Added weapon system. Animated laser.

weapons/holster.go

@@ -0,0 +1,51 @@
+package weapons
+
+import "mover/gamedata"
+
+type Holster struct {
+	activewp gamedata.WeaponType
+	guns     map[gamedata.WeaponType]Weapon
+}
+
+func NewHolster() *Holster {
+	holster := &Holster{
+		guns:     make(map[gamedata.WeaponType]Weapon),
+		activewp: gamedata.WeaponTypeGun,
+	}
+	holster.AddWeapon(NewGun())
+	holster.AddWeapon(NewLaser())
+	return holster
+}
+
+func (h *Holster) GetActiveWeapon() Weapon {
+	return h.guns[h.activewp]
+}
+
+func (h *Holster) GetActiveWeaponType() gamedata.WeaponType {
+	return h.guns[h.activewp].GetWeaponType()
+}
+
+func (h *Holster) AddWeapon(w Weapon) {
+	_, ok := h.guns[w.GetWeaponType()]
+	if !ok {
+		h.guns[w.GetWeaponType()] = w
+	}
+}
+
+func (h *Holster) CycleWeapon() {
+	//no weapons, nothing to do
+	if len(h.guns) == 0 {
+		return
+	}
+
+	//keep searching until we find the next weapon that exists
+	for ok := false; !ok; {
+		nextwp := (h.activewp + 1) % gamedata.WeaponTypeMax
+		_, ok = h.guns[nextwp]
+		if ok {
+			h.activewp = nextwp
+		}
+
+	}
+
+}