Qbasicnews.com - Best algorithm for a 2D Perlin Noise ?

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Antoni Gual saying to Jark "it's really fast"... Must be a kind of Spanish virus that crossed the Pyrenean moutains :wink:

Antoni, this virus is dangerous...

Code:
DIM Cloud%(129, 129)

RANDOMIZE TIMER

T0 = TIMER

' Init the corners

Cloud%(1, 1) = 128

Cloud%(1, 129) = 128

Cloud%(129, 1) = 128

Cloud%(129, 129) = 128

' Init the edges

FOR Rank% = 1 TO 7

Grid% = 2 ^ (7 - Rank% + 1)

nStep% = 2 ^ (Rank% - 1) + 1

FOR kx% = 1 TO nStep% - 1

x% = (kx% - 1) * Grid% + 1: y% = 1

Alt% = (Cloud%(x%, y%) + Cloud%(x% + Grid%, y%)) / 2

zNew% = INT(Alt% * (1 + (RND - .5) / (2 ^ Rank%)))

Cloud%(x% + Grid% / 2, 1) = zNew%

Cloud%(x% + Grid% / 2, 129) = zNew%

NEXT kx%

FOR ky% = 1 TO nStep% - 1

x% = 1: y% = (ky% - 1) * Grid% + 1

Alt% = (Cloud%(x%, y%) + Cloud%(x%, y% + Grid%)) / 2

zNew% = INT(Alt% * (1 + (RND - .5) / (2 ^ Rank%)))

Cloud%(1, y% + Grid% / 2) = zNew%

Cloud%(129, y% + Grid% / 2) = zNew%

NEXT ky%

NEXT Rank%

' Fill the clouds

FOR Rank% = 1 TO 7

Grid% = 2 ^ (7 - Rank% + 1)

nStep% = 2 ^ (Rank% - 1) + 1

FOR kx% = 1 TO nStep% - 1

x% = (kx% - 1) * Grid% + 1

FOR ky% = 1 TO nStep% - 1

y% = (ky% - 1) * Grid% + 1

Alt% = (Cloud%(x%, y%) + Cloud%(x% + Grid%, y%) + Cloud%(x%, y% + Grid%) + Cloud%(x% + Grid%, y% + Grid%)) / 4

Cloud%(x% + Grid% / 2, y% + Grid% / 2) = INT(Alt% * (1 + (RND - .5) / (2 ^ Rank%)))

Alt% = (Cloud%(x%, y%) + Cloud%(x% + Grid%, y%)) / 2

IF y% <> 1 THEN Cloud%(x% + Grid% / 2, y%) = INT(Alt% * (1 + (RND - .5) / (2 ^ Rank%)))

Alt% = (Cloud%(x%, y%) + Cloud%(x%, y% + Grid%)) / 2

IF x% <> 1 THEN Cloud%(x%, y% + Grid% / 2) = INT(Alt% * (1 + (RND - .5) / (2 ^ Rank%)))

Alt% = (Cloud%(x% + Grid%, y%) + Cloud%(x% + Grid%, y% + Grid%)) / 2

IF (x% + Grid%) <> 129 THEN Cloud%(x% + Grid%, y% + Grid% / 2) = INT(Alt% * (1 + (RND - .5) / (2 ^ Rank%)))

Alt% = (Cloud%(x%, y% + Grid%) + Cloud%(x% + Grid%, y% + Grid%)) / 2

IF (y% + Grid%) <> 129 THEN Cloud%(x% + Grid% / 2, y% + Grid%) = INT(Alt% * (1 + (RND - .5) / (2 ^ Rank%)))

NEXT ky%

NEXT kx%

NEXT Rank%

dt = TIMER - T0

CLS

PRINT dt

You could also change all

Code:
result= INT(anything/something)

Code:
result=anything\something

Integer division is faster...

Also you could precalculate an array of powers of 2... Big Grin

It's only a sphere, and I don't control everything yet, but that's a beginning...

[Image: Sphere.jpg]

I seriously need to develop an regular antialiasing routine... my smoothering filter only handles black spots.

[Image: Pcube.jpg]

:o :o :o :o :o :o :o :o :o :o :o :o :o

*jaw drops!!!!

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