// povray 3.6


// Präzession eines Schwungrads
//
// Am Schwungrad lassen sich die Auswirkungen der Präzession aufzeigen. Ein Kippen
// der Rotationsachse vom Schwungrad ruft senkrecht zur Achse stehende Kräfte hervor.

// Zentrales Element bildet ein Schwungrad. Damit die vielen Vektoren erkennbar sind,
// wird das als transparentes Objekt abgebilet. Eine Änderung des Drehimpulses führt
// zu entsprechenden Kräften.

// Globale Definitionen

// Achsen
// x -> links nach rechts
// y -> von unten nach oben
// z -> tiefe

// Kameraposition
#declare Kameraposition = <10, 15, -28>;


#declare Vektor_Teilung = 1;
// * Vektor_Durchmesser
#declare Vektor_Durchmesser = 0.1;
// * Vektor_Schrift
#declare Vektor_Schrift = "Schrift/DejaVuSans.ttf"

#declare Winkel_Vektor_Radius = 2.5;

global_settings {
   adc_bailout 0.00392157
   assumed_gamma 1.5
   noise_generator 2
   charset utf8
   
}


light_source {
   Kameraposition
   rgb <1.5, 1.5, 1.5>
   shadowless
}

camera {
   //perspective
   orthographic angle  45
   location Kameraposition
   sky <0, 1, 0>
   direction <0, 0, 1>
   right x*image_width/image_height
   up <0, 1, 0>
   look_at <0, 0, 0>
}

/*
camera { // X
   perspective
   location <45, 0, 0>
   sky <0, 1, 0>
   direction <0, 0, 1>
   right <1, 0, 0>
   up <0, 1, 0>
   look_at <0, 5, 0>
}

camera { // Z
   perspective
   location <0, 0, -45>
   sky <0, 1, 0>
   direction <0, 0, 1>
   right <1, 0, 0>
   up <0, 1, 0>
   look_at <0, 5, 0>
}
*/

#include "../baukasten/baukasten.pov"

#include "colors.inc"


// *******
// *
// * MAIN
// *
// *******

// Koordinaten-Achsen
// Schwungrad
// Drehimpuls

#declare x_offset = -2;
#declare y_offset = -1;


object { // Schwungrad
  schwungrad
  translate x * x_offset
  translate y * y_offset
}

/*
//
// Test #1 - Pfeilung
//

object {
  Winkel_Vektor_Komplett(
    <0,0,0>, 60, 0, 0, 0, "X", "1", 1, Bronze )
}

object {
  Winkel_Vektor_Komplett(
    <0,0,0>, 30, 60, 0, 0, "X", "2", 1, Bronze )
}
object {
  Winkel_Vektor_Komplett(
    <0,0,0>, 90, 0, -90, -30, "X", "3", 1, Bronze )
}
*/


//
// Test #2 - Beschriftung
//
/*
object {
  Winkel_Vektor_Komplett(
    <0,0,0>, 60, 0, 0, 0, "X", "1", 1, Bronze )
}

object {
  Winkel_Vektor_Komplett(
    <0,0,0>, 90, 90, 0, 0, "X", "2", 1, Bronze )
}

object {
  Winkel_Vektor_Komplett(
    <0,0,0>, 90, 0, 90, 0, "X", "3", 1, Bronze )
}

object {
  Winkel_Vektor_Komplett(
    <0,0,0>, 60, 0, 90, 90, "X", "4", 1, Bronze )
}
*/

//
// Drehimpuls und Rotation
//

#local Verhaeltnis = 0.5;

#local L_0 = <7,0,0>;
#local L_1 = <7,Verhaeltnis*7,0>;

object {
  Vektor(<x_offset,y_offset,0>, L_0, "L", "0", ForestGreen)
}

object {
  Vektor(<x_offset,y_offset,0>, L_1, "L", "1", ForestGreen)
}

object {
  Vektor_Invert(<x_offset+7,y_offset,0>, <0,Verhaeltnis*7,0>, "ΔL", "", ForestGreen)
}

object {
  Vektor(<x_offset,y_offset,0>, <5.75,0,0>, "ω", "0", SeaGreen)
  scale 1.0001 // Vermeide Glitch
}

object {
  Vektor(<x_offset,y_offset,0>, <5.75,Verhaeltnis*5.75,0>, "ω", "1", SeaGreen)
  scale 1.0001
}

//
// Winkel Δθ
//

object {
#local lAngle = VAngleD(L_0, L_1);
  Winkel_Vektor_Komplett(
    <x_offset,y_offset,0>, lAngle, 0, 0, 0, "Δθ", "", 1, Scarlet )
}



//
// Weitere Vektoren
//

// Bronze

object {
  Vektor(<x_offset+4,y_offset,0>, <0,0,4>, "F", "", Copper)
}

object {
  Vektor(<x_offset-4,y_offset,0>, <0,0,-4>, "-F", "", Copper)
}

object {
  Vektor(<x_offset,y_offset,0>, <0,0,-3>, "Ω", "", Maroon)
}

object {
  Vektor(<x_offset,y_offset,0>, <0,4,0>, "τ", "", DustyRose)
}



//
// Koordinatenachsen
//

object {
  Vektor(<x_offset+7.5,y_offset,0>, <3,0,0>, "y", "", Gray50) // povray x-Achse
}

object {
  Vektor(<x_offset,y_offset+6,0>, <0,3,0>, "z", "", Gray50) // povray y-Achse
//  Vektor_Index(<0,0,0>, <0,5,0>, "L", "0")
}

object {
  Vektor_Invert(<x_offset,y_offset,-6>, <0,0,-3>, "x", "", Gray50) // povray z-Achse
}


//
// Hintergrund
//

// http://www.f-lohmueller.de/pov_tut/backgrnd/p_sky1d.htm
// sky ------------------------------------
sphere{
  <0,0,0>,1 hollow
  texture{
  pigment{
    gradient <0,-1,0>
    color_map{
      [0.0 color White]
      [1.0 color rgb<0.1,0.25,0.75>]
      [0.8 color rgb<0.1,0.25,0.75>]
      }
    } // end pigment
    finish {ambient 1 diffuse 0}
  } // end of texture
  scale 40
  translate x * x_offset
  translate y * y_offset
} // end of sphere -----------------------
 
/* 
sky_sphere{
  pigment{
    gradient <1,1,0> // Hintergrund
    color_map {
      [0   color rgb<1,1,1>         ]//White
      [0.4 color rgb<0.24,0.34,0.56>]//~Navy
      [0.6 color rgb<0.24,0.34,0.56>]//~Navy
      [1.0 color rgb<1,1,1>         ]//White
    }
    scale 2
  }
} // end of sky_sphere
*/
// EOF