113 lines
2.7 KiB
Fortran
113 lines
2.7 KiB
Fortran
module fraktals
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implicit none
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contains
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!-----------------------------------------------------
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subroutine simple_julia(pic, cx, cy, maxiter)
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implicit none
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integer, intent(inout), dimension (:,:) :: pic
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real, intent(in) :: cx, cy
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integer, intent(in) :: maxiter
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integer :: ix, iy, width, height
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real :: fx, fy
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complex :: Z, C
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integer :: iter
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logical :: over_iter
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width = ubound(pic, 1)
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height = ubound(pic, 2)
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C = complex(cx, cy)
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print *, "Const = ", C
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do ix = 1, width
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fx = (float(ix) / (float(width)/4.0) - 2.0)
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do iy = 1, height
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fy = (float(iy) / (float(height)/4.0) - 2.0)
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! ------ traitement du pixel
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iter = 0 ; over_iter = .FALSE.
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Z = complex(fx, fy)
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do while (modulus2(Z) .LT. 4.0)
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Z = (Z * Z) + C
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iter = iter + 1
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if (iter .GE. maxiter) then
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over_iter = .TRUE.
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exit
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endif
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end do
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if (over_iter) then
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pic(ix, iy) = 0
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else
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pic(ix, iy) = iter
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endif
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enddo
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enddo
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end subroutine simple_julia
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!-----------------------------------------------------
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!
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! d'après les pages 91/92 du livre de Roger T Stevens
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! "Fractal programming in C"
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!
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subroutine pickover_0(pic, count)
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implicit none
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integer, intent(inout), dimension (:,:) :: pic
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integer, intent(in) :: count
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double precision :: xa, ya, za, xb, yb, zb
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double precision :: ka, kb, kc, kd
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integer :: i, w, h, px, py
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ka = 2.24 ; kb = 0.43 ; kc = -0.65 ; kd = -2.43
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xa = 0.00 ; ya = 0.00 ; za = 0.0
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w = ubound(pic, 1)
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h = ubound(pic, 2)
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do i=1, count
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xb = sin(ka*ya) - za*cos(kb*xa)
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yb = za*sin(kc*xa) - cos(kd*ya)
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zb = sin(xa)
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px = (xb * (w/4.05)) + (w / 2)
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py = (yb * (h/4.05)) + (h / 2)
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pic(px, py) = 200 ! WARNING COREDUMP
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print *, xb, yb, zb
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xa = xb ; ya = yb ; za = zb
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enddo
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end subroutine pickover_0
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!-----------------------------------------------------
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! -- some support functions --
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!-----------------------------------------------------
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function dist0 (x, y)
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implicit none
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real, intent(in) :: x, y
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real :: dist0
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dist0 = ( x*x + y*y )
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end function
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!-----------------------------------------------------
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function modulus2(pt)
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implicit none
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complex, intent(in) :: pt
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real :: modulus2
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modulus2 = real(pt)*real(pt) + imag(pt)*imag(pt)
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end
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!-----------------------------------------------------
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end module fraktals
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