178 lines
4.4 KiB
Fortran
178 lines
4.4 KiB
Fortran
module fraktals
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use points3d
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implicit none
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!-----------------------------------------------------
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!-----------------------------------------------------
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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 compute_pickover(array, coefs)
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type(t_point3d), dimension(:) :: array
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double precision, dimension(4) :: coefs
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double precision :: xa, ya, za, xb, yb, zb
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integer :: i
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! print *, "coefs ", coefs
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write(0, '(1X, A18, I9)') "compute pickover ", ubound(array, 1)
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xa = 0.00 ; ya = 0.00 ; za = 0.0
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do i=1, ubound(array, 1)
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xb = sin(coefs(1)*ya) - za*cos(coefs(2)*xa)
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yb = za*sin(coefs(3)*xa) - cos(coefs(4)*ya)
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zb = sin(xa)
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array(i)%x = xb
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array(i)%y = yb
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array(i)%z = zb
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array(i)%seq = i
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xa = xb ; ya = yb ; za = zb
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! print *, xb, yb, zb
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enddo
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end subroutine
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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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type(t_point3d), dimension(:), allocatable :: points
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double precision, dimension(4) :: coefs
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integer :: i, w, h, px, py, errcode
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write(0, '(1X, A18 , I9)') "pickover_0 ", count
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allocate(points(count), stat=errcode)
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if (0 .NE. errcode) then
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STOP " : NO ENOUGH MEMORY"
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endif
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coefs(1) = 2.24 ; coefs(2) = 0.43
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coefs(3) = -0.65 ; coefs(4) = -2.43
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call compute_pickover(points, coefs)
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w = ubound(pic, 1)
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h = ubound(pic, 2)
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do i=1, ubound(points, 1)
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px = (points(i)%x * (w/4.09)) + (w / 2)
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py = (points(i)%y * (h/4.09)) + (h / 2)
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pic(px, py) = 255 ! WARNING COREDUMP
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enddo
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deallocate(points)
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end subroutine pickover_0
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!-----------------------------------------------------
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!
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! d'après les pages NN/NN du livre de Roger T Stevens
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! "Fractal programming in C"
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!
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subroutine lorentz_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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! XXX double precision :: xa, ya, za, xb, yb, zb
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! XXX double precision :: ka, kb, kc, kd
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! XXX integer :: i, w, h, px, py
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end subroutine lorentz_0
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!-----------------------------------------------------------
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! -- some support functions --
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!-----------------------------------------------------------
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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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