we are on a good way, maybe...

BloubWorld/exportbloubs.f90

@@ -1,4 +1,4 @@
-program genbloubs
+program exportbloubs
 
   use bloubspace
   implicit none

GravityField/.gitignore

@@ -11,7 +11,7 @@ WS/*/*.png
 *.log
 *.mp4
 
-pov.stderr
+*.stderr
 
 foo.pgm
 bar.pgm

GravityField/Makefile

@@ -3,9 +3,9 @@
 #
 
 GFOPT   = -Wall -Wextra -g -time -I../Modules
-MODOBJ  = '../Modules/spitpgm.o'
+MODOBJ  = ../Modules/spitpgm.o
 
-all:	essai
+all:	essai animation
 
 # ----------- modules
 

GravityField/README.md

@@ -1,5 +1,23 @@
-# Gravity Field
+# Gravity Field Experiment
 
-Some crude experiments to make fancy picture of a useless gravaity field.
+_Some crude experiments to make fancy picture of a useless gravity field._
 
 Expect bug party.
+
+## Le module `realfield`
+
+Les mécaniques sous-jacentes. Sans la moindre rigueur mathématique.
+
+## Le commandeur en chef
+
+C'est le logiciel sobrement nommé `animation` qui n'est absolument
+pas fini. Par exemple, il n'est absolument pas paramétrable sans
+passer per une recompilation.
+
+## Le raytracing
+
+Vous vous en doutez, c'est du POVray. 
+
+## Conclusion
+
+Enjoy !

GravityField/animation.f90

@@ -12,15 +12,16 @@ program animation
   ! some configuration constants
   integer, parameter      :: S_WIDTH  = 1024
   integer, parameter      :: S_HEIGHT = 1024
-  integer, parameter      :: NB_BODY  = 150
+  integer, parameter      :: NB_BODY  = 82
 
   !!! WARNING : global variables !!!
   type(massbody)          :: planets(NB_BODY)
-  ! integer                 :: foo
 
   call init_random()
   call create_some_planets(planets, 1337e3, S_WIDTH , S_HEIGHT)
-  call barycentre_bodies(planets)
+  call print_barycentre_bodies(planets)
+
+  ! STOP 'BEFORE CRASH'
 
   call la_grande_boucle(0, 2000, planets)
 
@@ -39,25 +40,37 @@ subroutine la_grande_boucle(start, nbre, moons)
   integer                 :: pass 
 
   do pass=start, start+nbre-1
+    ! if second parameter is TRUE, use clipping,
+    !                     else     use ?????ing
+    call deplace_les_planetes(moons, .TRUE.)
   
     write (filename, "(a, i5.5, a)") 'WS/nanim/', pass, '.pgm'
-    write(0, *) filename
+    write(0, '(3I5, "    *  ", a20)') start, nbre, pass, filename
-
     call build_and_write_a_field(S_WIDTH, S_HEIGHT, moons, filename)
-
-    call deplace_les_planetes(moons)
-
   enddo
 
+call print_barycentre_bodies(moons)
+
 end subroutine
 
 !-----------------------------------------------------------------------
-subroutine deplace_les_planetes(moons)
+!-
+!     C'est ici que se passe le deplacement des choses mouvantes
+!-
+!     Il y a deux manieres d'aborder les bords de l'univers (non, le combo
+!     segfault/coredump n'en fait pas partie).
+!-
+subroutine deplace_les_planetes(moons, clipit)
   type(massbody), intent(inout)    :: moons(:)
+  logical, intent(in)              :: clipit
 
   integer                 :: foo
   real                    :: depx, depy
 
+  integer, parameter      :: EE = 45
+  integer                 :: SW = S_WIDTH  - EE
+  integer                 :: SH = S_HEIGHT - EE
+
   do foo=1, ubound(moons, 1)
 
     ! print *, "----- deplace ",foo, "serial ", moons(foo)%serial
@@ -68,15 +81,24 @@ subroutine deplace_les_planetes(moons)
 
     !-
     !   ici se pose une question pertinente sur la gestion des
-    !   bords du chanmp. Cclippin or Boucing ?
+    !   bords du chanmp. Clipping, Toring or Boucing ?
     !-
-    if (moons(foo)%posx .GT. S_WIDTH)   moons(foo)%posx = 0.0
+    if (clipit) then
-    if (moons(foo)%posy .GT. S_HEIGHT)  moons(foo)%posy = 0.0
+      if (moons(foo)%posx .GT. SW)     moons(foo)%posx = SW
-    if (moons(foo)%posx .LT. 0)         moons(foo)%posx = S_WIDTH
+      if (moons(foo)%posy .GT. SH)     moons(foo)%posy = SH
-    if (moons(foo)%posy .LT. 0)         moons(foo)%posy = S_HEIGHT
+      if (moons(foo)%posx .LT. EE)     moons(foo)%posx = EE
+      if (moons(foo)%posy .LT. EE)     moons(foo)%posy = EE
+      ! STOP 'BECAUSE WE ARE TOTALY FUCKED'
+    else
+      if (moons(foo)%posx .GT. SW)     moons(foo)%posx = EE
+      if (moons(foo)%posy .GT. SH)     moons(foo)%posy = EE
+      if (moons(foo)%posx .LT. EE)     moons(foo)%posx = SW
+      if (moons(foo)%posy .LT. EE)     moons(foo)%posy = SH
+    endif
 
-    moons(foo)%heading = moons(foo)%heading + (0.08*rand())
+    moons(foo)%heading = moons(foo)%heading + (0.25*(rand()-0.499999))
     if (moons(foo)%heading .GT. 6.2831853) moons(foo)%heading = 0.0
+    if (moons(foo)%heading .LT. 0.0000001) moons(foo)%heading = 0.0
 
   enddo
 

GravityField/encode.sh

@@ -27,7 +27,7 @@ case  $filetype in
 esac
 echo "extension  :" $extension
 
-TITLE='---{ experimental gravity field }---'
+TITLE=$(printf -- '---{ experimental gravity field %d }---' $$)
 
 ffmpeg  -nostdin					\
 	-loglevel warning				\
@@ -37,6 +37,6 @@ ffmpeg  -nostdin					\
 	-c:v libx264 -pix_fmt yuv420p			\
 	$FNAME
 
-echo
+echo $FNAME ' ..... [done]'
 
 

GravityField/raytrace.sh

@@ -2,16 +2,20 @@
 
 set -e
 
-POVOPT=" -q9 +a -W1280 -H1024 +WT2 -d -v "
+POVOPT=" -q9 +a -W1024 -H768 +WT2 -d -v "
 SOURCE="vision.pov"
 TMPF="/dev/shm/gravfield.png"
 
+date > pov.stderr
+
 #		---------------------------------------
 
 une_passe ()
 {
 clock=$1
 
+cp pov.stderr old.stderr
+
 povray -i${SOURCE} -K${clock} $POVOPT -O${TMPF} 2> pov.stderr
 
 timestamp=$(date -u +'%F %H:%M' | tr '01' 'Ol')
@@ -20,14 +24,14 @@ outfile=$(printf "WS/troid/%05d.png" $clock)
 echo  $timestamp $texte $outfile
 
 convert	${TMPF}				\
-	-pointsize 16			\
+	-pointsize 24			\
 	-font Courier-Bold		\
 	-fill Orange			\
-	-annotate +10+16  "$timestamp"	\
+	-annotate +15+16  "$timestamp"	\
-	-annotate +10+34  "$texte"	\
+	-annotate +15+38  "$texte"	\
-	-pointsize 8			\
+	-pointsize 16			\
 	-gravity south-west		\
-	-annotate +10+6 "tTh & Konrad"	\
+	-annotate +15+6 "tTh & Konrad"	\
 	${outfile}
 }
 
@@ -37,12 +41,11 @@ for foo in $(seq 0 1999)
 do
 	echo '............' $foo
 	une_passe $foo
-	exit
 done
 
 ffmpeg  -nostdin					\
 	-loglevel warning				\
-	-y -r 30 -f image2 -i WS/trid/%05d.png 		\
+	-y -r 30 -f image2 -i WS/troid/%05d.png 	\
 	-metadata artist='---{ tTh and Konrad }---'	\
 	-metadata title="Experiment on Gravity Field"	\
 	-c:v libx264 -pix_fmt yuv420p			\

GravityField/realfield.f90

@@ -9,11 +9,12 @@ module realfield
   implicit none
 
 !-----------------------------------------------------------------------
+!-
 !      definition of structures
 !-
 type massbody
-  real                  :: posx, posy
+  real                  :: posx = 0, posy = 0
-  real                  :: heading       = 0.21
+  real                  :: heading       = 0.29
   real                  :: speed         = 1.017
   real                  :: mass          = 1.0
   integer               :: serial        = 666
@@ -22,63 +23,76 @@ end type
 !-----------------------------------------------------------------------
 contains
 !-----------------------------------------------------------------------
-subroutine barycentre_bodies(astres)
+subroutine compute_barycentre_bodies(astres, bcx, bcy)
   type(massbody), intent(in)     :: astres(:)
-
+  real, intent(out)              :: bcx, bcy
-  real                           :: cx, cy
   integer                        :: foo
+  real                           :: cx, cy
 
-  !-
   !   May be we have to use DOUBLE RPECSION here ?
-  !-
   cx = 0.0
   cy = 0.0
   do foo=1, ubound(astres, 1)
     cx = cx + astres(foo)%posx
     cy = cy + astres(foo)%posy
   enddo
-  cx = cx / real(ubound(astres, 1))
+  bcx = cx / real(ubound(astres, 1))
-  cy = cy / real(ubound(astres, 1))
+  bcy = cy / real(ubound(astres, 1))
-  print *, 'barycentre:', cx, cy
+end subroutine
+!-----------------------------------------------------------------------
+subroutine print_barycentre_bodies(astres)
+  type(massbody), intent(in)     :: astres(:)
+  real                           :: cx, cy
+
+  call compute_barycentre_bodies(astres, cx, cy)
+  print *, "barycentre :   ", cx, cy
 
 end subroutine
 !-----------------------------------------------------------------------
 !-
 !              make a few solid body to play with...
 !-     
+!       planets    :   an array of type(massbody) to be filled
+!       coef       :   for setting the mass of the body
+!       sx, sy     :   borders of the universe
+!-
 subroutine create_some_planets(planets, coef, sx, sy)
   type(massbody), intent(inout)     :: planets(:)
   real, intent(in)                  :: coef
   integer, intent(in)               :: sx, sy
-
   integer                           :: foo
   character(100)                    :: fmt
 
   fmt = "(I4, '  | ', 2(F10.2, '  '), ' | ', 2F9.3, '  ', e12.3, I7)"
 
   do foo=1, ubound(planets, 1)
+    if (foo .EQ. 1) then
       !-
       !   the first planet is the home of Johnny Root
       !-
-    if (foo .EQ. 1) then
       planets(1)%posx   = sx / 2
       planets(1)%posy   = sy / 2
-      planets(1)%mass   = 37e8
+      planets(1)%mass   = 29e8
       planets(1)%serial = 1337
+      planets(1)%speed  = 6.666
     else
+      !-
+      !   others are planets for peones
+      !-
       planets(foo)%posx     = rand() * real(sx-1)
       planets(foo)%posy     = rand() * real(sy-1)
       planets(foo)%mass     = 7e6 + coef*foo
       planets(foo)%heading  = 3.14159 * rand()
-      if (rand() .LT. 0.01) planets(foo)%speed = 2.718
+      if (rand() .LT. 0.08) planets(foo)%speed = 3.14159
       planets(foo)%serial   = foo*2 + 120
     endif
     write (*, fmt) foo, planets(foo)
   enddo
-
 end subroutine
 !-----------------------------------------------------------------------
-
+!-
+!           the basis of the kluge
+!-
 function compute_gravity(fx, fy, body)
   real, intent(in)              :: fx, fy
   type(massbody), intent(in)    :: body
@@ -88,7 +102,7 @@ function compute_gravity(fx, fy, body)
   rx = fx - body%posx
   ry = fy - body%posy
   dist = sqrt( (rx*rx) + (ry*ry) )
-  if (dist .LT. 0.11) then
+  if (dist .LT. 0.08) then
     ! write (0, *) "dist too small ", dist
     compute_gravity = 0e0
   else

GravityField/runme.sh

@@ -2,9 +2,9 @@
 
 set -e				# stop on error
 
-make essai
+make animation
 
-time ./essai | tee essai.log
+time ./animation | tee animation.log
 
-./encode.sh WS/field/ foo.mp4
+./encode.sh WS/nanim/ quux.mp4
 

GravityField/vision.pov

@@ -14,6 +14,7 @@ global_settings {
 #include  "colors.inc"
 
 #declare NormClock = clock / 2000.01;
+#debug concat("- - - - - - - ", str(NormClock, 7, 5), "\n")
 
 // ----------------------------------------------------------------------
 
@@ -35,11 +36,17 @@ texture {
 	}
 }
 
-object { GravityField scale <4, 0.70, 4> }
+object { GravityField scale <4, 0.60, 4> }
 
 // ----------------------------------------------------------------------
 
-cylinder { <0, -0.5, 0>, <0, 1, 0>, 0.0175 pigment { color Red } }
+/* XXX
+merge {
+	cylinder { <0, -0.5, 0>, <0, 1, 0>, 0.0175  }
+	sphere   { <0, 1, 0>, 0.0175  }
+	pigment { color Red }
+	}
+XXX */
 
 light_source { < -2, 9.3, -7>	color Gray90			}
 light_source { < -6, 9.3, -8>	color Orange*0.75		}
@@ -48,10 +55,10 @@ light_source { < -15, 2.3, 17>	color Green*0.25			}
 // ----------------------------------------------------------------------
 
 camera	{
-	location	<-8, 4-NormClock, 1 + 3*NormClock>
+	location	<-8, 4-NormClock, 1 + (5*NormClock)>
 	look_at		<0, 0, 0>
 	right		x*image_width/image_height
-	angle		34
+	angle		33
 	}
 
 // ----------------------------------------------------------------------