first Julia set plotted

Fraktalism/fraktals.f90

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+module fraktals
+  implicit none
+  contains
+
+!-----------------------------------------------------
+subroutine simple_julia(pic, cx, cy)
+    implicit none
+    integer, intent(inout), dimension (:,:)  ::  pic
+    real, intent(in)                         ::  cx, cy
+
+    integer      ::  ix, iy, width, height
+    real         ::  fx, fy
+    complex      ::  Z, C
+    integer      ::  iter, maxiter
+
+    width  = ubound(pic, 1)
+    height = ubound(pic, 2)
+    print *, "image size : ", width, height
+    ! print *, "constante  : ", cx, cy
+
+    maxiter = 500
+    C = complex(cx, cy)
+    print *, "C = ", C
+
+    do ix = 1, width
+      fx = (float(ix) / (float(width)/4.0) - 2.0)
+      do iy = 1, height
+        fy = (float(iy) / (float(height)/4.0) - 2.0)
+
+          ! ------ traitement du pixel
+          iter = 0
+          Z = complex(fx, fy)
+          do while ( (modulus2(Z) .LT. 4.0) .AND.     &
+                     (iter < maxiter) )
+            Z = (Z * Z) + C
+            iter = iter + 1
+
+          end do
+
+          pic(ix, iy) = iter
+
+          ! print *, ix, iy, "    ", fx, fy, "    ", iter
+
+      enddo
+    enddo 
+
+end subroutine
+!-----------------------------------------------------
+function dist0 (x, y)
+  implicit none
+  real, intent(in)    :: x, y
+  real                :: dist0
+  dist0 = ( x*x + y*y )
+end function
+
+!-----------------------------------------------------
+function modulus2(pt)
+  implicit none
+  complex, intent(in)    ::   pt
+  real                   ::   modulus2
+  modulus2 = real(pt)*real(pt) + imag(pt)*imag(pt)
+end
+!-----------------------------------------------------
+
+end module fraktals