diff --git a/actors/slush.go b/actors/slush.go
index da0adb4..598eb6b 100644
--- a/actors/slush.go
+++ b/actors/slush.go
@@ -12,14 +12,26 @@ type Slush struct {
 
 func (sm *Slush) Setup(env *core.Environment, t *core.Turtle) {
 	sm.color = rand.Intn(2) + 1
+	if sm.color !=1 && sm.color !=2 {
+		panic("wrong color")
+	}
 }
 
 func (sm *Slush) Run(env *core.Environment, t *core.Turtle) {
 	t.Wiggle()
-	if t.Near(env, 1,2, "1") {
-		sm.color = 1
-	} else if t.Near(env, 1,2, "2") {
-		sm.color = 2
+	notChanged := true
+	threshold := float32(1.0)
+	for notChanged {
+		notChanged = false
+		if t.Near(env, 1, threshold, "1") {
+			sm.color = 1
+			notChanged = true
+		}
+		if t.Near(env, 1, threshold, "2") {
+			sm.color = 2
+			notChanged = true
+		}
+		threshold+=0.01
 	}
 	t.Step(env)
 	t.Drop(env, 1, strconv.Itoa(sm.color))
diff --git a/actors/snowball.go b/actors/snowball.go
new file mode 100644
index 0000000..8ca0889
--- /dev/null
+++ b/actors/snowball.go
@@ -0,0 +1,40 @@
+package actors
+
+import (
+	"git.openprivacy.ca/sarah/microworlds/core"
+	"math/rand"
+	"strconv"
+)
+
+type Snowball struct {
+	color int
+	sureness int
+}
+
+func (sm *Snowball) Setup(env *core.Environment, t *core.Turtle) {
+	sm.color = rand.Intn(2) + 1
+	if sm.color !=1 && sm.color !=2 {
+		panic("wrong color")
+	}
+	sm.sureness = 0
+}
+
+func (sm *Snowball) Run(env *core.Environment, t *core.Turtle) {
+	t.Wiggle()
+	if sm.color == 1 && t.Near(env, 1, float32(sm.sureness), "1") {
+		sm.sureness++
+	} else if sm.color == 1 && t.Near(env, 1, float32(sm.sureness), "2") {
+		sm.sureness = 0
+		sm.color = 2
+	} else if sm.color == 2 && t.Near(env, 1, float32(sm.sureness), "2") {
+		sm.sureness++
+	} else if sm.color == 2 && t.Near(env, 1, float32(sm.sureness), "1") {
+		sm.sureness = 0
+		sm.color = 1
+	}
+	t.Step(env)
+	t.Drop(env, 1, strconv.Itoa(sm.color))
+}
+
+
+
diff --git a/graphics/graphics.go b/graphics/graphics.go
index 16884fc..590f36c 100644
--- a/graphics/graphics.go
+++ b/graphics/graphics.go
@@ -64,8 +64,11 @@ func (g *Graphics) Render(env *core.Environment, turtles []*core.Turtle) {
 			for name, color := range g.colorMap {
 				amount := math.Min(float64(env.Sniff(name, x, y)), 255)
 
+				if amount > 2 {
+					amount  = 2
+				}
+
 				if amount > 0 {
-					// TODO explictly define this scale
 					scaledamountRed := uint8(float64(color[0])  * (amount/2))
 					scaledamountGreen := uint8(float64(color[1])  * (amount/2))
 					scaledamountBlue := uint8(float64(color[2])  * (amount/2))
@@ -76,7 +79,7 @@ func (g *Graphics) Render(env *core.Environment, turtles []*core.Turtle) {
 			}
 
 			g.renderer.SetDrawColor(uint8(scaledamountRedTotal/len(g.colorMap)),uint8(scaledamountGreenTotal/len(g.colorMap)),uint8(scaledamountBlueTotal/len(g.colorMap)), uint8(0xF0))
-			g.renderer.DrawPoint(int32(x), int32(y))
+			g.DrawTileColor(int32(x), int32(y))
 
 			if env.HasValue(x, y) {
 				g.renderer.SetDrawColor(255, 255, 255, uint8(255))
diff --git a/main.go b/main.go
index 86533a3..4fc501c 100644
--- a/main.go
+++ b/main.go
@@ -97,8 +97,16 @@ func main() {
 		}
 		env.InitPheromone("1")
 		env.InitPheromone("2")
-		g.ColorPheromone("1", [4]uint8{0x00, 0xFF, 0x00, 0x00})
-		g.ColorPheromone("2", [4]uint8{0x00, 0, 0xFF, 0x00})
+		g.ColorPheromone("1", [4]uint8{0x80, 0xFF, 0x00, 0x00})
+		g.ColorPheromone("2", [4]uint8{0xFF, 0, 0xFF, 0x00})
+	case "snowball":
+		for i := 0; i < *numTurtles; i++ {
+			turtles[i] = core.NewTurtle(env, &actors.Snowball{})
+		}
+		env.InitPheromone("1")
+		env.InitPheromone("2")
+		g.ColorPheromone("1", [4]uint8{0x00, 0xFF, 0xFF, 0x00})
+		g.ColorPheromone("2", [4]uint8{0xFF, 0xFF, 0x00, 0x00})
 	case "flocking":
 		for i := 0; i < *numTurtles; i++ {
 			turtles[i] = core.NewTurtle(env, &actors.Flocking{SniffDistance: 1})