Documentation/figures/4S+2D_reciproque3.pov

   1 #include "colors.inc"    // The include files contain
   2 #include "textures.inc"  // pre-defined scene elements
   3 #include "glass.inc"
   4 #include "metals.inc"
   5 #include "skies.inc"
   6 #include "shapes.inc"
   7 #include "bravais.inc"
   8 #include "arrows.inc"
   9
  10 // the cristal lattice
  11 #declare a = <1,0,0>;
  12 #declare b = <.31,.95,0>;
  13 #declare c = <.4,.5,0.76>;
  14
  15 #declare camera_location = 5 * (x+y+.5*z)+ 3*z + y;
  16 #declare camera_look_at = <0,0,0>+3*z + y;
  17
  18 //#declare camera_location = a/2+b/1.5-2*z;
  19 //#declare camera_look_at = a/2+b/1.5;
  20
  21 global_settings{ max_trace_level 255 }
  22
  23 background { color DarkGreen }
  24
  25 // all setup
  26 camera {
  27   orthographic
  28   location camera_location
  29   look_at camera_look_at
  30 }
  31
  32 light_source {
  33         <10, 0, 0>
  34         color White
  35         parallel
  36         point_at <0, 0, 0>
  37         shadowless
  38 }
  39 light_source {
  40         <0, 10, 0>
  41         color White
  42         parallel
  43         point_at <0, 0, 0>
  44 }
  45 light_source {
  46         <0, 0, 10>
  47         color White
  48         parallel
  49         point_at <0, 0, 0>
  50 }
  51
  52 union{
  53   plane { <1,0,0>, -3 pigment {color LightWood} }
  54   plane { <0,1,0>, 0 pigment {color LightWood*.9 transmit .3} }
  55   plane { <0,0,1>, 0 pigment {color LightWood*.8 transmit .3}}
  56 }
  57
  58 // the tree principals directions
  59 cylinder{<0,0,-10>,<0,0,10>, .01 pigment {color Grey}}
  60 cylinder{<0,-10,0>,<0,10,0>, .01 pigment {color Grey}}
  61 cylinder{<-10,0,0>,<10,0,0>, .01 pigment {color Grey}}
  62
  63 // the Ewald construction
  64 #macro ewald(ki, gamma, delta, Alpha, phi)
  65   #local kf=vrotate(vrotate(ki, delta*x), -gamma*y);
  66   #local Q=kf-ki;
  67   #local n = vrotate(vrotate(vlength(Q)*x, Alpha*y), phi*z);
  68
  69   // plot the ki and kf vectors
  70   union{
  71     arrow(ki, Blue)
  72     arrow(kf, Green)
  73
  74     // angle 2theta
  75     //object{sector(ki,kf, Yellow, .2) no_shadow}
  76
  77     // angle delta
  78     //object{sector(kf, kf.x*x+kf.z*z, Red, .6) no_shadow}
  79     // angle gamma
  80     //object{sector(ki, kf.x*x+kf.z*z, Blue, .6) no_shadow}
  81     translate -ki
  82   }
  83
  84   // the diffraction vector Q
  85   arrow(Q, Red)
  86
  87   // angle vartheta
  88   //object{secteur(x, Q.x*x+Q.y*y, Magenta, .5)}
  89
  90   // angle tau
  91   object{sector(Q, n, ForestGreen, .5) no_shadow}
  92
  93   // angle psi
  94   object{arrow_circular(Q, .5, .05, 0, 90, 1, Red) translate 1.1*Q no_shadow}
  95
  96   arrow(n, Yellow)
  97   //disc {0, vcross(ki, Q), vlength(Q) pigment{color Red+Blue transmit .1}}
  98   disc {0, Q, vlength(Q) pigment{color Red transmit .3}}
  99   //plane { <0,0,-1>, 0 pigment {color LightWood*.2 transmit .7} }
 100
 101   // sphères d'ewald
 102   merge{
 103     sphere{0, vlength(Q) pigment {color Blue transmit .73}}
 104     sphere{-ki, vlength(ki) pigment {color Green transmit .93}}
 105     no_shadow
 106   }
 107 #end
 108
 109 ewald(-3*z, -30, 40, -60, 30)
 110
 111 // Repère orthonormé de la ligne cristal de soleil.
 112 object{repere_soleil translate 7.5*z no_shadow}