Instructions for modifying the woods texture files.
By Laura Berry

This file contains the instructions for modifying the wood include 
files (woodmaps.inc and woods.inc) so that the commands #include 
"woods.inc" and #include "woodmaps.inc" will allow you to use the 
modified wood grain called up by texture {T_Wood1tt}

Insert the following four lines into woods.inc:

// Natural oak (light) transparent 2   
#declare T_Wood1tt =                                                                      //Laura's
    texture { pigment { P_WoodGrain1A  color_map { M_Wood1At }}}
    texture { pigment { P_WoodGrain1B  color_map { M_Wood1Bt }}}    

I recommend placing it below the other Natural oak woodgrains, located
a little more than halfway down the file.

Insert both of the following into woodmaps.inc.  I recommend placing 
the first near the beginning of the file under #declare M_Wood1A and
placing a second a little lower under #declare M_Wood1B:

#declare M_Wood1At =
color_map { 
    [0.0, 0.1 color rgbt <0.88, 0.60, 0.40, .6>
              color rgbt <0.88, 0.60, 0.40, .6>] //Laura
    [0.1, 0.9 color rgbt <0.88, 0.60, 0.40, .6>
              color rgbt <0.60, 0.30, 0.20, .6>]
    [0.9, 1.0 color rgbt <0.60, 0.30, 0.20, .6>
              color rgbt <0.60, 0.30, 0.20, .6>]
}

#declare M_Wood1Bt = 
color_map { 
    [0.0, 0.1 color rgbt <0.55, 0.32, 0.20, 0.650> 
              color rgbt <0.55, 0.32, 0.20, 0.750>]
    [0.1, 0.2 color rgbt <0.55, 0.35, 0.20, 0.700>
              color rgbt <0.88, 0.60, 0.40, 0.975>]
    [0.2, 0.3 color rgbt <0.88, 0.60, 0.40, 0.975>                                //Laura
              color rgbt <0.60, 0.30, 0.20, 1.000>]
    [0.3, 0.4 color rgbt <0.60, 0.30, 0.20, 0.650> 
              color rgbt <0.60, 0.30, 0.20, 0.750>]
    [0.4, 0.9 color rgbt <0.60, 0.30, 0.20, 0.700>
              color rgbt <0.88, 0.60, 0.40, 0.975>]
    [0.9, 1.0 color rgbt <0.88, 0.60, 0.40, 0.975>
              color rgbt <0.55, 0.32, 0.20, 1.000>]
}