OOP dilemna

I have these classes:

Entity
Light Extends Entity
PointLight Extends Light
SpotLight Extends Light

Then I have a list of Light classes that affect a certain entity. I want to get some information about the light that is specific to one of the light subclasses, like the cone angle of the spotlight. I can't get at it easily, because the cone angle parameter is part of the "SpotLight" type, and I have the handle to the Super "Light" type.

I can easily solve this by moving the coneangle field from the "SpotLight" type to the Super "Light" type, but it's not very nice.

Any suggestions?

Check if it casts to SpotLight?

What Azathoth means:

Local spot:SpotLight = SpotLight(YourLight)
If spot Then
    Print "Is a spotlight"
EndIf

I'd prefer to place a class ID in the light entity to check before casting just because it would save time.

However, I'm more in favor the component-object entity system than the current means of just extending things each time I need some new functionality. Instead of doing that, I just add a new component to its list of components and the functionality is added, so it's like I can have multiple inheritance rather than extending a single existing type.

There's a crude example of this in my code archive entries and it's covered in Game Programming Gems 5.

That's an interesting way to test a type. In Delphi you can say "If Yourlist is Spotlight" which is pretty cool. Another way is to have a tag in the Light field which defines the type of type it is, then you can just query that later on.

Would suggest the second way as well.

Create a field _type:String in your entity class and any extended class assings usefull data to that in its default constructor (method new() )

I'm not sure if this solves your problem but it might. You can loop any object type in your Tlist.

'Loop all SpotLights in your LightList
For local Light:SpotLight = Eachin LightList
     If Light.Radius > Light.Cone
       'do what you want
     Endif
Next
'Loop all PointLights in your LightList
For local Light:PointLight = Eachin LightList
     If Light.PointCenter < Z
       'Do something :)
     Endif
     'In this case Light is always of the Pointlight type.
Next