Reusing Shapes

Make a Spear

#include "include/colors.inc"

camera {
  location <0, -8, 0>
  look_at <0, 0, 0>
}

cone {
  <-4, 0, 0>, 0  
  <-1.5, 0, 0>, 0.8  
  pigment { Silver }
}

cylinder {
  <-3, 0, 0>,    
  <5, 0, 0>,    
  0.3              
  pigment { BakersChoc }
}

light_source { <-2,-9,-5> colour White}

Declare Shape

Syntax: #declare shapeName = union { //shape definition here } An example in use:

#declare spear = union {        
	            
                cone {
                    <-4, 0, 0>, 0  
                    <-1.5, 0, 0>, 0.8  
                    pigment { Silver }
                }

                cylinder {
                    <-3, 0, 0>,    
                    <5, 0, 0>,    
                    0.3
                    pigment { BakersChoc }
                }
}

Using Shape

This goes underneath the declaration:

//add one spear:
object { spear } 

//add another spear, move it backwards:
object { spear translate <0, 0, -1> } 

//loops (add 10 spears):
#declare numOfSpears = -5;
#while (numOfSpears < 5)
  object { spear translate <0, 0, numOfSpears> }
  #declare numOfSpears = numOfSpears + 1;
#end

Putting it All Together

#include "include/colors.inc"

camera {
  location <0, -8, 0>
  look_at <0, 0, 0>
}

#declare spear = union {        
	            
                cone {
                    <-4, 0, 0>, 0  
                    <-1.5, 0, 0>, 0.8  
                    pigment { Silver }
                }

                cylinder {
                    <-3, 0, 0>,    
                    <5, 0, 0>,    
                    0.3
                    pigment { BakersChoc }
                }
}

light_source { <-2,-9,-5> colour White}

//add one spear:
object { spear } 

//add another spear, move it backwards:
object { spear translate <0, 0, -1> }

Challenge

turn one of your challenges into a reusable shape, and display it multiple times