support setting heading in instructions

player.go

@@ -69,6 +69,9 @@ func (p *player) recv() {
 				if msg.MoveTo != nil {
 					r.MoveTo = msg.MoveTo
 				}
+				if msg.Heading != nil {
+					r.DesiredHeading = msg.Heading
+				}
 				if msg.FireAt != nil {
 					r.FireAt = msg.FireAt
 				}

protocol.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	v "bitbucket.org/hackerbots/vector"
 	"code.google.com/p/go.net/websocket"
 	"log"
 )
@@ -203,6 +204,7 @@ func addPlayer(ws *websocket.Conn) {
 				Id:       idg.Hash(),
 				Name:     name,
 				Health:   10,
+				Heading:  v.Vector2d{1, 0},
 				Scanners: make([]Scanner, 0)}
 			r.Health = r.Stats.Hp
 			log.Printf("Adding Robot: %v", r)

robot.go

@@ -20,6 +20,7 @@ type Robot struct {
 	ActiveScan     bool        `json:"-"`
 	Position       v.Point2d   `json:"position"`
 	Heading        v.Vector2d  `json:"heading"`
+	DesiredHeading *v.Vector2d `json:"-"`
 	MoveTo         *v.Point2d  `json:"-"`
 	FireAt         *v.Point2d  `json:"-"`
 	Scanners       []Scanner   `json:"scanners"`
@@ -155,6 +156,7 @@ func DeriveStats(request StatsRequest) Stats {
 type Instruction struct {
 	Message     *string     `json:"message,omitempty"`
 	MoveTo      *v.Point2d  `json:"move_to,omitempty"`
+	Heading     *v.Vector2d `json:"heading,omitempty"`
 	FireAt      *v.Point2d  `json:"fire_at,omitempty"`
 	Probe       *v.Point2d  `json:"probe,omitempty"`
 	TargetSpeed *float32    `json:"target_speed,omitempty"`
@@ -229,6 +231,11 @@ func (r *Robot) Tick(g *game) {
 		new_heading = r.MoveTo.Sub(r.Position).Normalize()
 	}
 
+	if r.DesiredHeading != nil {
+		// Where do we WANT to be heading?
+		new_heading = r.DesiredHeading.Normalize()
+	}
+
 	if new_heading.Mag() > 0 {
 		// Is our direction change too much? Hard coding to 5 degrees/s for now
 		angle := v.Angle(current_heading, new_heading) * v.Rad2deg