added detonation particles after collectibles have been collected

assets/loader-levels.go

@@ -28,6 +28,8 @@ type Tile struct {
 	Renderable  bool
 	Velocity    bool
 	Collectible bool
+	Particle    int // -1=unused, 0-3 = show image of slice
+	Particles   []*ebiten.Image
 }
 
 func NewTilePlayer() *Tile {
@@ -62,6 +64,23 @@ func NewTileCollectible(class string) *Tile {
 	}
 }
 
+func NewTileParticle(class []string) *Tile {
+	sprites := []*ebiten.Image{}
+
+	for _, sprite := range class {
+		sprites = append(sprites, Assets[sprite])
+	}
+
+	return &Tile{
+		Id:         '*',
+		Class:      "particle",
+		Solid:      false,
+		Renderable: false,
+		Particle:   -1,
+		Particles:  sprites,
+	}
+}
+
 // used to map level data bytes to actual tiles
 type TileRegistry map[byte]*Tile
 
@@ -90,6 +109,10 @@ func InitTiles() TileRegistry {
 		'#': NewTileBlock("block-grey32"),
 		'S': NewTilePlayer(),
 		'o': NewTileCollectible("collectible-orange"),
+		'*': NewTileParticle([]string{
+			"particle-dust-0", "particle-dust-0", "particle-dust-1", "particle-dust-1",
+			"particle-dust-0", "particle-dust-2", "particle-dust-3", "particle-dust-3",
+		}),
 	}
 }
 

components/components.go

@@ -16,3 +16,8 @@ type Solid struct{}
 type Floor struct{}
 type Player struct{}
 type Collectible struct{}
+
+type Particle struct {
+	Index     int
+	Particles []*ebiten.Image
+}

game/grid.go

@@ -46,6 +46,11 @@ func NewGrid(game *Game, tilesize int, mapslice map[image.Point]*assets.Tile) *G
 		components.Renderable,
 		components.Collectible](game.World)
 
+	ptmapper := generic.NewMap2[
+		components.Position,
+		components.Particle,
+	](game.World)
+
 	var pos *components.Position
 	var render *components.Renderable
 
@@ -81,6 +86,12 @@ func NewGrid(game *Game, tilesize int, mapslice map[image.Point]*assets.Tile) *G
 		pos.Update(point.X*tilesize, point.Y*tilesize, tilesize)
 	}
 
+	// not part of the grid, but add them as well
+	entity := ptmapper.New()
+	_, particle := ptmapper.Get(entity)
+	particle.Index = assets.Tiles['*'].Particle
+	particle.Particles = assets.Tiles['*'].Particles
+
 	return &Grid{
 		Size:     len(mapslice),
 		Tilesize: tilesize,

game/levels.go

@@ -36,16 +36,25 @@ func NewLevel(game *Game, cellsize int, plan *assets.RawLevel) *Level {
 	velocityid := ecs.ComponentID[components.Velocity](game.World)
 	playerid := ecs.ComponentID[components.Player](game.World)
 	colid := ecs.ComponentID[components.Collectible](game.World)
+	ptid := ecs.ComponentID[components.Particle](game.World)
+	sid := ecs.ComponentID[components.Solid](game.World)
+	renderid := ecs.ComponentID[components.Renderable](game.World)
 
 	selectors := map[string]ecs.Mask{}
 	selectors["player"] = filter.All(positionid, velocityid, playerid)
+	selectors["tile"] = filter.All(renderid, positionid, sid)
+	selectors["movable"] = filter.All(renderid, positionid)
 	selectors["collectible"] = filter.All(positionid, colid)
+	selectors["particle"] = filter.All(positionid, ptid)
 
 	components := map[string]ecs.ID{}
 	components["position"] = positionid
 	components["velocity"] = velocityid
 	components["player"] = playerid
 	components["collectible"] = colid
+	components["particle"] = ptid
+	components["solid"] = sid
+	components["renderable"] = renderid
 
 	return &Level{
 		Mapslice:    LevelToSlice(game, plan, cellsize),
@@ -66,6 +75,7 @@ func (level *Level) Update() {
 	query := level.World.Query(level.Selector["player"])
 
 	toRemove := []ecs.Entity{}
+	particle_pos := image.Point{}
 
 	for query.Next() {
 		playerposition := (*components.Position)(query.Get(level.Component["position"]))
@@ -114,6 +124,8 @@ func (level *Level) Update() {
 				if ok {
 					fmt.Printf("bumped into collectible %v\n", collectible)
 					toRemove = append(toRemove, colquery.Entity())
+					particle_pos.X = colposition.X
+					particle_pos.Y = colposition.Y
 				}
 			}
 		}
@@ -121,11 +133,39 @@ func (level *Level) Update() {
 		playerposition.Move(velocity)
 	}
 
+	// remove collectible if collected
 	for _, entity := range toRemove {
 		// FIXME: or keep them and prepare an animated death
 		level.World.RemoveEntity(entity)
 	}
 
+	// display debris after collecting
+	ptquery := level.World.Query(level.Selector["particle"])
+	for ptquery.Next() {
+		// we loop, but it's only one anyway
+		particle := (*components.Particle)(ptquery.Get(level.Component["particle"]))
+		colposition := (*components.Position)(ptquery.Get(level.Component["position"]))
+
+		if len(toRemove) > 0 {
+			// particle appears
+			colposition.Update(
+				particle_pos.X-(level.Cellsize/2),
+				particle_pos.Y-(level.Cellsize/2),
+				64,
+			)
+
+			particle.Index = 0 // start displaying the particle
+		} else {
+			switch {
+			case particle.Index > -1 && particle.Index < len(particle.Particles)-1:
+				particle.Index++
+			default:
+				// last sprite reached, remove it
+				particle.Index = -1
+			}
+		}
+	}
+
 }
 
 func (level *Level) Position2Point(position *components.Position) image.Point {
@@ -136,7 +176,10 @@ func (level *Level) Position2Point(position *components.Position) image.Point {
 }
 
 // return the tile the moving object would end up on if indeed moving
-func (level *Level) GetTile(position *components.Position, velocity *components.Velocity) *assets.Tile {
+func (level *Level) GetTile(
+	position *components.Position,
+	velocity *components.Velocity) *assets.Tile {
+
 	newpoint := image.Point{
 		int(position.X+velocity.Data.X) / level.Cellsize,
 		int(position.Y+velocity.Data.Y) / level.Cellsize,
@@ -147,20 +190,22 @@ func (level *Level) GetTile(position *components.Position, velocity *components.
 }
 
 func (level *Level) Draw(screen *ebiten.Image) {
-	rid := ecs.ComponentID[components.Renderable](level.World)
-	pid := ecs.ComponentID[components.Position](level.World)
-	sid := ecs.ComponentID[components.Solid](level.World)
+	level.DrawTiles(screen)
+	level.DrawMovables(screen)
+	level.DrawParticles(screen)
+}
+
+func (level *Level) DrawTiles(screen *ebiten.Image) {
+	op := &ebiten.DrawImageOptions{}
 
 	if !level.UseCache {
 		// map not cached or cacheable, write it to the cache
 		draw.Draw(level.Cache, level.Background.Bounds(), level.Background, image.ZP, draw.Src)
 
-		selector := filter.All(rid, pid, sid)
-
-		query := level.World.Query(selector)
+		query := level.World.Query(level.Selector["tile"])
 		for query.Next() {
-			pos := (*components.Position)(query.Get(pid))
-			sprite := (*components.Renderable)(query.Get(rid))
+			pos := (*components.Position)(query.Get(level.Component["position"]))
+			sprite := (*components.Renderable)(query.Get(level.Component["renderable"]))
 
 			draw.Draw(
 				level.Cache,
@@ -168,31 +213,52 @@ func (level *Level) Draw(screen *ebiten.Image) {
 				sprite.Image, image.ZP, draw.Over)
 		}
 
-		op := &ebiten.DrawImageOptions{}
+		op.GeoM.Reset()
 		screen.DrawImage(level.Cache, op)
 
 		level.UseCache = true
 	} else {
 		// use the cached map
-		op := &ebiten.DrawImageOptions{}
+		op.GeoM.Reset()
 		screen.DrawImage(level.Cache, op)
 	}
+}
 
+func (level *Level) DrawMovables(screen *ebiten.Image) {
 	// write the movable tiles
-	selector := filter.All(rid, pid).Without(sid)
-
-	query := level.World.Query(&selector)
-	for query.Next() {
-		pos := (*components.Position)(query.Get(pid))
-		sprite := (*components.Renderable)(query.Get(rid))
-
 	op := &ebiten.DrawImageOptions{}
+	selector := level.Selector["movable"].Without(level.Component["solid"])
+	query := level.World.Query(&selector)
+
+	for query.Next() {
+		pos := (*components.Position)(query.Get(level.Component["position"]))
+		sprite := (*components.Renderable)(query.Get(level.Component["renderable"]))
+
+		op.GeoM.Reset()
 		op.GeoM.Translate(float64(pos.X), float64(pos.Y))
 
 		screen.DrawImage(sprite.Image, op)
 	}
 }
 
+func (level *Level) DrawParticles(screen *ebiten.Image) {
+	// write particles (these are no tiles!)
+	op := &ebiten.DrawImageOptions{}
+	query := level.World.Query(level.Selector["particle"])
+
+	for query.Next() {
+		pos := (*components.Position)(query.Get(level.Component["position"]))
+		particle := (*components.Particle)(query.Get(level.Component["particle"]))
+
+		if particle.Index > -1 {
+			op.GeoM.Reset()
+			op.GeoM.Translate(float64(pos.X), float64(pos.Y))
+			screen.DrawImage(particle.Particles[particle.Index], op)
+		}
+	}
+
+}
+
 func (level *Level) SetupGrid(game *Game) {
 	level.Grid = NewGrid(game, level.Cellsize, level.Mapslice)
 }