<pet### [at] somewhereinuk> wrote 
> Here's my povray source

Try the below code.  
Is this what you want?

R. Suzuki
-----------------------------------------------------
#version 3.5;
#include "colors.inc"
#include "functions.inc"
#declare CamLoc = <-8, 0,0>;
camera { location CamLoc look_at <0,0,0> angle 45 }
light_source {CamLoc color White*0.35}
light_source {<-50, 150,-75> color White}
#declare IsoFinish = finish { ambient 0.35 diffuse 1 specular 1
                              roughness 0.02 brilliance 2 }
#declare vel = <35,25,45>;
#declare velx = vel.x;
#declare vely = vel.y;
#declare velz = vel.z;
#declare f_vcrossmag = function(v1x,v1y,v1z,v2x,v2y,v2z) {
        sqrt( (v1y*v2z - v1z*v2y)^2 + (v1z*v2x - v1x*v2z)^2
              + (v1x*v2y - v1y*v2x)^2 )
}
#declare f_bfield = function(x,y,z,vx,vy,vz) {
        f_vcrossmag(vx,vy,vz,x,y,z) / pow(f_r(x,y,z),3)
}
isosurface { function {
               max(-1, 
                   -(f_bfield(x,y,z,velx,vely,velz) - 6)
               )
                  }
        max_gradient 20 threshold 0 contained_by {box{-3.2, 3.2}}  
        accuracy 0.01      
        evaluate 10,1.1,0.99
        texture { pigment {color Red} finish {IsoFinish} }
        scale 1/vlength(1)
}

Post a reply to this message