42 lines
1.2 KiB
Fortran
42 lines
1.2 KiB
Fortran
!
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! BUILD A STAR FIELD
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!
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program starfield
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use genplotting
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implicit none
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write (0, '(A)') "----[ genplotting starfield ]----"
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call genp_init (0, 'WS/starfield.scratch')
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call do_starfield (451)
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call genp_end (0)
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contains
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! ---------------------------------------------------------
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subroutine plot_a_star(at_x, at_y, sz, color)
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real, intent(in) :: at_x, at_y, sz
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integer, intent(in) :: color
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integer :: idx
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real :: rad, xv, yv
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write(0, '("plot a star ", 2F8.3)') at_x, at_y
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call genp_set_offset(at_x, at_y)
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do idx=0, 360, 36
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rad = 0.042 + (real(idx) * (3.14159 / 180))
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xv = sz * sin(rad) ; yv = sz * cos(rad)
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call genp_move(0.0, 0.0)
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call genp_draw(xv, yv, color)
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enddo
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end subroutine
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! ---------------------------------------------------------
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subroutine do_starfield (nbstar)
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integer, intent(in) :: nbstar
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integer idx, color
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real px, py, sz
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do idx=1, nbstar
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px = (rand(0) * 10.00) - 5.00
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py = (rand(0) * 10.00) - 5.00
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sz = (rand(0) * 0.16) + 0.16
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color = 1 + mod(idx, 7)
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call plot_a_star(px, py, sz, color)
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end do
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end subroutine
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! ---------------------------------------------------------
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end program
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