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

commit deletes

Browse source
This commit is contained in:
Ingy döt Net 2013-10-27 23:48:49 +00:00
parent 776bba907c
commit 372c577f83
233 changed files with 0 additions and 6724 deletions
Download patch file Download diff file Expand all files Collapse all files

53
Task/Bitmap-Bresenhams-line-algorithm/ALGOL-68/bitmap-bresenhams-line-algorithm.alg
View file

@ -1,53 +0,0 @@
PRAGMAT READ "Basic_bitmap_storage.a68" PRAGMAT;
line OF class image := (REF IMAGE picture, POINT start, stop, PIXEL color)VOID:
BEGIN
REAL dx = ABS (x OF stop - x OF start),
dy = ABS (y OF stop - y OF start);
REAL err;
POINT here := start,
step := (1, 1);
IF x OF start > x OF stop THEN
x OF step := -1
FI;
IF y OF start > y OF stop THEN
y OF step := -1
FI;
IF dx > dy THEN
err := dx / 2;
WHILE x OF here /= x OF stop DO
picture[x OF here, y OF here] := color;
err -:= dy;
IF err < 0 THEN
y OF here +:= y OF step;
err +:= dx
FI;
x OF here +:= x OF step
OD
ELSE
err := dy / 2;
WHILE y OF here /= y OF stop DO
picture[x OF here, y OF here] := color;
err -:= dx;
IF err < 0 THEN
x OF here +:= x OF step;
err +:= dy
FI;
y OF here +:= y OF step
OD
FI;
picture[x OF here, y OF here] := color # ensure dots to be drawn #
END # line #;
###
The test program:
###
IF test THEN
REF IMAGE x = INIT LOC[1:16, 1:16]PIXEL;
(fill OF class image)(x, white OF class image);
(line OF class image)(x, ( 1, 8), ( 8,16), black OF class image);
(line OF class image)(x, ( 8,16), (16, 8), black OF class image);
(line OF class image)(x, (16, 8), ( 8, 1), black OF class image);
(line OF class image)(x, ( 8, 1), ( 1, 8), black OF class image);
(print OF class image)(x)
FI