Remove special case wall collisions, replace with generated objects

obstacle.go

@@ -49,24 +49,41 @@ func (o Obstacle) distance_from_point(p v.Point2d) float64 {
 	return dist
 }
 
+func obstacleFromValues(x, y, w, h float64, hp int) (o Obstacle) {
+	return Obstacle{
+		Bounds: v.AABB2d{
+			A: v.Point2d{X: x, Y: y},
+			B: v.Point2d{X: x + w, Y: y + h},
+		},
+		Hp: hp,
+	}
+}
+
 // GenerateObstacles returns a slice of (count) obstacles within a region
 // bounded by width, height.
 func GenerateObstacles(count int, width, height float64) []Obstacle {
 	out := []Obstacle{}
+
+	// Create obstacles that cover the edges of the world, so we don't need to
+	// special case collision at the edges
+	// left wall
+	out = append(out, obstacleFromValues(0, 5, 5, height-10, 0))
+	// // right wall
+	out = append(out, obstacleFromValues(width-5, 5, 5, height-10, 0))
+	// // top wall
+	out = append(out, obstacleFromValues(0, height-5, width, 5, 0))
+	// bottom wall
+	out = append(out, obstacleFromValues(0, 0, width, 5, 0))
+
+	// Now create N random objects somewhere in the world
 	for i := 0; i < count; i++ {
 		x := rand.Float64() * (width - (width / 10))
 		y := rand.Float64() * (height - (height / 10))
-		w := rand.Float64() * (width / 10)
-		h := rand.Float64() * (height / 10)
+		w := rand.Float64()*(width/10) + 20
+		h := rand.Float64()*(height/10) + 20
 		out = append(
 			out,
-			Obstacle{
-				Bounds: v.AABB2d{
-					A: v.Point2d{X: x, Y: y},
-					B: v.Point2d{X: 20 + x + w, Y: 20 + y + h},
-				},
-				Hp: 10000,
-			})
+			obstacleFromValues(x, y, w, h, 10000))
 	}
 	return out
 }