Name change

internal/projectile/projectile.go

@@ -0,0 +1,95 @@
+package projectile
+
+import (
+	"image/color"
+
+	"github.com/hajimehoshi/ebiten/v2"
+	"github.com/hajimehoshi/ebiten/v2/vector"
+)
+
+type ProjectileConfig struct {
+	Speed  float64
+	Radius float64
+	Color  color.NRGBA
+}
+
+type Projectile struct {
+	X         float64
+	Y         float64
+	VelocityX float64
+	VelocityY float64
+	Radius    float64
+	Color     color.NRGBA
+	Active    bool
+}
+
+func New(x, y, directionX, directionY float64, config ProjectileConfig) *Projectile {
+	return &Projectile{
+		X:         x,
+		Y:         y,
+		VelocityX: directionX * config.Speed,
+		VelocityY: directionY * config.Speed,
+		Radius:    config.Radius,
+		Color:     config.Color,
+		Active:    true,
+	}
+}
+
+func (p *Projectile) Update(dt float64, screenWidth, screenHeight float64) {
+	p.X += p.VelocityX * dt
+	p.Y += p.VelocityY * dt
+
+	if p.X < 0 || p.X > screenWidth || p.Y < 0 || p.Y > screenHeight {
+		p.Active = false
+	}
+}
+
+func (p *Projectile) Draw(screen *ebiten.Image) {
+	if !p.Active {
+		return
+	}
+	vector.DrawFilledCircle(
+		screen,
+		float32(p.X),
+		float32(p.Y),
+		float32(p.Radius),
+		p.Color,
+		false,
+	)
+}
+
+type Manager struct {
+	Projectiles []*Projectile
+}
+
+func NewManager() *Manager {
+	return &Manager{
+		Projectiles: make([]*Projectile, 0),
+	}
+}
+
+func (m *Manager) Shoot(x, y, directionX float64, config ProjectileConfig) {
+	p := New(x, y, directionX, 0, config)
+	m.Projectiles = append(m.Projectiles, p)
+}
+
+func (m *Manager) Update(dt float64, screenWidth, screenHeight float64) {
+	for i := len(m.Projectiles) - 1; i >= 0; i-- {
+		p := m.Projectiles[i]
+		p.Update(dt, screenWidth, screenHeight)
+
+		if !p.Active {
+			m.Projectiles = append(m.Projectiles[:i], m.Projectiles[i+1:]...)
+		}
+	}
+}
+
+func (m *Manager) Draw(screen *ebiten.Image) {
+	for _, p := range m.Projectiles {
+		p.Draw(screen)
+	}
+}
+
+func (m *Manager) Clear() {
+	m.Projectiles = make([]*Projectile, 0)
+}