completed refactoring to use systems

systems/collectible_system.go

@@ -0,0 +1,75 @@
+package systems
+
+import (
+	"fmt"
+	"image"
+	. "openquell/components"
+
+	"github.com/hajimehoshi/ebiten/v2"
+	"github.com/mlange-42/arche/ecs"
+	"github.com/mlange-42/arche/generic"
+)
+
+type CollectibleSystem struct {
+	World            *ecs.World
+	Selector         *generic.Filter3[Position, Collectible, Renderable]
+	EntitiesToRemove []ecs.Entity
+}
+
+func NewCollectibleSystem(world *ecs.World) *CollectibleSystem {
+	system := &CollectibleSystem{
+		Selector: generic.NewFilter3[Position, Collectible, Renderable](),
+		World:    world,
+	}
+
+	return system
+}
+
+func (system *CollectibleSystem) CheckPlayerCollision(
+	playerposition *Position,
+	playervelocity *Velocity) (bool, image.Point) {
+
+	particle_pos := image.Point{}
+	var bumped bool
+
+	query := system.Selector.Query(system.World)
+
+	for query.Next() {
+		colposition, collectible, _ := query.Get()
+
+		ok, _ := playerposition.Intersects(colposition, playervelocity)
+		if ok {
+			fmt.Printf("bumped into collectible %v\n", collectible)
+			system.EntitiesToRemove = append(system.EntitiesToRemove, query.Entity())
+			particle_pos.X = colposition.X
+			particle_pos.Y = colposition.Y
+			bumped = true
+		}
+	}
+
+	return bumped, particle_pos
+}
+
+func (system *CollectibleSystem) Update() {
+	// remove collectible if collected
+	for _, entity := range system.EntitiesToRemove {
+		system.World.RemoveEntity(entity)
+	}
+
+	system.EntitiesToRemove = []ecs.Entity{}
+}
+
+func (system *CollectibleSystem) Draw(screen *ebiten.Image) {
+	// write the movable tiles
+	op := &ebiten.DrawImageOptions{}
+	query := system.Selector.Query(system.World)
+
+	for query.Next() {
+		pos, _, sprite := query.Get()
+
+		op.GeoM.Reset()
+		op.GeoM.Translate(float64(pos.X), float64(pos.Y))
+
+		screen.DrawImage(sprite.Image, op)
+	}
+}

systems/grid_system.go

@@ -0,0 +1,163 @@
+package systems
+
+import (
+	"fmt"
+	"image"
+	"image/draw"
+	"openquell/components"
+	. "openquell/components"
+	. "openquell/config"
+	"openquell/grid"
+
+	"github.com/alecthomas/repr"
+	"github.com/hajimehoshi/ebiten/v2"
+	"github.com/mlange-42/arche/ecs"
+	"github.com/mlange-42/arche/generic"
+)
+
+type GridSystem struct {
+	World                                   *ecs.World
+	Selector                                *generic.Filter3[Renderable, Position, Solid]
+	UseCache                                bool
+	Cache                                   *ebiten.Image
+	Background                              *ebiten.Image
+	Width, Height, TilesX, TilesY, Tilesize int
+	Grid                                    *grid.Grid
+}
+
+func NewGridSystem(world *ecs.World, width, height,
+	tilesize int, background *ebiten.Image) *GridSystem {
+
+	cache := ebiten.NewImage(width, height)
+
+	system := &GridSystem{
+		Selector:   generic.NewFilter3[Renderable, Position, Solid](),
+		UseCache:   false,
+		Cache:      cache,
+		Width:      width,
+		Height:     height,
+		TilesX:     width / tilesize,
+		TilesY:     height / tilesize,
+		Tilesize:   tilesize,
+		Background: background,
+		World:      world,
+	}
+
+	return system
+}
+
+func (system *GridSystem) SetGrid(grid *grid.Grid) {
+	system.Grid = grid
+}
+
+func (system *GridSystem) Update() {}
+
+func (system *GridSystem) Draw(screen *ebiten.Image) {
+	op := &ebiten.DrawImageOptions{}
+
+	if !system.UseCache {
+		// map not cached or cacheable, write it to the cache
+		draw.Draw(system.Cache, system.Background.Bounds(), system.Background, image.ZP, draw.Src)
+
+		query := system.Selector.Query(system.World)
+
+		for query.Next() {
+			sprite, pos, _ := query.Get()
+
+			draw.Draw(
+				system.Cache,
+				image.Rect(pos.X, pos.Y, pos.X+pos.Cellsize, pos.Y+pos.Cellsize),
+				sprite.Image, image.ZP, draw.Over)
+		}
+
+		op.GeoM.Reset()
+		screen.DrawImage(system.Cache, op)
+
+		system.UseCache = true
+	} else {
+		// use the cached map
+		op.GeoM.Reset()
+		screen.DrawImage(system.Cache, op)
+	}
+}
+
+func (system *GridSystem) GetSolidNeighborPosition(
+	position *components.Position,
+	velocity *components.Velocity,
+	solid bool) (bool, *components.Position) {
+
+	if !solid {
+		return false, nil
+	}
+
+	// set to true,  ifwe are already on the last  tile in the current
+	// direction, i.e. on the edge of the grid
+	edge := true
+	neighborpos := position.Point()
+
+	switch velocity.Direction {
+	case East:
+		if neighborpos.X < system.TilesX {
+			neighborpos.X++
+			edge = false
+		}
+	case West:
+		if neighborpos.X > 0 {
+			neighborpos.X--
+			edge = false
+		}
+	case South:
+		if neighborpos.Y < system.TilesY {
+			neighborpos.Y++
+			edge = false
+		}
+	case North:
+		if neighborpos.Y > 0 {
+			neighborpos.Y--
+			edge = false
+		}
+	}
+
+	newpos := components.NewPosition(neighborpos, system.Tilesize)
+	repr.Println(newpos)
+
+	if !edge && system.Grid.Map[neighborpos].Solid {
+		return true, newpos
+	}
+
+	return false, nil
+}
+
+func (system *GridSystem) BumpEdge(
+	pos *components.Position,
+	velocity *components.Velocity) (bool, *components.Position) {
+
+	x := pos.X + velocity.Data.X
+	y := pos.Y + velocity.Data.Y
+
+	if x < 0 || x > system.Width-system.Tilesize || y < 0 || y > system.Height-system.Tilesize {
+		newpos := &components.Position{}
+		X := pos.X
+		Y := pos.Y
+
+		switch velocity.Direction {
+		case East:
+			X = 0
+			fmt.Println("east X=0")
+		case West:
+			X = system.Width - system.Tilesize
+			fmt.Println("west X=max")
+		case South:
+			Y = 0
+			fmt.Println("south y=0")
+		case North:
+			Y = system.Height - system.Tilesize
+			fmt.Println("north y=max")
+		}
+
+		newpos.Update(X, Y, system.Tilesize)
+		return true, newpos
+	}
+
+	return false, nil
+}

systems/particle_system.go

@@ -0,0 +1,73 @@
+package systems
+
+import (
+	"image"
+	. "openquell/components"
+
+	"github.com/hajimehoshi/ebiten/v2"
+	"github.com/mlange-42/arche/ecs"
+	"github.com/mlange-42/arche/generic"
+)
+
+type ParticleSystem struct {
+	World    *ecs.World
+	Selector *generic.Filter2[Position, Particle]
+	Cellsize int
+}
+
+func NewParticleSystem(world *ecs.World, cellsize int) *ParticleSystem {
+	system := &ParticleSystem{
+		Selector: generic.NewFilter2[Position, Particle](),
+		World:    world,
+		Cellsize: cellsize,
+	}
+
+	return system
+}
+
+func (system *ParticleSystem) Update(detonate bool, position *image.Point) {
+	// display debris after collecting
+	query := system.Selector.Query(system.World)
+
+	for query.Next() {
+		// we loop, but it's only one anyway
+		ptposition, particle := query.Get()
+
+		if detonate {
+			// particle appears
+			ptposition.Update(
+				position.X-(system.Cellsize/2),
+				position.Y-(system.Cellsize/2),
+				64,
+			)
+
+			particle.Index = 0 // start displaying the particle
+		} else {
+			switch {
+			// particle shows from earlier tick, animate
+			case particle.Index > -1 && particle.Index < len(particle.Particles)-1:
+				particle.Index++
+			default:
+				// last sprite reached, remove it
+				particle.Index = -1
+			}
+		}
+	}
+}
+
+func (system *ParticleSystem) Draw(screen *ebiten.Image) {
+	// write particles (these are no tiles!)
+	op := &ebiten.DrawImageOptions{}
+	query := system.Selector.Query(system.World)
+
+	for query.Next() {
+		pos, particle := query.Get()
+
+		if particle.Index > -1 {
+			op.GeoM.Reset()
+			op.GeoM.Translate(float64(pos.X), float64(pos.Y))
+			screen.DrawImage(particle.Particles[particle.Index], op)
+		}
+	}
+
+}

systems/player_system.go

@@ -0,0 +1,106 @@
+package systems
+
+import (
+	"fmt"
+	"image"
+	. "openquell/components"
+	. "openquell/config"
+
+	"github.com/hajimehoshi/ebiten/v2"
+	"github.com/mlange-42/arche/ecs"
+	"github.com/mlange-42/arche/generic"
+)
+
+type PlayerSystem struct {
+	World       *ecs.World
+	Selector    *generic.Filter4[Position, Velocity, Player, Renderable]
+	Particle    *ParticleSystem
+	Collectible *CollectibleSystem
+	Grid        *GridSystem
+}
+
+func NewPlayerSystem(world *ecs.World, grid *GridSystem) *PlayerSystem {
+	system := &PlayerSystem{
+		Selector:    generic.NewFilter4[Position, Velocity, Player, Renderable](),
+		Particle:    NewParticleSystem(world, grid.Tilesize),
+		Collectible: NewCollectibleSystem(world),
+		Grid:        grid,
+		World:       world,
+	}
+
+	return system
+}
+
+func (system PlayerSystem) Update() error {
+	query := system.Selector.Query(system.World)
+
+	var bumped bool
+	var particle_pos image.Point
+
+	for query.Next() {
+		playerposition, velocity, _, _ := query.Get()
+
+		if !velocity.Moving() {
+			switch {
+			case ebiten.IsKeyPressed(ebiten.KeyRight):
+				velocity.Change(East)
+			case ebiten.IsKeyPressed(ebiten.KeyLeft):
+				velocity.Change(West)
+			case ebiten.IsKeyPressed(ebiten.KeyDown):
+				velocity.Change(South)
+			case ebiten.IsKeyPressed(ebiten.KeyUp):
+				velocity.Change(North)
+				// other keys: <tab>: switch player, etc
+			}
+		}
+
+		if velocity.Moving() {
+			ok, newpos := system.Grid.BumpEdge(playerposition, velocity)
+			if ok {
+				fmt.Printf("falling off the edge, new pos: %v\n", newpos)
+				playerposition.Set(newpos)
+			} else {
+				ok, tilepos := system.Grid.GetSolidNeighborPosition(playerposition, velocity, true)
+				if ok {
+					intersects, newpos := tilepos.Intersects(playerposition, velocity)
+					if intersects {
+						fmt.Printf("collision detected. tile: %s\n", tilepos)
+						fmt.Printf("                  player: %s\n", playerposition)
+						fmt.Printf("                     new: %s\n", newpos)
+
+						playerposition.Set(newpos)
+						fmt.Printf("              player new: %s\n", playerposition)
+						velocity.Change(Stop)
+					}
+				}
+			}
+
+			bumped, particle_pos = system.Collectible.CheckPlayerCollision(playerposition, velocity)
+		}
+
+		playerposition.Move(velocity)
+	}
+
+	system.Particle.Update(bumped, &particle_pos)
+	system.Collectible.Update()
+
+	return nil
+}
+
+func (system *PlayerSystem) Draw(screen *ebiten.Image) {
+	// write the movable tiles
+	op := &ebiten.DrawImageOptions{}
+	query := system.Selector.Query(system.World)
+
+	for query.Next() {
+		pos, _, _, sprite := query.Get()
+
+		op.GeoM.Reset()
+		op.GeoM.Translate(float64(pos.X), float64(pos.Y))
+
+		screen.DrawImage(sprite.Image, op)
+	}
+
+	system.Collectible.Draw(screen)
+	system.Particle.Draw(screen)
+}

systems/system.go

@@ -1,4 +1,4 @@
-package system
+package systems
 
 import "github.com/hajimehoshi/ebiten/v2"