In this section I want to demonstrate some elementary applications of the while loop in POV-Ray.
In this applications the while loop is used for the regular placing of objects. The following samples want to demonstrate single and nested loop.

Note: All POV-Ray scene files of the following samples are downloadable (extension: .pov, alternativly also as .txt text files!). Most of the sample POV-Ray scene files use the include file "axis_xyz.inc" for the coordinate system. This file can be downloaded here: as a ".inc" file or as a ".txt" file (Save it renaming the extension to ".inc"!).

First we consider a single loop which places little spheres along the x axis from x = -5 to x = +5:

//------------------------------------
#declare Ball =
 sphere{<0,0,0>,0.5
	texture{pigment{color Red}
                finish {ambient 0.15
                        diffuse 0.85
                        phong 1}
               }
        }
#declare NrX = -5;     // start
#declare EndNrX = 5; // end
#while (NrX < EndNrX+1)
 object{Ball translate <NrX,0,0>}

 #declare NrX = NrX + 1;  //next Nr

#end // ------------- end of loop ----

Scene file for POV-Ray: .pov or: .txt

If we nest an existing loop in another loop which steps through the values from z = 0 to z = +5, we get a rectangular field covered by identical objects:

//------------------------------------
#declare Boxy =
 box {<0,0,0>,< 1,1,1> scale 0.5
 	texture{pigment{color White}
                finish {ambient 0.1
                        diffuse 0.9}}}
#declare DistanceX = 1.00;
#declare DistanceZ = 1.00;
#declare NrX = 0;      // startX
#declare EndNrX = 7;   // endX
#while (NrX < EndNrX) // <-- loop X
 #declare NrZ = 0;     // start
 #declare EndNrZ = 7;  // end
 #while (NrZ < EndNrZ) // <- loop Z
 object{Boxy
        translate<NrX*DistanceX, 0,
                  NrZ*DistanceZ>}
  #declare NrZ = NrZ + 1;  // next NrZ
 #end // --------------- end of loop Z
 #declare NrX = NrX + 1;// next NrX
#end // ------------- end of loop X --

Scene file for POV-Ray: .pov or: .txt

It is posibble to nest a nested loop in an additional loop, which steps through the values from y = 0 to y = +5. With this we get a box formed by identically formed objects:

//------------------------------------
#declare DX = 1.00;
#declare DY = 1.00;
#declare DZ = 1.00;
#declare NrX = 0;      // startX
#declare EndNrX = 5;   // endX
#while (NrX < EndNrX)
 #declare NrY = 0;     // startY
 #declare EndNrY = 5;  // endY
 #while (NrY < EndNrY)
  #declare NrZ = 0;    // startZ
  #declare EndNrZ = 5; // endZ
  #while (NrZ < EndNrZ)
  object{Boxy
         translate
            <NrX*DX,NrY*DY,NrZ*DZ>
        }
  #declare NrZ = NrZ+1;// next NrZ
  #end // ---------- end of loop Z
 #declare NrY = NrY+1;// next NrY
 #end // ---------- end of loop Y
 #declare NrX = NrX+1;// next NrX
#end // ----------- end of loop X ----

Scene file for POV-Ray: .pov or: .txt

With this sample our possibilities regarding to pure linear transformations with loops seam to be exhausted in our three dimensional world.