Summary edit

Licensing edit

I, the copyright holder of this work, hereby publish it under the following license:

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled GNU Free Documentation License.http://www.gnu.org/copyleft/fdl.htmlGFDLGNU Free Documentation Licensetruetrue

	This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license.
	You are free: to share – to copy, distribute and transmit the work to remix – to adapt the work Under the following conditions: attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use. share alike – If you remix, transform, or build upon the material, you must distribute your contributions under the same or compatible license as the original.
	This licensing tag was added to this file as part of the GFDL licensing update.http://creativecommons.org/licenses/by-sa/3.0/CC BY-SA 3.0Creative Commons Attribution-Share Alike 3.0truetrue

POV-Ray code edit

Below is the code to render this image using the Persistence of Vision Raytacer:

/*
================================================
Ferromagnetism and orthomagnetism
------------------------------------------------
Created by Søren Peo Pedersen - see my user page
at http://da.wikipedia.org/wiki/Bruger:Peo
================================================
*/

#declare MagnetFont="arialbd.ttf" // Font for the nomenclature on magnets
#declare NorthLtr="N";  // Letter to indicate north pole
#declare SouthLtr="S";  // Letter to indicate south pole

#declare ArrowHead=difference { // Head on arrows on sides of sample blocks:
  box {<0,-1,0>,<1,1,1> rotate <0,45,0> scale <4,1,1> translate <-.9,0,0>}
  plane {<-1,0,0>,.6}
  }

#declare DoubleArrow=merge {    // Define one complete double arrow
  box {<-.6,-1,-.015>,<.6,1,.015>}
  #object {ArrowHead}
  #object {ArrowHead scale <-1,1,1>}  
  }

#declare ArrowSet=merge {       // Declare a complete set of arrows
  #object {DoubleArrow translate <0,0,.3>}
  #object {DoubleArrow translate <0,0,-.3>}
  #object {DoubleArrow rotate <90,0,0>}
  }

#declare MagnetPair=union {   // One pair of a N and S magnetic pole
  // The magnet at the left-hand side of the image:
  box {<-15,-1,-1>,<-3,1,1> // A box shape
    pigment {
      object {
        text {ttf MagnetFont,NorthLtr,3,0 //... with letter for "north" on it
          scale 2 translate <-4.3,-.7,-1.5>
          }
        color rgb <1,0,0>
        color rgb .85
        }
      }
    finish {ambient .4}
    no_shadow
    no_reflection
    }
  // The magnet at the right-hand side of the image:
  box {<3,-1,-1>,<15,1,1> // A box shape
    pigment {
      object {
        text {ttf MagnetFont,SouthLtr,3,0 // ... with letter for "south" on it
          scale 2 translate <3.2,-.7,-1.5>
          }
        color rgb .85
        color rgb <1,0,0>
        }
      }
    finish {ambient .4}
    no_shadow
    no_reflection
    }
  }

#declare SampleShape=box{<-1,-.4,-.6>,<1,.4,.6>}  // Shape of samples

// Demonstration of "ordinary" ferromagnetic
// sample in the top half of the image:
#object {MagnetPair translate <0,2,0>}  // Magnets

#object {SampleShape  // Leftmost sample object
  rotate <100,15,0>   // "Turn and tumble" it
  pigment {           // Apply color gradient to
    gradient x        // indicate presence of
    color_map {       // magnetic poles
      [0 color rgb .75]
      [1 color rgb <.75,.25,.25>]      
      }
    scale 2.3
    translate <-1.15,0,0>
    }
  finish {ambient .4} // To slightly "flatten" shadows 
  translate <-1,2,0>   // Move to position
  }

#object {SampleShape    // Rightmost sample object
  rotate <-120,-30,90>  // "Turn and tumble" it
  pigment {             // Apply color gradient to
    gradient x          // indicate presence of
    color_map {         // magnetic poles
      [0 color rgb .75]
      [1 color rgb <.75,.25,.25>]      
      }
    scale 1.5
    translate <-.75,0,0>
    }
  finish {ambient .4} // To slightly "flatten" shadows 
  translate <1.5,2,0>   // Move to position
  }

// Demonstration of an orthomagnetic sample
// in the bottom half of the image:
#object {MagnetPair translate <0,-2,0>} // Magnets

#object {SampleShape  // Leftmost sample object
  rotate <100,15,0>   // "Turn and tumble" it
  pigment {
    object {  // Arrows to indicate orthomagnetism
      #object {ArrowSet rotate <100,15,0>}
      pigment {     // Apply color gradient
        gradient x  // to indicate presence
        color_map { // of magnetic poles
          [0 color rgb .75]
          [1 color rgb <.75,.25,.25>]      
          }
        scale 2.3
        translate <-1.15,0,0>
        }
      pigment {color rgb 0} // Color of arrows
      }
    }
  finish {ambient .4} // To slightly "flatten" shadows 
  translate <-1,-2,0> // Move to position
  }

#object {SampleShape    // Rightmost sample object  
  pigment {
    object {  // Arrows to indicare orthomagnetism
      #object {ArrowSet}
      pigment {color rgb .5}// No poles, so no color gradient!
      pigment {color rgb 0} // Color of arrows
      }
    }
  finish {ambient .4} // To slightly "flatten" shadows 
  rotate <-120,-30,90>
  translate <1.5,-2,0> // Move to position
  }

background {color rgb 1}  // White background

camera {  // Point of view:
    location <0,2,-8> // Seen from this location
    look_at <0,0,0>   // looking towards this location      
    }

// Illumination:
light_source {<20,10,-15> color rgb 1}
light_source {<-10,20,-10> color rgb 1}