Added weapon drops and collection. New laser item asset.

assets/imagebank.go

@@ -29,6 +29,7 @@ const (
 	Fireball      ImgAssetName = "Fireball"
 	Splash        ImgAssetName = "Splash"
 	LaserBeam     ImgAssetName = "LaserBeam"
+	ItemLaser     ImgAssetName = "ItemLaser"
 )
 
 var (
@@ -66,6 +67,8 @@ var (
 	splash_img []byte
 	//go:embed laserbeam.png
 	laserbeam_img []byte
+	//go:embed item-laser.png
+	itemlaser_img []byte
 )
 
 func LoadImages() {
@@ -87,6 +90,7 @@ func LoadImages() {
 	ImageBank[Fireball] = LoadImagesFatal(fireball_img)
 	ImageBank[Splash] = LoadImagesFatal(splash_img)
 	ImageBank[LaserBeam] = LoadImagesFatal(laserbeam_img)
+	ImageBank[ItemLaser] = LoadImagesFatal(itemlaser_img)
 
 }
 

elements/weapondrop.go

@@ -0,0 +1,66 @@
+package elements
+
+import (
+	"math"
+	"mover/assets"
+	"mover/gamedata"
+
+	"github.com/hajimehoshi/ebiten/v2"
+)
+
+type WeaponDrop struct {
+	Sprite     *ebiten.Image
+	position   gamedata.Coordinates
+	weapontype gamedata.WeaponType
+	cycle      int
+	collected  bool
+}
+
+func NewWeaponDrop(wt gamedata.WeaponType) *WeaponDrop {
+	wp := &WeaponDrop{
+		Sprite:     ebiten.NewImage(32, 32),
+		weapontype: wt,
+		cycle:      0,
+		collected:  false,
+	}
+	return wp
+}
+
+func (wp *WeaponDrop) SetPosition(pos gamedata.Coordinates) {
+	wp.position = pos
+}
+
+func (wp *WeaponDrop) GetPosition() gamedata.Coordinates {
+	return wp.position
+}
+
+func (wp *WeaponDrop) GetWeaponType() gamedata.WeaponType {
+	return wp.weapontype
+}
+
+func (wp *WeaponDrop) Update() error {
+	wp.cycle++
+	return nil
+}
+
+func (wp *WeaponDrop) Draw() {
+	wp.Sprite.Clear()
+
+	dy := 2 * math.Sin(float64(wp.cycle)/(math.Pi*2))
+	op := &ebiten.DrawImageOptions{}
+	op.GeoM.Translate(0, dy)
+
+	switch wp.weapontype {
+	case gamedata.WeaponTypeLaser:
+		wp.Sprite.DrawImage(assets.ImageBank[assets.ItemLaser], op)
+	}
+
+}
+
+func (wp *WeaponDrop) SetCollected(c bool) {
+	wp.collected = c
+}
+
+func (wp *WeaponDrop) IsCollected() bool {
+	return wp.collected
+}

gameelement/canvas.go

@@ -35,6 +35,7 @@ type Canvas struct {
 	counter       int
 	score         int
 	splashes      []*elements.Splash
+	wpdrops       []*elements.WeaponDrop
 	hero          *elements.Hero
 	charge        *elements.Explosion
 	goblin        *elements.FlyGoblin
@@ -82,6 +83,7 @@ func (c *Canvas) Update() error {
 		c.Initialize()
 	} else {
 		c.UpdateHero()
+		c.UpdateWeaponDrops()
 		c.UpdateWeapons()
 		c.UpdateProjectiles()
 		c.UpdateCharge()
@@ -90,6 +92,7 @@ func (c *Canvas) Update() error {
 		c.CleanupTargets()
 		c.UpdateSplashes()
 		c.CleanSplashes()
+		c.CleanupDrops()
 		c.counter++
 	}
 
@@ -135,6 +138,14 @@ func (c *Canvas) Draw(drawimg *ebiten.Image) {
 		}
 	}
 
+	//draw weapon drops
+	for _, drop := range c.wpdrops {
+		drop.Draw()
+		op := &ebiten.DrawImageOptions{}
+		op.GeoM.Translate(drop.GetPosition().X-float64(drop.Sprite.Bounds().Dx())/2, drop.GetPosition().Y-float64(drop.Sprite.Bounds().Dy())/2)
+		c.Sprite.DrawImage(drop.Sprite, op)
+	}
+
 	//draw enemies
 	for _, e := range c.enemies {
 		e.Draw()
@@ -212,6 +223,7 @@ func (c *Canvas) Initialize() {
 
 	c.InitializeHero()
 	c.CleanSplashes()
+	c.ResetWeaponDrops()
 	c.enemies = c.enemies[:0]
 	c.gameover = false
 	c.initialized = true
@@ -536,6 +548,16 @@ func (c *Canvas) CleanupTargets() {
 	// remove dead targets by iterating over all targets
 	i := 0
 	for _, e := range c.enemies {
+
+		//compute odds for dropping an item on dead enemies
+		if e.GetEnemyState() == elements.MoverActionDead {
+			if rand.Float64() > 0.98 {
+				drop := elements.NewWeaponDrop(gamedata.WeaponTypeLaser)
+				drop.SetPosition(e.GetPosition())
+				c.wpdrops = append(c.wpdrops, drop)
+			}
+		}
+
 		//moving valid targets to the front of the slice
 		if e.GetEnemyState() < elements.MoverActionDead &&
 			!(e.GetPosition().X < -640*2 || e.GetPosition().X > 640*2 ||
@@ -847,7 +869,7 @@ func (c *Canvas) LaserAttempt4() {
 		}
 		//fmt.Printf("%f \n", a)
 
-		if d <= 50 && e.GetEnemyState() <= gamedata.EnemyStateHit {
+		if d <= float64(e.GetSprite().Bounds().Dx()) && e.GetEnemyState() <= gamedata.EnemyStateHit {
 
 			if IsPixelColliding(c.laserMask, e.GetSprite(),
 				image.Pt(0, 0),
@@ -890,6 +912,22 @@ func (c *Canvas) CleanSplashes() {
 	c.splashes = c.splashes[:i]
 }
 
+func (c *Canvas) CleanupDrops() {
+	i := 0
+	for _, drop := range c.wpdrops {
+		if !drop.IsCollected() {
+			c.wpdrops[i] = drop
+			i++
+		}
+	}
+
+	for j := i; j < len(c.wpdrops); j++ {
+		c.wpdrops[j] = nil
+	}
+
+	c.wpdrops = c.wpdrops[:i]
+}
+
 func (c *Canvas) UpdateWeapons() {
 	if !c.gameover {
 		//check for weapon inputs
@@ -909,3 +947,41 @@ func (c *Canvas) UpdateWeapons() {
 	}
 
 }
+
+func (c *Canvas) UpdateWeaponDrops() {
+	//do we have any drops? let's calculate the chances
+	//
+
+	for _, drop := range c.wpdrops {
+		drop.Update()
+
+		//has the hero collided with any? add to holster
+		//boundary box collision check
+		if c.hero.Pos.X >= drop.GetPosition().X-float64(drop.Sprite.Bounds().Dx())/2 &&
+			c.hero.Pos.X <= drop.GetPosition().X+float64(drop.Sprite.Bounds().Dx())/2 &&
+			c.hero.Pos.Y >= drop.GetPosition().Y-float64(drop.Sprite.Bounds().Dy())/2 &&
+			c.hero.Pos.Y <= drop.GetPosition().Y+float64(drop.Sprite.Bounds().Dy())/2 {
+			//fmt.Println("hero trying to pick up weapon maybe")
+
+			if IsPixelColliding(
+				c.hero.Sprite,
+				drop.Sprite,
+				image.Pt(int(c.hero.Pos.X), int(c.hero.Pos.Y)),
+				image.Pt(int(drop.GetPosition().X), int(drop.GetPosition().Y)),
+			) {
+				fmt.Println("weapon acquired")
+				drop.SetCollected(true)
+				c.holster.AddWeapon(weapons.NewLaser())
+			}
+
+		}
+	}
+
+}
+
+func (c *Canvas) ResetWeaponDrops() {
+	for i := range c.wpdrops {
+		c.wpdrops[i] = nil
+	}
+	c.wpdrops = c.wpdrops[:0]
+}

screenmanager/manager.go

@@ -26,7 +26,7 @@ func NewManager() Manager {
 	return Manager{
 		Info: gamedata.GameInfo{
 			Name:    "survive",
-			Version: "0.30",
+			Version: "0.32",
 			Dimensions: gamedata.Area{
 				Width:  defaultWidth,
 				Height: defaultHeight,

weapons/holster.go

@@ -13,7 +13,7 @@ func NewHolster() *Holster {
 		activewp: gamedata.WeaponTypeGun,
 	}
 	holster.AddWeapon(NewGun())
-	holster.AddWeapon(NewLaser())
+	//holster.AddWeapon(NewLaser())
 	return holster
 }
 
@@ -46,8 +46,9 @@ func (h *Holster) CycleWeapon() {
 	}
 
 	//keep searching until we find the next weapon that exists
+	var nextwp gamedata.WeaponType = h.activewp
 	for ok := false; !ok; {
-		nextwp := (h.activewp + 1) % gamedata.WeaponTypeMax
+		nextwp = (nextwp + 1) % gamedata.WeaponTypeMax
 		_, ok = h.guns[nextwp]
 		if ok {
 			h.activewp = nextwp