Types within Type

BlitzPlus Forums/BlitzPlus Tutorials/Types within Type

superStruct

(Posted 2010) [#1]

How to create a hierarchy of types in BlitzPlus

superStruct

(Posted 2010) [#2]

I was really stuck on this problem one night. Finally, I was just screwing around when I got lucky and struck proverbial gold. I was writing a program to keep track of grades and I needed to create assessments in classes. Here's how I did it.

Type assessment
	Field name
End Type

Type Class
	Field name$
	Field assessment.assessment
End Type

For i = 1 To 10
	class.class = New class
	class\name = "Class" + i
	class\assessment = New assessment
	class\assessment\name = i
Next

For class.class = Each class
	Print class\name
	Print class\assessment\name
Next

waitkey

Stamm

(Posted 2010) [#3]

That one could be very useful by making possible a better aorganisation within Type

deload

(Posted 2015) [#4]

I tried this:

Type Vector3D
	Field x#=0.0
	Field y#=0.0
	Field z#=0.0
End Type

Type Player
	Field uType = 0
	Field uState = 0
	Field uPosition.Vector3D
	Field uV.Vector3D
	Field uA.Vector3D
	Field uF.Vector3D
	Field uJump = 0
	Field uFall = 0
	Field uAction1 = 0
	Field uAction2 = 0
	Field uAction3 = 0
End Type

Function MainLoop()
	SetBuffer BackBuffer()
	Repeat
		Cls
		MovePlayer()
		If KeyHit(1)
			End
		EndIf
		DrawImage player,vPlayer\uPosition\x,vPlayer\uPosition\x
		Flip
	Forever
End Function

Function MovePlayer()
	If JoyY(0) = "-1.52588e-005"
		jSigY = 0
	Else
		jSigY = JoyY(0)
	End If
	
	If (vPlayer\uPosition\x + (jSigX * joyFactor)) < 0
		vPlayer\uPosition\x=1
	Else If (vPlayer\uPosition\x + (jSigX * joyFactor))+ImageWidth(player) >= GraphicsWidth()
		vPlayer\uPosition\x = GraphicsWidth()-ImageWidth(player)
	Else
		vPlayer\uPosition\x = vPlayer\uPosition\x + (jSigX * joyFactor)
	End If
	
	If velocityY < velocityMax
		velocityY = velocityY + acceleration
	End If
	
	If jSigY<0 And (velocityY > -velocityMax)
		velocityY = (-velocityY)
	End If 
	
	If (vPlayer\uPosition\y + (velocityY)) < 0
		vPlayer\uPosition\y = 1
	Else If (vPlayer\uPosition\y + (velocityY))+ImageHeight(player) >= GraphicsHeight()
		vPlayer\uPosition\y = GraphicsHeight()-ImageHeight(player)
	Else
		vPlayer\uPosition\y = vPlayer\uPosition\y + velocityY
	End If
End Function

No syntax errors but the code instantly crashes at runtime on Win7.
Maybe that´s already enough to meet the limits of "You better don´t use types with large numbers of objects".

deload

(Posted 2015) [#5]

Self correction:
You have to initialize the types within a type correctly. It was not sufficient to create a "new Player" but you also have to initialize the field values inside the type if they are custom types themselves.
After modifying the following code my little game ran flawlessly:

Global vPlayer.Player = New Player
vPlayer\uPosition = New Vector3D
vPlayer\uV = New Vector3D
vPlayer\uA = New Vector3D
vPlayer\uF = New Vector3D