type problem (*solved*) - Printable Version

Code:
Function distance (x1 as Integer, y1 as Integer, x2 as Integer, y2 as Integer) as Integer
Dim x as Integer
x=Abs(x1-x2)
Dim y as Integer
y=Abs(y1-y2)
Return x+y
End Function

Dim bresx(0 to 300) as UByte
Dim bresy(0 to 300) as UByte

Function line(X1 as Integer,Y1 as Integer,X2 as Integer,Y2 as Integer) as Integer
'Draws a line of individual pixels from X1,Y1 to X2,Y2 at any angle

Dim dist as Integer
dist=distance(X1,Y1,X2,Y2)
dim bresiter as Integer
For bresiter=0 To dist 
bresx(bresiter)=0
bresy(bresiter)=0
Next

Dim steep as Byte
steep=Abs(Y2-Y1) > Abs(X2-X1)
PRINT AT 1,1 ; PAPER 1 ; INK 0 ; "steep "+STR(steep)
	
If steep =1 Then
Dim Temp as Integer
steep=X1
X1=Y1
Y1=Temp
Temp=X2
X2=Y2
Y2=Temp
End If
	Dim DeltaX as Integer
    DeltaX=Abs(X2-X1)
	Dim DeltaY as Integer
    DeltaY=Abs(Y2-Y1)
	Dim IError as Integer
    IError=0
	Dim DeltaError as Integer
    DeltaError=DeltaY
	Dim x as Integer
    x=X1		'Start at X1,Y1
	Dim y as Integer
    y=Y1		
	Dim XStep as Integer
	Dim YStep as Integer
	If X1<X2 Then 
    XStep=1 
    Else
    XStep=-1
    end if
    If Y1<Y2 Then 
    YStep=1 
    Else
    YStep=-1	'Direction
	end if
    'If Steep Then Plot(Y,X) Else Plot(X,Y)		'Draw
	Dim iter as Integer=1
	
	While x<>X2
	'Print x+" <x "+X2+"<x2"
	'Print "xstep "+XStep
	'x=truncate(x,1)
		x=x+XStep		'Move in X
	'Print x+" <x after adding xstep "+X2+"<x2"
		
		IError=IError+DeltaError		'Add to counter
		If (IError Shl 1)>DeltaX then		'Would it overflow?
		y=y+YStep		'Move in Y
		IError=IError-DeltaX		'Overflow/wrap the counter
		End if
	'	x=truncate(x,1)
	'	y=truncate(y,1)
	'		Print x+" <x after truncating xstep "+X2+"<x2"
	
	If steep then
		bresx(iter)=y
	'	Print bresx[iter]+"<bresx  iter>"+iter
		bresy(iter)=x
	'	Print bresy[iter]+"<bresy  iter>"+iter

	Else
		bresx(iter)=x
	'	Print bresx[iter]+"<bresx  iter>"+iter

		bresy(iter)=y
	'		Print bresy[iter]+"<bresy  iter>"+iter

	End If
		iter=iter+1
		
	If iter>dist then
	Print  "bresenham over distance "+dist
	Return dist
	End If
	'	If Steep Then Plot(Y,X) Else Plot(X,Y)		'Draw
	Wend
	Return dist
End Function

line(0,0,10,5)
for x=0 to 6
    Plot bresx(x),bresy(x)
next