Trees in PoV and self-generating include files

Some time ago I made an include-file for povray that produces trees. The idea was born in a discusion whether it is possible to do recursion in pov or not. It's not possible, not directly... I found a trick to let povray produce its own include files and to produce nested while statements in this self-generated include files, which is equal to recursion.

You may have a look at these three trees. They are made with my include file (if you use xv, you should increase the gamma value, the pics are rendered with for very bright displays...)

437481 bytes 368896 bytes 436673 bytes

The tree sources:

• tree 1
• tree 2
• tree 3
• the leafes (they are not good, I'm planning better ones...)

Here's the include file which makes those trees: selftree.inc.

Ah, sorry. This is a newer version of the include file (see below), if you want to render these trees by yourself (they take VERY LONG time!), take this older version: selftree.old.inc

Sorry, documentation is in german only. If you want to know, how to use it, you can read this documentation (sorry, it's written in german, too...): Postscript-Version LaTeX-File

The docs are not ready yet...

A note: In the docs most of the parameters are simple numbers. I think, that is not flexible enough. So I changed the include file. Now you can use komplex functions for nearly all parameters. If you look at the include file, all values that are enclosed in parentheses should work with functions, all other should be simple numbers or names. Try some values and functions to see, which are good.

How does it work?

#declare depth = 3
#declare second = depth

#while (depth>0)

   #debug "#while bla bla bla\n"
   #debug "some code\n"
   #declare depth = depth-1

#end

#while (second>0)

   #debug "#end\n"
   #declare second = second-1

#end

#while bla bla bla
some code
#while bla bla bla
some code
#while bla bla bla
some code
#end
#end
#end

How do I use it??

• 1: Declare some of the variables described below
• 2: include selftree.inc
• 3: include the file produced by the output of selftree.inc
• 4: say object { OBJECTNAME }

Here are all the variables and their defaultvalues, you can set:

• OBJECTNAME = "TREE"
  name of the object, you can produce more than one tree in your includefile by including selftree.inc multiple times. Then you should declare OBJECTNAME with different values.
• USESTDTRUNK = "YES"
  use the standard trunk? (Which is only a simple cone)
• TRUNKLEN = "5"
  How long is the trunk? (FLOAT, >0)
• TRUNKBASER = "1"
  The base radius of the trunk (FLOAT, >0)
• TRUNKCAPR = "0.5"
  The cap radius of the trunk (FLOAT, >0)
• DEPTH = 4
  The depth of the recursion to produce (INT, >0)
• BLEN = "5"
  Length of the branches in the first recursion step (FLOAT, >0)
• LDIFF = "0"
  divergence to blen (is randomly added to BLEN) (FLOAT, LDIFF> -BLEN)
• RADIUS = "0.5"
  Radius of the branches in the first recursion step (FLOAT, >0)
• RADSCALE = "0.5"
  how to scale the values for the branches between the recursion steps (FLOAT, >0)
• RDIFF = "0"
  divergence for the branch radius (subtraceted) (FLOAT, |RDIFF| RECSCALE = "0.5"
  how to scale all other values (FLOAT, >0)
• SLOPEANGLE = "45"
  slope angle for the branches (FLOAT)
• SANGLEDIFF = "0"
  divergnecy for the slope angle (added to SLOPEANGLE) (FLOAT)
• ANGLESCALE = "1"
  how to scale the slope angle (FLOAT)
• NRBRANCHES = "4"
  how many branches (this is not how many branches for the whole tree, but for every branch. so if you say NRBRANCHES = 4 , evere produced branch has 4 child branches up to the DEPTHs recursion (INT, >0)
• NRBDIFF = "0"
  divergence for NRBRANCHES (added to NRBRANCHES) (FLOAT)
• NRBSCALEADD = "0"
  how to scale NRBRANCHES (added to NRBRANCHES)(FLOAT)
• NRBSCALEMUL = "1"
  how to scale NRBRANCHES (multiplied with NRBRANCHES)(FLOAT)
• BRANCHTOP = "1"
  where to put the child branches (1 = allways at the top of their parents, 0 = somewhere at their parents) (FLOAT, 0<=x<=1)
• LEAFINC = "NO"
  have a leaf-include file? (STRING, YES|NO)
• NRLEAFINCS = 0
  How many different leafs are in the include file? the names of the leafobjects shoul be LEAFSHAPE_00, LEAFSHAPE_01... (INT, >=0)
• NRLEAFS = "0"
  how many leafs per branch (INT, >=0)
• NRLDIFF = "0"
  diverngence for NRLEAFS (wird zu NRLEAFS addiert)(INT, NRLDIFF> -NRLEAFS)
• ROTRANGE = "360"
  how to rotate the branches around their parents. normaly the range would go up to 360 degrees, but if you minimize this value, you can produce some kind of wind to the tree (works not very good) (FLOAT, 0<=x<=360)
• RANDINIT_ROT = "0.1234"
  Init-value for random stream for ROTRANGE (FLOAT)
• RANDINIT_LDIFF = "0.1234"
  Init-value for random stream for LDIFF (FLOAT)
• RANDINIT_RDIFF = "0.1234"
  Init-value for random stream for RDIFF (FLOAT)
• RANDINIT_SDIFF = "0.1234"
  Init-value for random stream for SANGLEDIFF (FLOAT)
• RANDINIT_NRBDIFF = "0.1234"
  Init-value for random stream for NRBDIFF (FLOAT)
• RANDINIT_NRLDIFF = "0.1234"
  Init-value for random stream for NRLDIFF (FLOAT)
• RANDINIT_LEAFSELECT = "0.1234"
  Init-value for random stream for selecting the different leafs (FLOAT)
• RANDINIT_LEAFTRANS = "0.1234"
  Init-value for random stream for positioning the leafs (FLOAT)
• RANDINIT_LEAFROT = "0.1234"
  Init-value for random stream for leaf rotation (FLOAT)
• RANDINIT_BT = "0.1234"
  Init-value for random stream for BRANCHTOP (FLOAT)
• #default { pigment { color rgb <0.35, 0.16, 0.14> } }
  define a default texture for the branches... You can also define different textures for the braches in the different recursion steps. For the texture for the trunk use #declare MOD_TR = texture { bla bla bla } for the branches in the first recursion step use MOD_0 = texture { bla bla bla } and so on. If the textures are not defined, default texture is used.

There some more tools I made for and with pov. I hope, they will appear here anytime (too lazy...).

Have fun,
Stephan Kuhagen