sets of interface{}, lol

engine/actor.go

@@ -20,20 +20,20 @@ func init() {
 
 // Actor handles basic movement.
 type Actor struct {
-	CollisionDomain string
+	CollisionDomain string // id of component to look for colliders inside of
 	Pos             image.Point
 	Size            image.Point
 
-	collisionDomain []Collider
-	xRem, yRem      float64
+	xRem, yRem float64
+	game       *Game
 }
 
 func (a *Actor) BoundingRect() image.Rectangle { return image.Rectangle{a.Pos, a.Pos.Add(a.Size)} }
 
 func (a *Actor) CollidesAt(p image.Point) bool {
 	bounds := image.Rectangle{Min: p, Max: p.Add(a.Size)}
-	for _, c := range a.collisionDomain {
-		if c.CollidesWith(bounds) {
+	for c := range a.game.Query(a.CollisionDomain, ColliderType) {
+		if c.(Collider).CollidesWith(bounds) {
 			return true
 		}
 	}
@@ -81,11 +81,7 @@ func (a *Actor) MoveY(dy float64, onCollide func()) {
 }
 
 func (a *Actor) Prepare(g *Game) error {
-	cs := g.Query(a.CollisionDomain, ColliderType)
-	a.collisionDomain = make([]Collider, 0, len(cs))
-	for _, c := range cs {
-		a.collisionDomain = append(a.collisionDomain, c.(Collider))
-	}
+	a.game = g
 	return nil
 }
 

engine/game.go

@@ -33,8 +33,8 @@ type Game struct {
 	Root         DrawUpdater // typically a *Scene or SceneRef though
 
 	dbmu sync.RWMutex
-	byID map[string]Identifier   // Named components by ID
-	byAB map[abKey][]interface{} // Ancestor/behaviour index
+	byID map[string]Identifier              // Named components by ID
+	byAB map[abKey]map[interface{}]struct{} // Ancestor/behaviour index
 }
 
 type abKey struct {
@@ -77,7 +77,7 @@ func (g *Game) Component(id string) Identifier {
 // Query looks for components having both a given ancestor and implementing
 // a given behaviour (see Behaviors in interface.go). This only returns sensible
 // values after LoadAndPrepare. Note that every component is its own ancestor.
-func (g *Game) Query(ancestorID string, behaviour reflect.Type) []interface{} {
+func (g *Game) Query(ancestorID string, behaviour reflect.Type) map[interface{}]struct{} {
 	g.dbmu.RLock()
 	defer g.dbmu.RUnlock()
 	return g.byAB[abKey{ancestorID, behaviour}]
@@ -127,14 +127,14 @@ func (g *Game) LoadAndPrepare(assets fs.FS) error {
 	// Build the component databases
 	g.dbmu.Lock()
 	g.byID = make(map[string]Identifier)
-	g.byAB = make(map[abKey][]interface{})
+	g.byAB = make(map[abKey]map[interface{}]struct{})
 	if err := Walk(g, g.registerComponent); err != nil {
 		return err
 	}
 	g.dbmu.Unlock()
 
 	// Prepare all the Preppers
-	for _, p := range g.Query(g.Ident(), PrepperType) {
+	for p := range g.Query(g.Ident(), PrepperType) {
 		if err := p.(Prepper).Prepare(g); err != nil {
 			return err
 		}
@@ -156,7 +156,10 @@ func (g *Game) registerComponent(c interface{}, path []interface{}) error {
 				continue
 			}
 			k := abKey{i.Ident(), b}
-			g.byAB[k] = append(g.byAB[k], c)
+			if g.byAB[k] == nil {
+				g.byAB[k] = make(map[interface{}]struct{})
+			}
+			g.byAB[k][c] = struct{}{}
 		}
 	}
 

engine/repl.go

@@ -134,7 +134,7 @@ func (g *Game) cmdQuery(dst io.Writer, argv []string) {
 		return
 	}
 
-	for _, c := range x {
+	for c := range x {
 		i, ok := c.(Identifier)
 		if ok {
 			fmt.Fprintf(dst, "%T %s\n", c, i.Ident())