[MacOS] How to copy NSPoint struct into a type

BlitzMax Forums/BlitzMax Programming/[MacOS] How to copy NSPoint struct into a type

d-bug

(Posted 2014) [#1]

Hello folks,

how do I have to copy a NSPoint struct into a BlitzMax type? The following sample should illustrate what I've done so far.

SuperStrict

Import pub.macos

Extern
	Function _PointFromString:Int(a:Int) = "NSPointFromString"
	Function _UserName:Int() = "NSUserName"
End Extern

'NSPoint struct
Type NSPoint
	Field x:Float
	Field y:Float
End Type

Function NSPointFromString:NSPoint(value:String)
	Local pt:Int = _PointFromString(NSStringFromBBString(value))
	Local res:NSPoint = New NSPoint
	MemCopy(Byte Ptr(res), Byte Ptr(pt), SizeOf(res)) '<-- EXC_BAD_ACCESS and KERN_INVALID_ADDRESS
	Return res
End Function

Function NSUserName:String()
	Return bbStringFromNSString(_userName())
End Function

'testing NSUserName... 
Local userName:String = NSUserName()
Print ("-> "+userName)

'testing NSPointFromString...
Local point:NSPoint = NSPointFromString("{100, 500}")
Print("-> "+point.x+","+point.y)

While NSUserName passed the test and prints my username to the output panel, NSPointFromString crashes on MemCopy with a EXC_BAD_ACCESS and KERN_INVALID_ADDRESS error.

I'm not very experienced with C interfaces, so I'm stuck at this point.