feat(world): add a creationID variable to keep track of actors ID

CHANGELOG.md

@@ -27,6 +27,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - **world:** Support batching actor loading
 
+- **world:** Add `Actor.creationID` to keep the order in which actors have been created
+
 ### Changed
 
 - **world:** automatize world integration in a scene

gamecore/modules/world/baseworld.lua

@@ -84,6 +84,7 @@ end
 
 function BaseWorld:initActors( )
   self.actors = {}
+  self.currentCreationID = 0
 end
 
 function BaseWorld:newActor(name, x, y)
@@ -95,6 +96,8 @@ function BaseWorld:newCollision(name, x, y, w, h)
 end
 
 function BaseWorld:registerActor(actor)
+  actor.creationID = self.currentCreationID
+  self.currentCreationID = self.currentCreationID + 1
   table.insert(self.actors, actor)
 end
 

gamecore/modules/world/world2D.lua

@@ -38,10 +38,13 @@ end
 -- Wrappers around Bump2D functions
 
 function World2D:initActors()
-  self.actors   = Bump.newWorld(50)
+  self.currentCreationID  = 0
+  self.actors = Bump.newWorld(50)
 end
 
 function World2D:registerActor(actor)
+  actor.creationID        = self.currentCreationID
+  self.currentCreationID  = self.currentCreationID + 1
   return self.actors:add(actor, actor.x, actor.y, actor.w, actor.h)
 end