[bb] Fast Line by Rob Farley [ 1+ years ago ]

[BlitzBot]

Title : Fast Line
Author : Rob Farley
Posted : 1+ years ago

Description : 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.

Code :

Code: BlitzBasic

1. ; Fast line, 2004 Rob Farley
2. ; rob@mentalillusion.co.uk
3.  
4. ;==========================================================
5. ; example code
6. ;==========================================================
7.  
8. Graphics 640,480
9. SetBuffer BackBuffer()
10. LockBuffer BackBuffer()
11. For x=0 To 200 Step 20
12. For y=0 To 200 Step 20
13. fline(0,y,200,y,255,128,0)
14. fline(x,0,x,200,255,0,0)
15. Next
16. Next
17. UnlockBuffer BackBuffer()
18. Flip
19. WaitKey
20.  
21. ;==========================================================
22. ; end of example code
23. ;==========================================================
24.  
25.  
26. Function fLine(x,y,x1,y1,r=255,g=255,b=255)
27. ; fLine will only draw horizonal or vertical lines, no diagonals
28. ; Defaults to a white line.
29.  
30. argb=(b Or (g Shl 8) Or (r Shl 16) Or ($ff000000))
31.  
32. If x=x1
33.         If y>y1 Then t=y1:y1=y:y=t
34.         For n=y To y1
35.         WritePixelFast x,n,argb,BackBuffer()
36.         Next
37. EndIf
38.  
39. If y=y1
40.         If x>x1 Then t=x1:x1=x:x=t
41.         For n=x To x1
42.         WritePixelFast n,y,argb,BackBuffer()
43.         Next
44. EndIf
45. End Function

Comments :


big10p(Posted 1+ years ago)

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


Rob Farley(Posted 1+ years ago)

 Yes.