How is my BlitzMax and OOP programming?

I'm looking to get some tips on my BlitzMax and OOP programming.

I'm looking for ways I can improve on and some gotchas I don't know about.
I am having a bit of a problem with scaling, so I would appreciate help on that.

What the program is suppose to do is load six images into a list. And then cycles thru the list and scale each image 10x its size, along with fading it out and then remove the object from the list.
Then when the list is empty start over again.

Strict
Graphics 800,600,0

Global ImageList:TList = New TList

'string array
Global arrPath:String[]=["gfx/blue.bmp","gfx/green.bmp","gfx/yellow.bmp","gfx/red.bmp","gfx/orange.bmp","gfx/violet.bmp"]

'loading path to graphics
'and create objects
Function LoadPieces()
	For Local i:String = EachIn arrPath
		Image.Create(i)
	Next
End Function
 

Type Image
            Global ImageListCount:Int =0
            Field xpos,ypos:Int
            Field _image:TImage = New TImage
            Field AlphaLevel:Int =1.0


             'instantiate and each object to List
            Function Create:Image(strPath:String)
                        Local img:Image = New Image
                        img._image = LoadImage(strPath )
                        ListAddLast ImageList, img 
            End Function 

            'constructor
            Method New()
                        ImageListCount:+1
                        xpos = (GraphicsWidth() / 2)
                        ypos = (GraphicsHeight() / 2)

            End Method

		 'go thru each object, scale it and fade object
             Method Update()
                        Global scale:Int
				SetBlend ALPHABLEND
                        For Local i:Image = EachIn ImageList
					MidHandleImage i._image
					While (1)
						Cls
						SetScale scale,scale
						SetAlpha i.AlphaLevel
						DrawImage i._image, (i.xpos), i.ypos
						Flip
				
						scale:+1
						i.AlphaLevel:-0.5
						If scale >= 10 Then
							ListRemove ImageList, i
							scale=1.0
							i.AlphaLevel=1.0
							Exit
						EndIf
					Wend
                        Next
			FlushMem()
			
			'after all objects are destroyed, load objects again and repeat process
			Reset()     
           End Method

	   Method Reset()
		      If ListIsEmpty(ImageList) = True  Then
		   		LoadPieces()			
	   	      EndIf	
	   End Method
End Type

Local i:Image = New Image

'main
While Not KeyHit(KEY_ESCAPE)
            i.update()
Wend

'destroy i or blitz takes care of this for me when
'the program ends
i=Null

You've set scale as an Int when it should be a float.
Haven't looked at anything else.

Well here you go:

Or double. Also, the same is true for Alpha.
As far as I can tell, this is redundant since all images are stored in a List anyway.

Additionally you have a problem with creation responsability. Since New() cannot be made private you should use either New(), or the Create Function (Simple Factory). Moving the lines in the New() method to the Create Function would solve this, and additionally you should only increase the count, and add an object to the list, if image loading was actually successful.

Additionally there's a potential problem with the Update method. Does having a Global here actually work? Shouldn't scale be a Field (maybe even a Global/static one) like Alphalevel?

Also the update method has way too many different responsabilities. It would be better to seperate the update (queue management, etc.) and actual rendering (fade/scale, drawimage) in seperate methods. Additionally Cls/Flip/Flushmem etc. should be moved to the main loop.

The main loop could then look something like:

While Not KeyHit(KEY_ESCAPE)
  Cls
  i.update()
  i.render()
  Flip
  Flushmem
Wend

Other than that it looks perfectly reasonable.

OK, I made some changes. How is this?

Strict
Graphics 800,600,0,20

Type Image
	Global ImageList:TList
        Field xpos,ypos:Int
        Field _image:TImage 
	Field AlphaLevel:Float 
	Field Scale:Float 
	

             'instantiate and each object to List
            Function Create:Image(startXpos:Int,startYpos:Int,imgAlpha:Float,imgScale:Float)
			Local arrPath:String[]=["gfx/blue.bmp","gfx/green.bmp","gfx/yellow.bmp","gfx/red.bmp","gfx/orange.bmp","gfx/violet.bmp"]
			
			For Local i:String = EachIn arrPath
  	                      Local img:Image = New Image
  	                      img._image = LoadImage(i)
  	                      img.xpos = startXpos
  	                      img.ypos = startYpos
			      img.AlphaLevel = imgAlpha
			      img.Scale = imgScale
			Next
            End Function 

     Method New ()
            If ImageList = Null
               ImageList = New TList
            EndIf
            ImageList.AddLast Self
     End Method
	
	'go thru each object, scale it and fade object
        Method Update()'img:Image)
		Scale:+1.0
		AlphaLevel:-0.1  
        End Method

	Function Render()
		SetBlend ALPHABLEND
			If ((ImageList = Null)  Or (ImageList.Count() = 0)) Then Return
				Local i:Image = Image(ImageList.First())
				MidHandleImage i._image
				SetScale i.Scale,i.Scale
				SetAlpha i.AlphaLevel
				DrawImage i._image, (i.xpos), i.ypos
				If i.Scale >= 15.0 Then
					ListRemove ImageList,i
					i.Scale=1.0
					i.AlphaLevel=1.0
				EndIf	
				i.Update()	
	   End Function	
End Type



'main
While Not KeyHit(KEY_ESCAPE)
	Cls	
	If MouseHit(1) Then
		Image.Create((GraphicsWidth() / 2),(GraphicsHeight() / 2),1.0,1.0)
	EndIf
		
	Image.Render()
		
	Flip()
	FlushMem()
Wend 

Method Update(img:Image) shouldn't have an img parameter.

change ImageList to "List" and put it inside Image

remove "ImageListCount"

Either make Method Render() into a function or take out the loop

Looks like youve missed the point of oop, noofense. Prolly see more changes once these are put in.

No offense taken. That's why I asked.
Now tell me how am I missing the point of OOP.

I'm trying to make sure I didn't have the attitude that I understood OOP when I really didn't.

Bump.

Actually, it looks fine now, its just that it appeared that you were passing img since in a procedural program this is what you would do. Instead, when making methods, you dont pass the object that is being operated on. Also, if you have a function where you pass in a type to modify, particularly if it is a function within a type, it should probably be a method instead.

OK, Thanks!