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Perlin noise: Difference between revisions
Added FORTRAN 90 implementation
(Perlin noise en FreeBASIC) |
(Added FORTRAN 90 implementation) |
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<pre>
0.1369199587840001
</pre>
=={{header|Fortran}}==
{{trans|Java}}
<lang fortran>
PROGRAM PERLIN
IMPLICIT NONE
INTEGER :: i
INTEGER, DIMENSION(0:511) :: p
INTEGER, DIMENSION(0:255), PARAMETER :: permutation = (/151,160,137,91,90,15, &
131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23, &
190, 6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,57,177,33, &
88,237,149,56,87,174,20,125,136,171,168, 68,175,74,165,71,134,139,48,27,166, &
77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244, &
102,143,54, 65,25,63,161, 1,216,80,73,209,76,132,187,208, 89,18,169,200,196, &
135,130,116,188,159,86,164,100,109,198,173,186, 3,64,52,217,226,250,124,123, &
5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,58,17,182,189,28,42, &
223,183,170,213,119,248,152, 2,44,154,163, 70,221,153,101,155,167, 43,172,9, &
129,22,39,253, 19,98,108,110,79,113,224,232,178,185, 112,104,218,246,97,228, &
251,34,242,193,238,210,144,12,191,179,162,241, 81,51,145,235,249,14,239,107, &
49,192,214, 31,181,199,106,157,184, 84,204,176,115,121,50,45,127, 4,150,254, &
138,236,205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180/)
DO i=0, 255
p(i) = permutation(i)
p(256+i) = permutation(i)
END DO
WRITE(*,"(F19.17)") NOISE(3.14d0, 42d0, 7d0)
CONTAINS
DOUBLE PRECISION FUNCTION NOISE(x_in, y_in, z_in)
DOUBLE PRECISION, INTENT(IN) :: x_in, y_in, z_in
DOUBLE PRECISION :: x, y, z
INTEGER :: xx, yy, zz, a, aa, ab, b, ba, bb
DOUBLE PRECISION :: u, v, w
x = x_in
y = y_in
z = z_in
xx = IAND(FLOOR(x), 255)
yy = IAND(FLOOR(y), 255)
zz = IAND(FLOOR(z), 255)
x = x - FLOOR(x)
y = y - FLOOR(y)
z = z - FLOOR(z)
u = FADE(x)
v = FADE(y)
w = FADE(z)
a = p(xx) + yy
aa = p(a) + zz
ab = p(a+1) + zz
b = p(xx+1) + yy
ba = p(b) + zz
bb = p(b+1) + zz
NOISE = LERP(w, LERP(v, LERP(u, GRAD(p(aa), x, y, z), &
GRAD(p(ba), x-1, y, z)), &
LERP(u, GRAD(p(ab), x, y-1, z), &
GRAD(p(bb), x-1, y-1, z))), &
LERP(v, LERP(u, GRAD(p(aa+1), x, y, z-1), &
GRAD(p(ba+1), x-1, y, z-1)), &
LERP(u, GRAD(p(ab+1), x, y-1, z-1), &
GRAD(p(bb+1), x-1, y-1, z-1))))
END FUNCTION
DOUBLE PRECISION FUNCTION FADE(t)
DOUBLE PRECISION, INTENT(IN) :: t
FADE = t ** 3 * (t * ( t * 6 - 15) + 10)
END FUNCTION
DOUBLE PRECISION FUNCTION LERP(t, a, b)
DOUBLE PRECISION, INTENT(IN) :: t, a, b
LERP = a + t * (b - a)
END FUNCTION
DOUBLE PRECISION FUNCTION GRAD(hash, x, y, z)
INTEGER, INTENT(IN) :: hash
DOUBLE PRECISION, INTENT(IN) :: x, y, z
INTEGER :: h
DOUBLE PRECISION :: u, v
h = IAND(hash, 15)
u = MERGE(x, y, h < 8)
v = MERGE(y, MERGE(x, z, h == 12 .OR. h == 14), h < 4)
GRAD = MERGE(u, -u, IAND(h, 1) == 0) + MERGE(v, -v, IAND(h, 2) == 0)
END FUNCTION
END PROGRAM
</lang>
{{out}}
<pre>
0.13691995878400012
</pre>
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