Minimal Scenegraph

[coconParticipant]

Just to make some better organization of the game scenes, I had a look at the Composite pattern. This is a tree pattern (used in scenegraphs) but instead of making distinctions between branches and leafs, I would simply go for one datatype which is a Component that has other components.

Now the next step is that I wanted to have more reusable code, instead the Components be the strong datatype (Component>Player, Component>Enemy) I would care more about how the tree works, rather than specify class system-wide datatypes. The result was that I made the component a generic class.

The result is something like this for now, I post this just in case anyone is interested to know, but later on I will try to make more corrections to it. If you want to make any suggestions or having ideas you are welcomed.

Monkey

#Import "<std>" Using std.. Class Component<T> Private Field name:String Public Property Name:String() Return name End Protected Field children := New List<Component> Public Property HasChildren:Bool() Return children.Count() > 0 End Property Children:List<Component>() Return children End Public Field DataType:T Public Method New(name:String) Self.name = name Self.DataType = New T End Public Field OnUpdate:Void() Field OnUpdateDatatype:Void(c:T) Public Method Add(c:Component) children.Add(c) End Method Remove(c:Component) children.Remove(c) End End Class ComponentFunctions Abstract Function RepeatString:String(s:String, times:Int) Local out := "" For Local i := 0 Until times out += s Next Return out End Public Function PrintTree<T>(component:Component<T>, depth:Int = 0) Print(RepeatString("-", depth * 4) + component.Name) If component.HasChildren > 0 depth += 1 For Local i := Eachin component.Children ComponentFunctions.PrintTree(i, depth) Next depth -= 1 End End Function UpdateTree<T>(component:Component<T>) If component.OnUpdate <> Null Then component.OnUpdate() If component.OnUpdateDatatype <> Null And component.DataType <> Null component.OnUpdateDatatype(component.DataType) End If component.HasChildren > 0 For Local i := Eachin component.Children ComponentFunctions.UpdateTree(i) Next End End End Class DummyClass Field Data:Int End Function Main() ' construct the objects Local w := New Component<DummyClass>("World") Local b := New Component<DummyClass>("Body") Local h := New Component<DummyClass>("Head") Local e := New Component<DummyClass>("Eyes") Local m := New Component<DummyClass>("Mouth") ' add object relations w.Add(b) ' add body to world b.Add(h) ' add head to body h.Add(e) ' add eyes to head h.Add(m) ' add mouth to head ' add some updating functions w.OnUpdate = Lambda() Print("updating world") End b.OnUpdate = Lambda() Print("updating body") End ' add some updating functions to operate upon the datatype h.OnUpdateDatatype = Lambda(c:DummyClass) c.Data += 1 Print("~t~t(data of the head " + c.Data + ")~n") End ' test ComponentFunctions.PrintTree(w) Print("") For Local i := 0 To 5 Print(Millisecs()) ComponentFunctions.UpdateTree(w) Sleep(1) Next End

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#Import "<std>" Using std..   Class Component<T> Private Field name:String Public Property Name:String() Return name End   Protected Field children := New List<Component> Public Property HasChildren:Bool() Return children.Count() > 0 End Property Children:List<Component>() Return children End   Public Field DataType:T   Public Method New(name:String) Self.name = name Self.DataType = New T End   Public Field OnUpdate:Void() Field OnUpdateDatatype:Void(c:T) Public Method Add(c:Component) children.Add(c) End Method Remove(c:Component) children.Remove(c) End End   Class ComponentFunctions Abstract Function RepeatString:String(s:String, times:Int) Local out := "" For Local i := 0 Until times out += s Next Return out End   Public Function PrintTree<T>(component:Component<T>, depth:Int = 0) Print(RepeatString("-", depth * 4) + component.Name) If component.HasChildren > 0 depth += 1 For Local i := Eachin component.Children ComponentFunctions.PrintTree(i, depth) Next depth -= 1 End End Function UpdateTree<T>(component:Component<T>) If component.OnUpdate <> Null Then component.OnUpdate() If component.OnUpdateDatatype <> Null And component.DataType <> Null component.OnUpdateDatatype(component.DataType) End If component.HasChildren > 0 For Local i := Eachin component.Children ComponentFunctions.UpdateTree(i) Next End End End   Class DummyClass Field Data:Int End   Function Main() ' construct the objects Local w := New Component<DummyClass>("World") Local b := New Component<DummyClass>("Body") Local h := New Component<DummyClass>("Head") Local e := New Component<DummyClass>("Eyes") Local m := New Component<DummyClass>("Mouth")   ' add object relations w.Add(b) ' add body to world b.Add(h) ' add head to body h.Add(e) ' add eyes to head h.Add(m) ' add mouth to head   ' add some updating functions w.OnUpdate = Lambda() Print("updating world") End b.OnUpdate = Lambda() Print("updating body") End ' add some updating functions to operate upon the datatype h.OnUpdateDatatype = Lambda(c:DummyClass) c.Data += 1 Print("~t~t(data of the head " + c.Data + ")~n") End ' test ComponentFunctions.PrintTree(w) Print("") For Local i := 0 To 5 Print(Millisecs()) ComponentFunctions.UpdateTree(w) Sleep(1) Next End

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