations, the number of turtles who will always vote 2")
 var cleverByzantineTurtles = flag.Bool("cleverByzantineTurtles", true, "byzantine turtles try to find each other")
 
+var alpha = flag.Float64("alpha", 0.5, "the proportion of votes in a voting round that a color must have before it is considered a vote for that colour")
+
+
 type Snowball struct {
 	color       int
 	Probability float64
 	sureness    float32
 	Byztantine  bool
+	colourCounts []int
 }
 
 func (sm *Snowball) Setup(env *core.Environment, t *core.Turtle) {
 	num := rand.Intn(100)
 	if num >= int(sm.Probability*100.0) {
-		sm.color = 2
-	} else {
 		sm.color = 1
+	} else {
+		sm.color = 0
 	}
 	sm.sureness = float32(*initialSureness)
+	sm.colourCounts = make([]int,2)
 }
 
 func (sm *Snowball) GetColor() int {
@@ -44,7 +49,7 @@ func (sm *Snowball) Run(env *core.Environment, t *core.Turtle) {
 			t.FollowGradient(env, 5, 2, "3")
 			t.Drop(env, 1, "3")
 		}
-		sm.color = 2
+		sm.color = 1
 		t.SetColor(color.RGBA{255, 0, 0, 0})
 		t.Drop(env, 1, "2")
 
@@ -57,31 +62,24 @@ func (sm *Snowball) Run(env *core.Environment, t *core.Turtle) {
 		t.Wiggle()
 		am1 := t.AmountAll(env, 1, "1")
 		am2 := t.AmountAll(env, 1, "2")
+		k := float32(am1 + am2)
 
-		if am1 > sm.sureness || am2 > sm.sureness {
-			if am1 > am2 {
-				if sm.color == 2 {
-					sm.sureness--
-				} else {
-					sm.sureness++
-				}
-				if sm.sureness == 0 {
-					sm.color = 1
-				}
-			} else if am2 > am1 {
-				if sm.color == 1 {
-					sm.sureness--
-				} else {
-					sm.sureness++
-				}
-				if sm.sureness == 0 {
-					sm.color = 2
-				}
+			if am1 > k*float32(*alpha) &&  am1 > am2 {
+				sm.colourCounts[0]++
+			} else if am2 > k*0.5 && am2 > am1 {
+				sm.colourCounts[1]++
 			}
+
+		sm.sureness++
+
+		if sm.colourCounts[sm.color] < sm.colourCounts[(sm.color+1)%2] {
+			sm.color = (sm.color+1) %2
+			sm.sureness = 0
 		}
 
+		// Add a vote for our new colour if we are sure
 		if sm.sureness > 1 {
-			t.Drop(env, 1, strconv.Itoa(sm.color))
+			t.Drop(env, 1, strconv.Itoa(sm.color+1))
 		}
 
 		t.Step(env)
@@ -106,7 +104,7 @@ func main() {
 	experiment.InitPheromone("1", color.RGBA{0x00, 0xFF, 0x00, 0x00})
 	experiment.InitPheromone("2", color.RGBA{0xFF, 0x00, 0xFF, 0x00})
 	experiment.InitPheromone("3", color.RGBA{0xFF, 0x00, 0x00, 0x00})
-
+	fmt.Printf("Step, Votes for 1, Votes for 2\n")
 	experiment.OnStep = func(env *core.Environment, turtles []*core.Turtle, step int) {
 		num1 := 0
 		num2 := 0
@@ -117,7 +115,7 @@ func main() {
 
 		for _, turtle := range turtles {
 			agent := turtle.GetActor().(*Snowball)
-			if agent.GetColor() == 1 {
+			if agent.GetColor() == 0 {
 				num1++
 			} else {
 				num2++