From 8905cf858bb5f380439c26a9ac032d91d8052a09 Mon Sep 17 00:00:00 2001
From: tth <tth@konrad.lan>
Date: Wed, 16 Feb 2022 00:18:35 +0100
Subject: [PATCH] pickover++

---
 Fraktalism/.gitignore   |  3 +++
 Fraktalism/fraktals.f90 | 19 +++++++++++++------
 Fraktalism/pickover.f90 | 31 +++++++++++++++++++++++++++++++
 Fraktalism/plotpick.sh  | 34 ++++++++++++++++++++++++++++++++++
 4 files changed, 81 insertions(+), 6 deletions(-)
 create mode 100644 Fraktalism/pickover.f90
 create mode 100755 Fraktalism/plotpick.sh

diff --git a/Fraktalism/.gitignore b/Fraktalism/.gitignore
index f75e05b..5a6cb68 100644
--- a/Fraktalism/.gitignore
+++ b/Fraktalism/.gitignore
@@ -4,3 +4,6 @@ pickover
 
 *.pgm
 *.gif
+*.asc
+*.png
+
diff --git a/Fraktalism/fraktals.f90 b/Fraktalism/fraktals.f90
index 866ec55..f379321 100644
--- a/Fraktalism/fraktals.f90
+++ b/Fraktalism/fraktals.f90
@@ -52,9 +52,10 @@ subroutine simple_julia(pic, cx, cy, maxiter)
 
 end subroutine simple_julia
 !-----------------------------------------------------
-!
-!
-!
+! 
+!  d'après les pages 91/92 du livre de Roger T Stevens
+!       "Fractal programming in C"
+! 
 subroutine pickover_0(pic, count)
     implicit none
     integer, intent(inout), dimension (:,:)  ::  pic
@@ -62,12 +63,13 @@ subroutine pickover_0(pic, count)
 
     double precision      :: xa, ya, za, xb, yb, zb
     double precision      :: ka, kb, kc, kd
-    integer               :: i, px, py
+    integer               :: i, w, h, px, py
 
     ka = 2.24 ; kb = 0.43 ; kc = -0.65 ; kd = -2.43
-
     xa = 0.00 ; ya = 0.00 ; za = 0.0
 
+    w  = ubound(pic, 1)
+    h = ubound(pic, 2)
 
     do i=1, count
 
@@ -75,8 +77,13 @@ subroutine pickover_0(pic, count)
       yb = za*sin(kc*xa) - cos(kd*ya)
       zb = sin(xa)
 
-      print *, i, xb, yb, zb
+      px = (xb * (w/4.05)) + (w / 2)
+      py = (yb * (h/4.05)) + (h / 2)
 
+      pic(px, py) = 200              ! WARNING COREDUMP
+
+      print *, xb, yb, zb
+      
       xa = xb ; ya = yb ; za = zb 
 
     enddo
diff --git a/Fraktalism/pickover.f90 b/Fraktalism/pickover.f90
new file mode 100644
index 0000000..8c2fbf2
--- /dev/null
+++ b/Fraktalism/pickover.f90
@@ -0,0 +1,31 @@
+! 
+!    this is the main programm
+! 
+!-----------------------------------------------------
+
+program pickover
+
+    use spitpgm
+    use fraktals
+
+    implicit none
+
+    integer, dimension(800, 600)    ::    picz
+    integer                         ::    argc
+    character(200)                  ::    filename
+
+    argc = IARGC()
+    if (1 .NE. argc) then
+      STOP ": PICKOVER NEED A FILENAME !"
+    endif
+
+    call getarg(1, filename)
+
+    write (0, "(A)") "Pickover -> "//trim(filename)
+
+    call pickover_0(picz, 50000)
+    call spit_as_pgm_8(picz, trim(filename))
+
+end program
+
+!-----------------------------------------------------
diff --git a/Fraktalism/plotpick.sh b/Fraktalism/plotpick.sh
new file mode 100755
index 0000000..062cdb5
--- /dev/null
+++ b/Fraktalism/plotpick.sh
@@ -0,0 +1,34 @@
+#!/bin/bash
+
+ASCFILE="nuage.asc"
+IMAGE="pick3d.png"
+
+make pickover
+if [ $? -ne 0 ] ; then
+	echo
+	echo "Make error " $?
+	exit 1
+fi
+
+./pickover foo.pgm > $ASCFILE
+if [ $? -ne 0 ] ; then
+	echo
+	echo "Pickover error " $?
+	exit 1
+fi
+
+
+gnuplot << __EOC__
+set term png    size 1024,768
+set output      "${IMAGE}"
+
+set title "3D Pickover"
+
+splot "$ASCFILE" with dots
+
+__EOC__
+
+
+
+
+