server/item: Implemented fireworks and firework stars (#576)

server/entity/action.go

@@ -41,6 +41,9 @@ type PickedUpAction struct {
 	action
 }
 
+// FireworkExplosionAction is a world.EntityAction that makes a Firework rocket display an explosion particle.
+type FireworkExplosionAction struct{ action }
+
 // action implements the Action interface. Structures in this package may embed it to gets its functionality
 // out of the box.
 type action struct{}

server/entity/firework.go

@@ -0,0 +1,181 @@
+package entity
+
+import (
+	"github.com/df-mc/dragonfly/server/block/cube"
+	"github.com/df-mc/dragonfly/server/block/cube/trace"
+	"github.com/df-mc/dragonfly/server/entity/damage"
+	"github.com/df-mc/dragonfly/server/internal/nbtconv"
+	"github.com/df-mc/dragonfly/server/item"
+	"github.com/df-mc/dragonfly/server/world"
+	"github.com/df-mc/dragonfly/server/world/sound"
+	"github.com/go-gl/mathgl/mgl64"
+	"math"
+	"math/rand"
+)
+
+// Firework is an item (and entity) used for creating decorative explosions, boosting when flying with elytra, and
+// loading into a crossbow as ammunition.
+type Firework struct {
+	transform
+
+	yaw, pitch float64
+	firework   item.Firework
+
+	owner world.Entity
+
+	c *MovementComputer
+
+	ticks int
+	close bool
+}
+
+// NewFirework ...
+func NewFirework(pos mgl64.Vec3, yaw, pitch float64, firework item.Firework) *Firework {
+	f := &Firework{
+		yaw:      yaw,
+		pitch:    pitch,
+		firework: firework,
+		c:        &MovementComputer{},
+		ticks:    int(firework.RandomisedDuration().Milliseconds() / 50),
+	}
+	f.transform = newTransform(f, pos)
+	f.vel = mgl64.Vec3{rand.Float64() * 0.001, 0.05, rand.Float64() * 0.001}
+	return f
+}
+
+// Name ...
+func (f *Firework) Name() string {
+	return "Firework Rocket"
+}
+
+// EncodeEntity ...
+func (f *Firework) EncodeEntity() string {
+	return "minecraft:fireworks_rocket"
+}
+
+// BBox ...
+func (f *Firework) BBox() cube.BBox {
+	return cube.BBox{}
+}
+
+// Firework returns the underlying item.Firework of the Firework.
+func (f *Firework) Firework() item.Firework {
+	return f.firework
+}
+
+// Rotation ...
+func (f *Firework) Rotation() (float64, float64) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	return f.yaw, f.pitch
+}
+
+// Tick ...
+func (f *Firework) Tick(w *world.World, current int64) {
+	if f.close {
+		_ = f.Close()
+		return
+	}
+
+	f.mu.Lock()
+	f.vel[0] *= 1.15
+	f.vel[1] += 0.04
+	f.vel[2] *= 1.15
+	m := f.c.TickMovement(f, f.pos, f.vel, f.yaw, f.pitch)
+	f.pos, f.vel, f.yaw, f.pitch = m.pos, m.vel, m.yaw, m.pitch
+	f.mu.Unlock()
+
+	m.Send()
+
+	if m.pos[1] < float64(w.Range()[0]) && current%10 == 0 {
+		f.close = true
+		return
+	}
+
+	f.ticks--
+	if f.ticks >= 0 {
+		return
+	}
+
+	explosions := f.Firework().Explosions
+	for _, v := range w.Viewers(m.pos) {
+		v.ViewEntityAction(f, FireworkExplosionAction{})
+	}
+	for _, explosion := range explosions {
+		if explosion.Shape == item.FireworkShapeHugeSphere() {
+			w.PlaySound(m.pos, sound.FireworkHugeBlast{})
+		} else {
+			w.PlaySound(m.pos, sound.FireworkBlast{})
+		}
+		if explosion.Twinkle {
+			w.PlaySound(m.pos, sound.FireworkTwinkle{})
+		}
+	}
+
+	if len(explosions) > 0 {
+		force := float64(len(explosions)*2) + 5.0
+		for _, e := range w.EntitiesWithin(f.BBox().Translate(m.pos).Grow(5.25), func(e world.Entity) bool {
+			l, living := e.(Living)
+			return !living || l.AttackImmune()
+		}) {
+			pos := e.Position()
+			dist := m.pos.Sub(pos).Len()
+			if dist > 5.0 {
+				// The maximum distance allowed is 5.0 blocks.
+				continue
+			}
+			if _, ok := trace.Perform(m.pos, pos, w, e.BBox().Grow(0.3), func(world.Entity) bool {
+				return true
+			}); ok {
+				dmg := force * math.Sqrt((5.0-dist)/5.0)
+				e.(Living).Hurt(dmg, damage.SourceProjectile{Owner: f.Owner(), Projectile: f})
+			}
+		}
+	}
+
+	f.close = true
+}
+
+// New creates an firework with the position, velocity, yaw, and pitch provided. It doesn't spawn the firework,
+// only returns it.
+func (f *Firework) New(pos mgl64.Vec3, yaw, pitch float64, firework item.Firework) world.Entity {
+	return NewFirework(pos, yaw, pitch, firework)
+}
+
+// Owner ...
+func (f *Firework) Owner() world.Entity {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	return f.owner
+}
+
+// Own ...
+func (f *Firework) Own(owner world.Entity) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.owner = owner
+}
+
+// DecodeNBT decodes the properties in a map to a Firework and returns a new Firework entity.
+func (f *Firework) DecodeNBT(data map[string]any) any {
+	firework := NewFirework(
+		nbtconv.MapVec3(data, "Pos"),
+		float64(nbtconv.Map[float32](data, "Pitch")),
+		float64(nbtconv.Map[float32](data, "Yaw")),
+		nbtconv.MapItem(data, "Item").Item().(item.Firework),
+	)
+	firework.vel = nbtconv.MapVec3(data, "Motion")
+	return firework
+}
+
+// EncodeNBT encodes the Firework entity's properties as a map and returns it.
+func (f *Firework) EncodeNBT() map[string]any {
+	yaw, pitch := f.Rotation()
+	return map[string]any{
+		"Item":   nbtconv.WriteItem(item.NewStack(f.Firework(), 1), true),
+		"Pos":    nbtconv.Vec3ToFloat32Slice(f.Position()),
+		"Motion": nbtconv.Vec3ToFloat32Slice(f.Velocity()),
+		"Yaw":    yaw,
+		"Pitch":  pitch,
+	}
+}

server/entity/register.go

@@ -14,4 +14,5 @@ func init() {
 	world.RegisterEntity(&Lightning{})
 	world.RegisterEntity(&Arrow{})
 	world.RegisterEntity(&ExperienceOrb{})
+	world.RegisterEntity(&Firework{})
 }

server/item/colour.go

@@ -182,3 +182,13 @@ func (c colour) String() string {
 func (c colour) Uint8() uint8 {
 	return uint8(c)
 }
+
+// invertColour converts the item.Colour passed and returns the colour ID inverted.
+func invertColour(c Colour) int16 {
+	return ^int16(c.Uint8()) & 0xf
+}
+
+// invertColourID converts the int16 passed the returns the item.Colour inverted.
+func invertColourID(id int16) Colour {
+	return Colours()[uint8(^id&0xf)]
+}

server/item/dye.go

@@ -31,15 +31,6 @@ type dyeable interface {
 	Dye(c Colour) (world.Block, bool)
 }
 
-// AllDyes returns all 16 dye items
-func AllDyes() []world.Item {
-	b := make([]world.Item, 0, 16)
-	for _, c := range Colours() {
-		b = append(b, Dye{Colour: c})
-	}
-	return b
-}
-
 // EncodeItem ...
 func (d Dye) EncodeItem() (name string, meta int16) {
 	if d.Colour.String() == "silver" {

server/item/ender_pearl.go

@@ -33,9 +33,7 @@ func (e EnderPearl) Use(w *world.World, user User, ctx *UseContext) bool {
 	ctx.SubtractFromCount(1)
 
 	w.PlaySound(user.Position(), sound.ItemThrow{})
-
 	w.AddEntity(entity)
-
 	return true
 }
 

server/item/firework.go

@@ -0,0 +1,86 @@
+package item
+
+import (
+	"github.com/df-mc/dragonfly/server/block/cube"
+	"github.com/df-mc/dragonfly/server/world"
+	"github.com/df-mc/dragonfly/server/world/sound"
+	"github.com/go-gl/mathgl/mgl64"
+	"math/rand"
+	"time"
+)
+
+// Firework is an item (and entity) used for creating decorative explosions, boosting when flying with elytra, and
+// loading into a crossbow as ammunition.
+type Firework struct {
+	// Duration is the flight duration of the firework.
+	Duration time.Duration
+	// Explosions is the list of explosions the firework should create when launched.
+	Explosions []FireworkExplosion
+}
+
+// UseOnBlock ...
+func (f Firework) UseOnBlock(blockPos cube.Pos, _ cube.Face, clickPos mgl64.Vec3, w *world.World, user User, ctx *UseContext) bool {
+	firework, ok := world.EntityByName("minecraft:fireworks_rocket")
+	if !ok {
+		return false
+	}
+
+	p, ok := firework.(interface {
+		New(pos mgl64.Vec3, yaw, pitch float64, firework Firework) world.Entity
+	})
+	if !ok {
+		return false
+	}
+
+	pos := blockPos.Vec3().Add(clickPos)
+	entity := p.New(pos, rand.Float64()*360, 90, f)
+	if o, ok := entity.(owned); ok {
+		o.Own(user)
+	}
+
+	ctx.SubtractFromCount(1)
+
+	w.PlaySound(pos, sound.FireworkLaunch{})
+	w.AddEntity(entity)
+	return true
+}
+
+// EncodeNBT ...
+func (f Firework) EncodeNBT() map[string]any {
+	explosions := make([]any, 0, len(f.Explosions))
+	for _, explosion := range f.Explosions {
+		explosions = append(explosions, explosion.EncodeNBT())
+	}
+	return map[string]any{"Fireworks": map[string]any{
+		"Explosions": explosions,
+		"Flight":     uint8(f.Duration.Milliseconds() / 50),
+	}}
+}
+
+// DecodeNBT ...
+func (f Firework) DecodeNBT(data map[string]any) any {
+	if fireworks, ok := data["Fireworks"].(map[string]any); ok {
+		if explosions, ok := fireworks["Explosions"].([]any); ok {
+			f.Explosions = make([]FireworkExplosion, len(explosions))
+			for i, explosion := range f.Explosions {
+				f.Explosions[i] = explosion.DecodeNBT(explosions[i].(map[string]any)).(FireworkExplosion)
+			}
+		}
+		if durationTicks, ok := fireworks["Flight"].(uint8); ok {
+			f.Duration = time.Duration(durationTicks) * 50 * time.Millisecond
+		}
+	}
+	return f
+}
+
+// RandomisedDuration returns the randomised flight duration of the firework.
+func (f Firework) RandomisedDuration() time.Duration {
+	definite := f.Duration + time.Millisecond*50
+	randomness := time.Duration(rand.Intn(int(time.Millisecond * 600)))
+	return definite*10 + randomness
+}
+
+// EncodeItem ...
+func (Firework) EncodeItem() (name string, meta int16) {
+	return "minecraft:firework_rocket", 0
+}

server/item/firework_explosion.go

@@ -0,0 +1,51 @@
+package item
+
+// FireworkExplosion represents an explosion of a firework.
+type FireworkExplosion struct {
+	// Shape represents the shape of the explosion.
+	Shape FireworkShape
+	// Colour is the colour of the explosion.
+	Colour Colour
+	// Fade is the colour the explosion should fade into. Fades must be set to true in order for this to function.
+	Fade Colour
+	// Fades is true if the explosion should fade into the fade colour.
+	Fades bool
+	// Twinkle is true if the explosion should twinkle on explode.
+	Twinkle bool
+	// Trail is true if the explosion should have a trail.
+	Trail bool
+}
+
+// EncodeNBT ...
+func (f FireworkExplosion) EncodeNBT() map[string]any {
+	data := map[string]any{
+		"FireworkType":    f.Shape.Uint8(),
+		"FireworkColor":   [1]uint8{uint8(invertColour(f.Colour))},
+		"FireworkFade":    [0]uint8{},
+		"FireworkFlicker": boolByte(f.Twinkle),
+		"FireworkTrail":   boolByte(f.Trail),
+	}
+	if f.Fades {
+		data["FireworkFade"] = [1]uint8{uint8(invertColour(f.Fade))}
+	}
+	return data
+}
+
+// DecodeNBT ...
+func (f FireworkExplosion) DecodeNBT(data map[string]any) any {
+	f.Shape = FireworkTypes()[data["FireworkType"].(uint8)]
+	f.Twinkle = data["FireworkFlicker"].(uint8) == 1
+	f.Trail = data["FireworkTrail"].(uint8) == 1
+
+	colours := data["FireworkColor"]
+	if diskColour, ok := colours.([1]uint8); ok {
+		f.Colour = invertColourID(int16(diskColour[0]))
+	} else if networkColours, ok := colours.([]any); ok {
+		f.Colour = invertColourID(int16(networkColours[0].(uint8)))
+	}
+
+	if fades, ok := data["FireworkFade"].([1]uint8); ok {
+		f.Fade, f.Fades = invertColourID(int16(fades[0])), true
+	}
+	return f
+}