Fast Line

This code has been declared by its author to be Public Domain code.

Fast Line by Rob Farley

2004

I know this doesnt sound that exciting, however, if you want to draw only vertical and horizonal lines it's a darn sight faster than the standard line function.

I could have locked and unlocked the backbuffer() in the function however, it's much faster to lockbuffer, draw a bunch of lines, then unlockbuffer.

Usage:
fline(x1,y1,x2,y2,r,g,b)

Simple as that... If you try to draw a line that isn't horizontal or vertical it won't do anything.

Example code at the top, all you actually need is the function.

; Fast line, 2004 Rob Farley
; rob@mentalillusion.co.uk

;==========================================================
; example code
;==========================================================

Graphics 640,480
SetBuffer BackBuffer()
LockBuffer BackBuffer()
For x=0 To 200 Step 20
For y=0 To 200 Step 20
fline(0,y,200,y,255,128,0)
fline(x,0,x,200,255,0,0)
Next
Next
UnlockBuffer BackBuffer()
Flip
WaitKey

;==========================================================
; end of example code
;==========================================================


Function fLine(x,y,x1,y1,r=255,g=255,b=255)
; fLine will only draw horizonal or vertical lines, no diagonals
; Defaults to a white line.

argb=(b Or (g Shl 8) Or (r Shl 16) Or ($ff000000))

If x=x1
	If y>y1 Then t=y1:y1=y:y=t
	For n=y To y1
	WritePixelFast x,n,argb,BackBuffer()
	Next
EndIf

If y=y1
	If x>x1 Then t=x1:x1=x:x=t
	For n=x To x1
	WritePixelFast n,y,argb,BackBuffer()
	Next
EndIf 
End Function

Comments

big10p

2004

Is this even faster than Rect for drawing horz/vert lines, then?

Rob Farley

2004

Yes.

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