aparler/RosettaCodeData
1
0
Fork 0
Code Issues 12 Pull requests 3 Projects Releases Packages Wiki Activity Actions

Just another update

Browse source
This commit is contained in:
Ingy döt Net 2015-02-20 00:35:01 -05:00
parent a25938f123
commit 00a190b0a6
6591 changed files with 94363 additions and 23227 deletions
Download patch file Download diff file Expand all files Collapse all files

32
Task/Bitmap-Bresenhams-line-algorithm/Common-Lisp/bitmap-bresenhams-line-algorithm.lisp
View file

@ -3,26 +3,26 @@
(declare (type integer x1 y1 x2 y2))
(declare (type rgb-pixel pixel))
(let* ((dist-x (abs (- x1 x2)))
(dist-y (abs (- y1 y2)))
(steep (> dist-y dist-x)))
(dist-y (abs (- y1 y2)))
(steep (> dist-y dist-x)))
(when steep
(psetf x1 y1 y1 x1
x2 y2 y2 x2))
x2 y2 y2 x2))
(when (> x1 x2)
(psetf x1 x2 x2 x1
y1 y2 y2 y1))
y1 y2 y2 y1))
(let* ((delta-x (- x2 x1))
(delta-y (abs (- y1 y2)))
(error (floor delta-x 2))
(y-step (if (< y1 y2) 1 -1))
(y y1))
(delta-y (abs (- y1 y2)))
(error (floor delta-x 2))
(y-step (if (< y1 y2) 1 -1))
(y y1))
(loop
:for x :upfrom x1 :to x2
:do (progn (if steep
(setf (rgb-pixel buffer x y) pixel)
(setf (rgb-pixel buffer y x) pixel))
(setf error (- error delta-y))
(when (< error 0)
(incf y y-step)
(incf error delta-x)))))
:for x :upfrom x1 :to x2
:do (if steep
(setf (rgb-pixel buffer x y) pixel)
(setf (rgb-pixel buffer y x) pixel))
(setf error (- error delta-y))
(when (< error 0)
(incf y y-step)
(incf error delta-x))))
buffer))