Implement Crossbows

server/entity/firework.go

@@ -11,13 +11,15 @@ import (
 // for creating decorative explosions, boosting when flying with elytra, and
 // loading into a crossbow as ammunition.
 func NewFirework(opts world.EntitySpawnOpts, firework item.Firework) *world.EntityHandle {
-	return NewFireworkAttached(opts, firework, nil, false)
+	return NewFireworkAttached(opts, firework, nil, 1.15, 0.04, false)
 }
 
 // NewFireworkAttached creates a firework entity with an owner that the firework
 // may be attached to.
-func NewFireworkAttached(opts world.EntitySpawnOpts, firework item.Firework, owner world.Entity, attached bool) *world.EntityHandle {
+func NewFireworkAttached(opts world.EntitySpawnOpts, firework item.Firework, owner world.Entity, sidewaysVelocityMultiplier, upwardsAcceleration float64, attached bool) *world.EntityHandle {
 	conf := fireworkConf
+	conf.SidewaysVelocityMultiplier = sidewaysVelocityMultiplier
+	conf.UpwardsAcceleration = upwardsAcceleration
 	conf.Firework = firework
 	conf.ExistenceDuration = firework.RandomisedDuration()
 	conf.Attached = attached
@@ -27,10 +29,7 @@ func NewFireworkAttached(opts world.EntitySpawnOpts, firework item.Firework, own
 	return opts.New(FireworkType, conf)
 }
 
-var fireworkConf = FireworkBehaviourConfig{
-	SidewaysVelocityMultiplier: 1.15,
-	UpwardsAcceleration:        0.04,
-}
+var fireworkConf = FireworkBehaviourConfig{}
 
 // FireworkType is a world.EntityType implementation for Firework.
 var FireworkType fireworkType

server/entity/register.go

@@ -35,8 +35,8 @@ var conf = world.EntityRegistryConfig{
 	EnderPearl:         NewEnderPearl,
 	FallingBlock:       NewFallingBlock,
 	Lightning:          NewLightning,
-	Firework: func(opts world.EntitySpawnOpts, firework world.Item, owner world.Entity, attached bool) *world.EntityHandle {
-		return NewFireworkAttached(opts, firework.(item.Firework), owner, attached)
+	Firework: func(opts world.EntitySpawnOpts, firework world.Item, owner world.Entity, sidewaysVelocityMultiplier, upwardsAcceleration float64, attached bool) *world.EntityHandle {
+		return NewFireworkAttached(opts, firework.(item.Firework), owner, sidewaysVelocityMultiplier, upwardsAcceleration, attached)
 	},
 	Item: func(opts world.EntitySpawnOpts, it any) *world.EntityHandle {
 		return NewItem(opts, it.(item.Stack))

server/item/crossbow.go

@@ -0,0 +1,204 @@
+package item
+
+import (
+	"time"
+	_ "unsafe"
+
+	"github.com/df-mc/dragonfly/server/world"
+	"github.com/df-mc/dragonfly/server/world/sound"
+)
+
+// Crossbow is a ranged weapon similar to a bow that uses arrows or fireworks as ammunition.
+type Crossbow struct {
+	// Item is the item the crossbow is charged with.
+	Item Stack
+}
+
+// Charge starts the charging process and checks if the charge duration meets the required duration.
+func (c Crossbow) Charge(releaser Releaser, tx *world.Tx, ctx *UseContext, duration time.Duration) bool {
+	if !c.Item.Empty() {
+		return false
+	}
+
+	creative := releaser.GameMode().CreativeInventory()
+	held, left := releaser.HeldItems()
+
+	//TODO: modify chargeDuration to prevent funky loading
+	chargeDuration := time.Duration(1.25 * float64(time.Second))
+	for _, enchant := range held.Enchantments() {
+		if q, ok := enchant.Type().(interface{ ChargeDuration(int) time.Duration }); ok {
+			chargeDuration = min(chargeDuration, q.ChargeDuration(enchant.Level()))
+		}
+	}
+
+	if duration < chargeDuration {
+		return false
+	}
+
+	var projectileItem Stack
+	if !left.Empty() {
+		_, isFirework := left.Item().(Firework)
+		_, isArrow := left.Item().(Arrow)
+		if isFirework || isArrow {
+			projectileItem = left
+		}
+	}
+
+	if projectileItem.Empty() {
+		var ok bool
+		projectileItem, ok = ctx.FirstFunc(func(stack Stack) bool {
+			_, isArrow := stack.Item().(Arrow)
+			return isArrow
+		})
+
+		if !ok && !creative {
+			return false
+		}
+
+		if projectileItem.Empty() {
+			projectileItem = NewStack(Arrow{}, 1)
+		}
+	}
+
+	c.Item = projectileItem.Grow(-projectileItem.Count() + 1)
+	if !creative {
+		ctx.Consume(c.Item)
+	}
+
+	crossbow := held.WithItem(c)
+	releaser.SetHeldItems(crossbow, left)
+	return true
+}
+
+// ContinueCharge ...
+func (c Crossbow) ContinueCharge(releaser Releaser, tx *world.Tx, duration time.Duration) {
+	if !c.Item.Empty() {
+		return
+	}
+
+	//TODO: check if the releaser has required items in inventory.
+	// currently it will send the sound regardless if charging or not.
+
+	held, _ := releaser.HeldItems()
+	chargeDuration, quickChargeLevel := time.Duration(1.25*float64(time.Second)), 0
+	for _, enchant := range held.Enchantments() {
+		if q, ok := enchant.Type().(interface{ ChargeDuration(int) time.Duration }); ok {
+			chargeDuration = min(chargeDuration, q.ChargeDuration(enchant.Level()))
+			quickChargeLevel = enchant.Level()
+		}
+	}
+
+	progress := float64(duration) / float64(chargeDuration)
+	if duration.Seconds() <= 0.1 {
+		if quickChargeLevel > 0 {
+			tx.PlaySound(releaser.Position(), sound.CrossbowQuickChargeLoadingStart{})
+		} else {
+			tx.PlaySound(releaser.Position(), sound.CrossbowLoadingStart{})
+		}
+	}
+
+	ticks := duration.Milliseconds() / 50
+	if ticks%16 == 0 { // After 16 ticks play the middle charge sound
+		if quickChargeLevel > 0 {
+			tx.PlaySound(releaser.Position(), sound.CrossbowQuickChargeLoadingMiddle{})
+		} else {
+			tx.PlaySound(releaser.Position(), sound.CrossbowLoadingMiddle{})
+		}
+	}
+
+	if progress >= 1 && quickChargeLevel > 0 {
+		tx.PlaySound(releaser.Position(), sound.CrossbowQuickChargeEnd{})
+	}
+}
+
+// ReleaseCharge checks if the item is fully charged and, if so, releases it.
+func (c Crossbow) ReleaseCharge(releaser Releaser, tx *world.Tx, ctx *UseContext) bool {
+	if c.Item.Empty() {
+		return false
+	}
+
+	creative := releaser.GameMode().CreativeInventory()
+	rot := releaser.Rotation().Neg()
+	dirVec := releaser.Rotation().Vec3().Normalize()
+
+	if firework, isFirework := c.Item.Item().(Firework); isFirework {
+		createFirework := tx.World().EntityRegistry().Config().Firework
+		fireworkEntity := createFirework(world.EntitySpawnOpts{
+			Position: torsoPosition(releaser),
+			Velocity: dirVec.Mul(0.1),
+			Rotation: rot,
+		}, firework, releaser, 1.15, 0, false)
+		tx.AddEntity(fireworkEntity)
+		ctx.DamageItem(3)
+	} else {
+		createArrow := tx.World().EntityRegistry().Config().Arrow
+		arrow := createArrow(world.EntitySpawnOpts{
+			Position: torsoPosition(releaser),
+			Velocity: dirVec.Mul(5.15),
+			Rotation: rot,
+		}, 9, releaser, false, false, !creative, 0, c.Item.Item().(Arrow).Tip)
+		tx.AddEntity(arrow)
+		ctx.DamageItem(1)
+	}
+
+	c.Item = Stack{}
+	held, left := releaser.HeldItems()
+	crossbow := held.WithItem(c)
+	releaser.SetHeldItems(crossbow, left)
+	tx.PlaySound(releaser.Position(), sound.CrossbowShoot{})
+	return true
+}
+
+// MaxCount always returns 1.
+func (Crossbow) MaxCount() int {
+	return 1
+}
+
+// DurabilityInfo ...
+func (Crossbow) DurabilityInfo() DurabilityInfo {
+	return DurabilityInfo{
+		MaxDurability: 464,
+		BrokenItem:    simpleItem(Stack{}),
+	}
+}
+
+// FuelInfo ...
+func (Crossbow) FuelInfo() FuelInfo {
+	return newFuelInfo(time.Second * 15)
+}
+
+// EnchantmentValue ...
+func (Crossbow) EnchantmentValue() int {
+	return 1
+}
+
+// EncodeItem ...
+func (Crossbow) EncodeItem() (name string, meta int16) {
+	return "minecraft:crossbow", 0
+}
+
+// DecodeNBT ...
+func (c Crossbow) DecodeNBT(data map[string]any) any {
+	c.Item = mapItem(data, "chargedItem")
+	return c
+}
+
+// EncodeNBT ...
+func (c Crossbow) EncodeNBT() map[string]any {
+	if !c.Item.Empty() {
+		return map[string]any{
+			"chargedItem": writeItem(c.Item, true),
+		}
+	}
+	return nil
+}
+
+// noinspection ALL
+//
+//go:linkname writeItem github.com/df-mc/dragonfly/server/internal/nbtconv.WriteItem
+func writeItem(s Stack, disk bool) map[string]any
+
+// noinspection ALL
+//
+//go:linkname mapItem github.com/df-mc/dragonfly/server/internal/nbtconv.MapItem
+func mapItem(x map[string]any, k string) Stack

server/item/enchantment/quick_charge.go

@@ -0,0 +1,49 @@
+package enchantment
+
+import (
+	"github.com/df-mc/dragonfly/server/item"
+	"github.com/df-mc/dragonfly/server/world"
+	"time"
+)
+
+// QuickCharge is an enchantment for quickly reloading a crossbow.
+var QuickCharge quickCharge
+
+type quickCharge struct{}
+
+// Name ...
+func (quickCharge) Name() string {
+	return "Quick Charge"
+}
+
+// MaxLevel ...
+func (quickCharge) MaxLevel() int {
+	return 3
+}
+
+// Cost ...
+func (quickCharge) Cost(level int) (int, int) {
+	minCost := 12 + (level-1)*20
+	return minCost, 50
+}
+
+// Rarity ...
+func (quickCharge) Rarity() item.EnchantmentRarity {
+	return item.EnchantmentRarityUncommon
+}
+
+// ChargeDuration returns the charge duration.
+func (quickCharge) ChargeDuration(level int) time.Duration {
+	return time.Duration((1.25 - 0.25*float64(level)) * float64(time.Second))
+}
+
+// CompatibleWithEnchantment ...
+func (quickCharge) CompatibleWithEnchantment(item.EnchantmentType) bool {
+	return true
+}
+
+// CompatibleWithItem ...
+func (quickCharge) CompatibleWithItem(i world.Item) bool {
+	_, ok := i.(item.Crossbow)
+	return ok
+}

server/item/enchantment/register.go

@@ -38,7 +38,7 @@ func init() {
 	// TODO: (32) Channeling.
 	// TODO: (33) Multishot.
 	// TODO: (34) Piercing.
-	// TODO: (35) Quick Charge.
+	item.RegisterEnchantment(35, QuickCharge)
 	item.RegisterEnchantment(36, SoulSpeed)
 	item.RegisterEnchantment(37, SwiftSneak)
 }

server/item/firework.go

@@ -31,7 +31,7 @@ func (f Firework) Use(tx *world.Tx, user User, ctx *UseContext) bool {
 	tx.PlaySound(pos, sound.FireworkLaunch{})
 	create := tx.World().EntityRegistry().Config().Firework
 	opts := world.EntitySpawnOpts{Position: pos, Rotation: user.Rotation()}
-	tx.AddEntity(create(opts, f, user, true))
+	tx.AddEntity(create(opts, f, user, 1.15, 0.04, true))
 
 	ctx.SubtractFromCount(1)
 	return true
@@ -42,7 +42,7 @@ func (f Firework) UseOnBlock(pos cube.Pos, _ cube.Face, clickPos mgl64.Vec3, tx
 	fpos := pos.Vec3().Add(clickPos)
 	create := tx.World().EntityRegistry().Config().Firework
 	opts := world.EntitySpawnOpts{Position: fpos, Rotation: cube.Rotation{rand.Float64() * 360, 90}}
-	tx.AddEntity(create(opts, f, user, false))
+	tx.AddEntity(create(opts, f, user, 1.15, 0.04, false))
 	tx.PlaySound(fpos, sound.FireworkLaunch{})
 
 	ctx.SubtractFromCount(1)

server/item/item.go

@@ -155,6 +155,16 @@ type Releasable interface {
 	Requirements() []Stack
 }
 
+// Chargeable represents an item that can be charged.
+type Chargeable interface {
+	// Charge is called when an item is being used.
+	Charge(releaser Releaser, tx *world.Tx, ctx *UseContext, duration time.Duration) bool
+	// ContinueCharge continues the charge.
+	ContinueCharge(releaser Releaser, tx *world.Tx, duration time.Duration)
+	// ReleaseCharge is called when an item is being released.
+	ReleaseCharge(releaser Releaser, tx *world.Tx, ctx *UseContext) bool
+}
+
 // User represents an entity that is able to use an item in the world, typically entities such as players,
 // which interact with the world using an item.
 type User interface {
@@ -217,6 +227,16 @@ func eyePosition(e world.Entity) mgl64.Vec3 {
 	return pos
 }
 
+// torsoPosition returns the position of the torso of the entity if the entity implements entity.Torsoed, or the
+// actual position if it doesn't.
+func torsoPosition(e world.Entity) mgl64.Vec3 {
+	pos := e.Position()
+	if torso, ok := e.(interface{ TorsoHeight() float64 }); ok {
+		pos = pos.Add(mgl64.Vec3{0, torso.TorsoHeight()})
+	}
+	return pos
+}
+
 // Int32FromRGBA converts a color.RGBA into an int32. These int32s are present in things such as signs and dyed leather armour.
 func int32FromRGBA(x color.RGBA) int32 {
 	if x.R == 0 && x.G == 0 && x.B == 0 {

server/item/register.go

@@ -40,6 +40,7 @@ func init() {
 	world.RegisterItem(Compass{})
 	world.RegisterItem(Cookie{})
 	world.RegisterItem(CopperIngot{})
+	world.RegisterItem(Crossbow{})
 	world.RegisterItem(Diamond{})
 	world.RegisterItem(DiscFragment{})
 	world.RegisterItem(DragonBreath{})