Inheritance

I'm having inheritance problems, heres an example that hopefully is indicative of my problems.

I have a type GameObject:

Type GameObject Abstract


	Field ID
	Field dead
	
	
	Method update(deltaT#) Abstract
	
	
	Method setInput(inputData:TList) Abstract
	

	Method getOutput:TList() Abstract
	
	
	Method draw() Abstract
	
	
End Type

And I have a projectile which extends it:

Type Projectile Extends GameObject
	
	
	Method update(deltaT:Float)
	
		Print "updating"

	End Method
	
	
	Method setInput(inputData:TList)
	End Method
	

	Method getOutput:TList()
	End Method
	
	
	
	Method draw()
		print "drawing"
	End Method
	
	
	Function create:projectile(info:projectileInfo, firerID, targetBase, targetOther, x#, y#, rot#, vx#=0, vy#=0, vrot#=0)
		
	End Function
	
End Type

I have a bunch of projectiles in a list, and I run through the list calling ".update()" on them and I don't get any print out. Anyone know what is wrong, and have any sage tips on how inheritance in bmax might be a bit unusual?

You have a list of projectiles or Gameobjects?

if gameobjects you need to cast to pprojectiles

a= projectile (The specific GameObject)

Its a list of projectiles. Now the plot thickens, however:

I did a simple test:

1) I modified Projectile so that it doesn't extend GameObject
2) I created a new projectile
3) I called myProj.update(.5) and nothing happened! It doesn't call the update!

Now I'm really freaking out, I can't figure out why that would be!

Import "Code/Includes.bmx"





GameData.current = New Gamedata
GameData.current.loadGameData("Data/DataManifest.txt")

Graphics 1680, 1050

Pip:projectileInfo = GameData.current.projectileInfoNamed("Gatling Laser")
np:projectile = projectile.create:projectile(pip, 0, 0, 0, MouseX(), MouseY(), 0)


Global deltaT#, lasttime = MilliSecs()
While Not(KeyHit(key_escape))
	deltaT = (MilliSecs() - lasttime)*.001; lasttime = MilliSecs()
	
	If MouseHit(1) Then
		Pip:projectileInfo = GameData.current.projectileInfoNamed("Gatling Laser")
		np:projectile = projectile.create:projectile(pip, 0, 0, 0, MouseX(), MouseY(), 0)
	End If
	
	np.update(DeltaT)
	np.draw()
	
	Flip; Cls;
Wend

Update never gets called! argh, this is freaking me out!

I shouldn't think so, the update method in the parent type is abstracted so surely the overridden method in the type should be called without the need to cast.

	Method updateProjectiles()
		For p:projectile = EachIn projectiles
			DebugStop()
			If p.dead Then 
				ListRemove(projectiles, p)
			Else
				p.update(deltaT)
			End If
		Next
	End Method

That was the original source, thats a method in Simulation which has a list of projectiles which it runs through, I've verified that it makes it to the line right p.update(deltaT)

Also, in the post above yours I have it being called not from an item in a list.

Thats pretty odd, have you tried putting a breakpoint inside the update method to see if its actually being called but that the code inside is not producing the desired results?

Does this work for you...

Type projectileinfo
End type
Type Projectile 	
	
	Method update(deltaT:Float)
	
		Print "updating"

	End Method
	
	
	Method setInput(inputData:TList)
	End Method
	

	Method getOutput:TList()
	End Method
	
	
	
	Method Draw()
		Print "drawing"
	End Method
	
	
	Function create:projectile(info:projectileInfo, firerID, targetBase, targetOther, x#, y#, rot#, vx#=0, vy#=0, vrot#=0)
		
	End Function
	
End Type

myproj:projectile = New projectile
myproj.update(0.5)

?
If so, your problem is somewhere else.
<edit> Arrrgh editing while I'm typing.

tonyg - thanks, that works, the problem must be somewhere else then. Do you have any experience with what might cause a method to not call right?

Helios - yes, i tried making debugstop the first line in update(DeltaT#) and it doesn't get called.

Nope, I agree you should put a debugstop or, my preferred method, add an 'Entering xxx', 'Exiting xxx' debug statement to each of my functions and methods.

first, my best advice... use SuperStrict! Really...

that shouldn't matter...

SuperStrict

Type GameObject Abstract
	Field ID:Int
	Field dead:Int
	
	Method update(deltaT#) Abstract
	Method setInput(inputData:TList) Abstract
	Method getOutput:TList() Abstract
	Method draw() Abstract
	
End Type

Type Projectile Extends GameObject
	
	Method update(deltaT:Float)
		Print "updating"
	End Method
	
	Method setInput(inputData:TList)
	End Method
	
	Method getOutput:TList()
	End Method
	
	Method draw()
		Print "drawing"
	End Method
	
End Type


Local list:TList = New TList
For Local i:Int = 0 To 10
	list.AddLast(New Projectile)
Next

For Local go:GameObject = EachIn list
	go.update(1.0)
Next

the above prints "updating" for each object.

Ok, I think i've figured it out. Somehow the objects were getting replaced with something that inherited from Projectile :P I'm sorry to have led us on this wild goose chase - and thanks so much for all your help!