Q1: best way to cleanup types?

Blitz3D Forums/Blitz3D Beginners Area/Q1: best way to cleanup types?

keyboard

(Posted 2003) [#1]

I wonder what is the best way to cleanup types at the end of their use.

I see this example:

For My.NewType = Each NewType
	Delete My
Next

but what if one of the type fields is a handle for an image?
Should it be deleted with freeimage, or is it sufficient to delete each instance of the type, as above?

thanks

GitTech

(Posted 2003) [#2]

Should it be deleted with freeimage,

Yep :)

Bremer

(Posted 2003) [#3]

delete each newtype

that should delete all types of that name

GitTech

(Posted 2003) [#4]

delete each newtype

that should delete all types of that name

But it won't free images/entities that are stored in them.

_PJ_	(Posted 2003) [#5]

For My.NewType = Each NewType

(provided you know that My\Mesh is the handle for meses etc)

For My.NewType = Each NewType
If My\Mesh>0
FreeEntity My\Mesh
EndIf
Delete My
Next

BlitzSupport

(Posted 2003) [#6]

Yeah, you must free any images, sounds, etc, stored in your types, so Malice's code would be necessary there, whereas if it's just a bunch of variables that don't point to any resources you can just 'Delete Each Your_Type'...

keyboard

(Posted 2003) [#7]

Ok, so Like Malice's code I would do:


Type SpriteType
	Field graphic
	Field X#
	Field Y#
End Type

For i% = 1 To 100 step 10
	My.SpriteType = New SpriteType	
	My\graphic = Spritepic
	My\X# = 0 + i%
	My\Y# = 0
Next

;stuff

For	My.SpriteType = Each SpriteType
	FreeImage My\graphic
	Delete My
Next

I think that is right!

jhocking

(Posted 2003) [#8]

You just have to realize that the handle for an image, such as a field in a type, is just an integer which stores the memory address for the image, NOT the image data itself. If you say handle=LoadImage("image.bmp") "handle" is just a number. Similarly, writing My\graphic=LoadImage("image.bmp") just puts a number in "My\graphic." When you delete a type you are just removing the number.

Note that there are certain commands which wipe all graphics from memory so when you do that you don't have to deliberately free the graphics. For example, for 3D graphics you just call ClearWorld and then Delete Each [type.]

keyboard

(Posted 2003) [#9]

Thanks Joe, so in that case, this would be OK?


Spritepic = LoadImage("data/gfx/dodgy_graphic.png")

Type SpriteType
	Field graphic
	Field X#
	Field Y#
End Type

For i% = 1 To 100 step 10
	My.SpriteType = New SpriteType	
	My\graphic = Spritepic
	My\X# = 0 + i%
	My\Y# = 0
Next

;stuff

For	My.SpriteType = Each SpriteType	
	Delete My
Next

FreeImage Spritepic

just to be painfully clear and your patience is appreciated...

Foppy

(Posted 2003) [#10]

It can be handy to write functions to do this, like this:

Type SPRITE
   Field f_image
End Type

Function SPRITE_delete(p_sprite.SPRITE)
   FreeImage(p_sprite\f_image)
   Delete(p_sprite)
End Function

Function SPRITE_deleteAll()
   For sprite.SPRITE = Each SPRITE
      SPRITE_delete(sprite)
   Next
End Function

; at the end of your program or level you can now say:

SPRITE_deleteAll()

This may look like extra work, but when you do it like this you assure that what needs to be done is done (when you put it in the function) upon deletion of an object. For instance, suppose you want to keep track of the number of sprites objects. You could add an extra line to the delete function like this:

; suppose this is the global sprite counter
g_spriteCounter = 0

Function SPRITE_delete(p_sprite.SPRITE)
   FreeImage(p_sprite\f_image)
   Delete(p_sprite)
   g_spriteCounter = g_spriteCounter - 1
End Function