feat: Move along grid

1 files changed, 36 insertions, 6 deletions

diff --git a/move.go b/move.go
index f2cee2b..97d4809 100644
--- a/move.go
+++ b/move.go
@@ -1,19 +1,49 @@
 package main
 
+import (
+	"math"
+)
+
 type Move struct {
 	IsActive    bool
+	Origin      Point
 	Destination Point
+	Nodes       []Point
+}
+
+func NewMove(origin Point, destination Point) Move {
+	nodes := []Point{}
+	current := Point{
+		origin.X/100*100 + 50,
+		origin.Y/100*100 + 50,
+	}
+	for current != destination {
+		next := current
+		if math.Abs(float64(destination.X-current.X)) > math.Abs(float64(destination.Y-current.Y)) {
+			next.X = current.X + int(math.Copysign(100, float64(destination.X-current.X)))
+		} else {
+			next.Y = current.Y + int(math.Copysign(100, float64(destination.Y-current.Y)))
+		}
+		nodes = append(nodes, next)
+		current = next
+	}
+	return Move{IsActive: true, Origin: origin, Destination: destination, Nodes: nodes}
 }
 
 func (m *Move) Update(position Point, speed int) Point {
 	if !m.IsActive {
 		return position
 	}
-	remainingMove := m.Destination.Sub(position)
-	delta := remainingMove.Mul(speed).Div(int(Length(remainingMove)))
-	next := position.Add(delta)
-	if Distance(next, m.Destination) < float64(speed) {
-		m.IsActive = false
+	next := m.Nodes[0]
+	if Distance(position, next) < float64(speed) {
+		if next == m.Destination {
+			m.IsActive = false
+		} else {
+			m.Nodes = m.Nodes[1:]
+		}
+		return next
 	}
-	return next
+	remainingMove := next.Sub(position)
+	delta := remainingMove.Mul(speed).Div(int(Length(remainingMove)))
+	return position.Add(delta)
 }