point pCenter(0.0 0.0 0.0)
endpoint

point pTop(0.0 1.0 0.0)
endpoint

point pFront(0.0 -0.3338068592 0.9426414911)
endpoint

point pRight(0.8163514779 -0.3338068592 -0.4713207455)
endpoint

point pLeft (-0.8163514779 -0.3338068592 -0.4713207455)
endpoint

face fBottom(pFront pLeft pRight)
endface

face fBack(pTop pRight pLeft)
endface

face fLeft(pTop pLeft pFront)
endface

face fRight(pTop pFront pRight)
endface

object BasicTetra (fBottom fBack fLeft fRight)
endobject

group Spike 
 instance BasicTetra
  scale ({Tail} {Tip} {Tail})
  rotate (0.0 1.0 0.0) ({RotateSpike})
  translate (0.0 {MoveSpike} 0.0)
  rotate (1.0 0.0 0.0) (109.5)
 endinstance
endgroup

group Tetra
 instance BasicTetra
 endinstance

 instance Spike
 endinstance

 instance Spike
  rotate (0.0 1.0 0.0) (120)
 endinstance

 instance Spike
  rotate (0.0 1.0 0.0) (240)
 endinstance
endgroup

# 2c) Finally we need to add the triangles to the World.
group World
 instance Tetra
 scale( {ScaleTetra } {ScaleTetra } {ScaleTetra })
 surface sGreen
 endinstance
endgroup
############################################################################
# 3) Add Color
#
#    In the Triangle group we specified the surface color of each instance.
#    Now we need to define these surfaces.

surface sBlue
  color (0.0 0.0 1.0)
endsurface

surface sGreen
  color (0.0 1.0 0.0)
endsurface

surface sRed
  color (1.0 0.0 0.0)
endsurface

surface sWhite
  color (1.0 1.0 1.0)
endsurface

surface sCyan
  color (0.0 1.0 1.0)
endsurface

surface sPurple
  color (1.0 0.0 1.0)
endsurface

surface s4
  color (0.5 0.5 0.0)
endsurface

surface s5
  color (0.5 1.0 0.0)
endsurface

surface s6
  color (1.0 0.5 0.0)
endsurface

surface sYellow
  color (1.0 1.0 0.0)
endsurface

############################################################################
# 4) Create Sliders with Tcl/Tk
#
#  The following Tcl/Tk code shows how to create the sliders and variables
#  that we referenced above.


#  Make a Tcl initialization block

tclinit {
  set winName .slfWINDOW

  ### include some tcl libraries
  source SLIDEUI.tcl
  source MATH.tcl
  ### This defines a procedure called CreateSliders
  proc CreateSliders { parent name } {
    ### Don't worry about this stuff ...
    set subname "slf_[subst $name]"
    if { $parent == {} } {
	set root .$subname
    } elseif { $parent == "." } {
	set root .$subname
    } else {
	set root $parent.$subname
    }

    toplevel $root


    ### This is where the sliders are actually created ! ! !

    ### variable name       variable name    slider text
    ###  |                             |     |
    ###  V                             V     V       
   set size [CreateScale $name $root size "Size"   1  0.1 2.0 0.1 1 horizontal]
   set tip [CreateScale $name $root tip "Tip"     0.3 0.01 2.0 0.01 1 horizontal] 
   set tail [CreateScale $name $root tail "Tail"  0.3 0.01 2.0 0.01 1 horizontal] 
   set start [CreateScale $name $root start "Spike Position"  0.7 0.01 1.0 0.01 1 horizontal] 
   set rot [CreateScale $name $root rot "Spike Rotation"  60 0 120 1 1 horizontal]
    ###                                            ^  ^   ^  ^
    ###                                            |  |   |  |
    ###                     initial slider value---'  |   |  |
    ###                     minimum slider value------'   |  |
    ###                     maximum slider value----------'  `- slider step value



    ### This line is important too.  This tells the window to display the sliders.

    pack $size $tip $tail $start $rot -side top -fill x
  }

  ### This calls the procedure that creates the sliders
  CreateSliders $winName stat

  proc ScaleTetra {} {
   global stat_size
   return [expr $stat_size*0.25]
 }

  proc Tip {} {
   global stat_tip
   return $stat_tip
 }
 
 proc Tail {} {
   global stat_tail
   return $stat_tail
 }

 proc MoveSpike {} {
   global stat_start
   return $stat_start
 }

 proc RotateSpike {} {
   global stat_rot
   return $stat_rot
 }
}
########################################################################################
# The code below this line specifies the camera, lighting, and rendering.
# Don't worry too much about this for now.
#################### 
# CAMERA
#################### 

camera cam
  projection SLF_PERSPECTIVE
  frustum ( -0.5 -0.5 -2 ) ( 0.5 0.5 -0.2 )
endcamera

group gCamera
  instance cam
    id instCam
    translate ( 0.0 0.0 1.0 )
  endinstance
endgroup
#################### 
# LIGHTS
#################### 

light lAmbient
  type SLF_AMBIENT
  color ( 0.2 0.2 0.2 )
endlight

light lTop
  type SLF_DIRECTIONAL
  color ( 1.0 1.0 1.0 )
endlight

group gLight
  instance lTop
    id iTop
    lookat
      eye ( 0 0 0 )
     target ( -1 -1 -1 )
      up ( 0 1 0 )
    endlookat
    translate ( 1 1 1 )
  endinstance
endgroup

####################
# RENDER
####################
window WINDOW
#  background ( 0.25 0.60 1.0 )
endwindow

viewport VIEWPORT WINDOW
endviewport

render VIEWPORT gCamera.instCam.cam World
  light lAmbient
  light gLight.iTop.lTop
endrender