TopWare 18: Liquid/Image.iso/liquid/top1151/frct2pov.txt

Text File | 1994-01-03 | 21KB | 503 lines

               -=> Fractint to POV-Ray v0.5 <=-

                  -=> by David Grossman <=-

                        -=> 1/3/94 <=-


Requires:

        Fractint v16 or later
        POV-Ray 2.0 or later
        Some familiarity with both

Introduction:

     Fractint to POV-Ray ( hereafter referred to as 'FRCT2POV' )
reads a specified parameter set from a Fractint parameter file
and performs the required rotation and scaling in order to
reproduce the identical image in POV-Ray with the 'mandel'
pigment specification. This allows one to map a fractal
Mandelbrot image onto an object in POV-Ray without using an
image_map of a gif. The original Fractint Mandelbrot can be
unevenly scaled, rotated and skewed ( non-perpendicular edges )
and FRCT2POV will still be able to convert it. FRCT2POV will also
attempt to convert the Fractint color map into a POV-Ray
compatible 'color_map'.
     There are a number of advantages to using the 'mandel'
texture instead of an image_mapped Fractint gif. One advantage is
that all detail in the Mandelbrot set is retained over all areas.
An 'image_map' of a Mandelbrot 'gif' obtained from Fractint will
be of inferior quality when mapped onto an object. Negligible
extra memory is needed to do a 'mandel' texture when compared to
the amounts required by a 'image_map', especially large images or
multiple images. Another advantage is the fact that the number of
times a color map is repeated can be modified in POV with the
frequency keyword whereas in Fractint this frequency is fixed.
The 32767 upper limit on the maximum number of iterations in
Fractint is not imposed in POV-Ray. ( This limit would only
affect the extremely 'deep' mandelbrots but in general is not
very important. ) True-color (24 bit) images with anti-aliasing
can also be obtained with POV-Ray. ( I am not sure how Fractint
works in true-color mode. ) Of course there are many
disadvantages to the POV-Ray 'mandel' texture compared with the
Fractint Mandelbrot. One important disadvantage is that POV-Ray
limits the number of entries in the 'color_map' to 20. This
doesn't mean you can only use 20 colors but that you can only
have 20 color 'nodes'. See the POV-Ray documentation on this
subject. Another disadvantage is that POV-Ray doesn't support any
of the 'goodies' that are included in Fractint. From all of the
'basic options' that Fractint supports, only the maximum number
of iterations can be used. None of the 'extended options' are
supported. ( Color cycling is supported in a different manner. )
None of the Mandelbrot 'parameters' are supported either.
Although this may seem very limiting, many of the 'Mandelbrot
set' images that are commonly seen are just basic Mandelbrots
with an interesting color map applied. There are infinite
possibilities for creating beautiful fractal textures. In POV-
Ray, rendering time increases depending on the location in the
Mandelbrot set when using the 'mandel' texture. When using an
'image_map', the set does not have to be calculated as it is
rendered. If you only want to do a planar Mandelbrot image, an
'image_map' may still be the way to go. If you want a complex or
very large object to have a Mandelbrot texture, then a POV-Ray
'mandel' pigment will be the best solution.

Notes on Fractint input files:

     FRCT2POV assumes that the specified parameter is a
Mandelbrot. ( It doesn't check. ) The only information that is
read from the parameter file is the parameter name, 'corners=',
'maxiter=', 'colors='. This means that you can have an
interesting mandelbrot with all of the cool Fractint options such
as biomorph, decomposition, log palette, etc. and still be able
to convert the basic Mandelbrot to POV-Ray. ( The POV-Ray
Mandelbrot will not look exactly the same as the Fractint version
but it will represent the same location in the set. )
     The color map can be specified in the parameter file as a
file name 'colors=@filename.map', it can be encoded, or it can be
specified on the command line.

Notes on color map conversion:

     Fractint to POV-Ray converts Fractint color maps by finding
the largest intervals that can be represented by a smooth color
transition between two fixed colors. These colors are then
assigned as POV-Ray color_map entries. Due to the fact that
Fractint color maps are rounded to the nearest factor of 4, the
conversion process is not perfect. It calculates the maximum
error that occurs when determining the smooth color transition
and if this error is less than a specified value, it saves the
endpoint colors as 'nodes' or color_map entries. This error
starts at the value specified by 'mm=' and is then increased
until the color map can be converted with less than or equal to
twenty entries. ( this limit is imposed by POV-Ray ) If the
maximum error is increased past a limiting value of 20 and the
color map entries exceed 20 ( no relation to the previous '20' )
the color map is not written. If the error becomes too big then
the color_map will bear little resemblance to its original
Fractint map. The default starting value for the starting
'maximum error' value is 4. Color maps that are converted at this
value are very accurate.

Notes on output files:

     FRCT2POV output files consist of a 'header' which states
which file, parameter, and color map was converted as well as the
'#declare'd names and '.inc' file name. The time and date that
the file was converted is also shown. ( File 'header' information
can be turned off if desired. ) By default, the POV 'color_map'
is embedded in the '#declare'd texture. ( The color_map can be
'#declared' and then used in the '#declare'd texture if desired.
) The '#declare'd names can be specified or defaulted to the name
of the converted parameter and color map.
     This version of FRCT2POV '#declare's the Mandelbrot as a
'pigment' rather than a 'texture'. In the new POV ( 2.0 or later
) 'pigment' implies 'texture'. In later versions of FRCT2POV, a
'texture' may be '#declare'd with embedded 'normal', 'finish' and
additional transformation specifications.
     The specified Mandelbrot set is first translated to the
origin. Then is rotated and scaled. ( If required )
     Some rotated and skewed Mandelbrot sets require two sets of
rotations and scaling. In this case, the first rotation orients
the set to the optimum position to 'skew' the image with the
subsequent scaling. The image is then rotated and then scaled to
its final position. ( The fact that unskewed, rotated Mandelbrots
are still subjected to the unskewing rotation and scaling is due
to numerical inaccuracies when testing for perpendicular axes.
This problem will be fixed in the next version. )
     By default, the Mandelbrot image is scaled to fit the area
bounded by the lines x= +/-1 and y= +/-0.75 . This allows you to
scale the texture accurately. ( Note that this window aspect
ratio is the same as the most common video modes used in Fractint
and POV-Ray )

Installation:

     Please see the file INSTALL.TXT for installation
instructions.

Fractint to POV-Ray file list:

     Please see the file FILELIST.TXT for information on the
Fractint to POV-Ray package files.

Operation:

     FRCT2POV is operated from the command line. Like POV-Ray,
parameters are read first from an initialization file and then
from the command line. An additional initialization file may be
specified on the command line and will be read after the default
ini file and before the command line parameters. ( only one
additional '.ini' file is supported in this version. )

Sample Scenes:

     There are a number of sample scenes included under the names
'f2pscn?.pov'. The first sample scene 'f2pscn0.pov' is just a 2-D
representation of the specified Mandelbrot that is viewed in such
a way that it recreates the identical image from Fractint. See
the file 'filelist.txt' file for more information on the other
scenes.
     These scenes '#include' the file 'frct2pov.inc' and use the
name frct2pov for the texture name. When you convert a fractal
with Fractint to POV-Ray, the program outputs the 'frct2pov.inc'
file. ( unless you tell it not to ) This file '#include's the
output file you just converted and re'#declare's the texture name
of that texture. All you have to do to trace a test scene is to
convert a parameter and then trace the scene. No editing is
required. You can always edit the 'frct2pov.inc' file to specify
a previously created texture.

Procedure:

     The first step in creating a Mandelbrot texture in POV-Ray
is to run Fractint, create a Mandelbrot image with the desired
color map. ( see the Fractint documentation on these subjects )
Then save it to a parameter file by using the 'B' key. Specify a
parameter file to hold your Mandelbrots and use the same
parameter file for all of your FRCT2POV conversions. ( You can
have multiple images in a parameter file. ) You can specify your
parameter file in the FRCT2POV '.ini' files so you do not have to
enter it in at the command line. In the 'save colors?' section
you can enter 'y' to save your current color map, or specify a
file name. These are the only necessary parameters. Note that any
color map specified on the command line will override the color
map specified in the parameter.
      The next step is to run 'FRCT2POV.EXE' with the correct
command line parameters. ( See the following discussion on
command line parameters. )
    The final step is to '#include' the outputted file into
whatever scene file you want to use it in and specify the
'#declare'd texture name in your object's texture statement. You
can add 'normal' and 'finish' statements to the texture
statements. You can also trace any of the sample scenes without
any editing.

IMPORTANT NOTE!

    FRCT2POV and POV-Ray do not check to see if they are
overwriting an output file. If you want to save a previously
created scene or texture you must specify different output file
names on the FRCT2POV and POV-Ray command lines or rename the
previously created output files.

Quick reference:

     See the file 'frct2pov.ini' for a quick reference to all
FRCT2POV parameters.

Parameter Syntax:

    All parameters must be specified in the form 'xx=parameter'.
On the command line they are separated by spaces. e.g.

frct2pov pf=fractals.par pn=mymandel ce=y ff=3 do=n

    In the '.INI' files, each parameter must begin on a new line
with no leading spaces. Everything after the first space
encountered is ignored.

IMPORTANT NOTE!

     FRCT2POV only looks for parameters it understands and
ignores everything else. If you misspell a parameter
specification prefix ( 'ff=' ), FRCT2POV will not notify you of
the error but will ignore it. ( Future versions will notify you
of these errors. ) This is why you can have all sorts of extra
baggage in the '.ini' file without causing an error.

    Flag parameters ( on/off only ) are specified with a 'y' or
a '1' for on and a 'n' or a '0' for off 'yes' and 'no' are also
acceptable ( FRCT2POV only looks at the first letter ).

Parameters: ( shown with defaults )

//      input parameters

in=none     INitialization file name

   This parameter is only used from the command line. It
specifies a second initialization file that is to be read after
the default 'frct2pov.ini' file. This can be used to specify
parameters for a frct2pov parameter set. ( Note that since this
file is read after the 'frct2pov.ini' file, only parameters that
need to be changed should be included in this file. )

//      input/output paths

fp=c:\fractint    Fractint Path

   specifies the path to the Fractint .par and .map files.

pp=c:\povray     Pov-ray Path

   specifies the path to the location of .inc file output.

//      Fractint input parameters

pf=f2p.par     Parameter File name   ( filename.par )

   specifies the name of the Fractint parameter file.

pn=f2p01    Parameter Name     ( alphanumeric with no spaces )

   specifies the name of the parameter in the specified '.par'
file that is to be converted.

cf=none     Color map File name  ( filename.map )

   specifies the name of the Fractint color map ( '.map' ) file
that is to be converted. If this parameter is 'none' or is blank,
the color map file name is as specified in the parameter text. If
no color map is specified in the parameter text and is not
specified on the command line then no color map is output.

//      POV-Ray output parameters

ti=none     Texture Include file name  ( filename.inc / .??? )

   specifies the name of the '.inc' texture file that is to be
output. If this parameter is 'none' or is blank then the texture
include filename is taken from the first 8 characters of the
parameter name. Be careful to take this into consideration when
creating output files! The parameter names 'mymandel1' and
'mymandel2' will output the same texture file 'mymandel.inc'.

tn=none     Texture Name    ( alphanumeric with no spaces )

   specifies the name of the '#declare'd texture. If this
parameter is 'none' or is not specified it defaults to the name
of the converted parameter. Since Fractint allows parameters to
begin with numbers and POV-Ray doesn't, names that begin with
numbers are prefixed with 't_'.

cn=none     Color map Name    ( alphanumeric with no spaces )

   specifies the name of the '#declare'd color map. If this
parameter 'none' or is not specified it defaults to the name of
the converted color map. Since Fractint allows parameters to
begin with numbers and POV-Ray doesn't, names that begin with
numbers are prefixed with 'c_'. If the color map name is the same
as the parameter name then it is prefixed with 'c_'.

//      output options

wt=yes     Write Test include file   ( yes/no )

   specifies whether the 'frct2pov.inc' file is written.

ih=yes     Include Header  ( yes/no )

   specifies whether the header conversion information is written
to the texture include file.

ce=yes     Color map Embed   ( yes/no )

   specifies whether the color map is written directly into the
Mandelbrot 'pigment' instead of declared. ( prevents errors if
multiple color maps are declared in the same '.pov' or '.inc'
file.

ta=no     Texture include Append   ( yes/no )

   specifies whether the texture '.inc' file is appended to an
existing file. ( allows you to make libraries of mandelbrot
textures similar to 'textures.inc' and 'stones.inc'. ( Remember
that all '#declare'd names must be unique. )

do=yes     Display Output   ( yes/no )

   specifies whether the outputted file is displayed after it is
written. ( implemented as a dos 'type filename.inc | more'
command )

ab=yes     display About information     ( yes/no )

   You can disable the output of the Fractint to POV-Ray
'about' information. This information is only outputted to the
screen and not to any files.

mm=4     Maximum Error start value  ( 2, 19 )

   specifies the minimum starting value for the tolerance in
color map conversion. ( see the 'Notes on color map conversion' )

//    texture options

mi=0    Maximum number of Iterations ( integer > 0 | 0 for none )

   specifies the maximum number of iterations that are performed
in creating the Mandelbrot texture. If this parameter is '0' or
unspecified its value is taken from the parameter text. If it is
not specified in the parameter text it is given a default value
of 32640.( see the Fractint documentation for more information on
this topic )

ff=1     Frequency Factor      ( nonzero )

   specifies a multiplication factor that is written to the POV-
Ray 'frequency' specification. This adjusts the number of times
the color map is repeated. The default frequency that is output
is calculated to duplicate the color distribution in the original
Fractint image. In POV-Ray, this distribution can be changed
whereas in Fractint it cannot. ( except in different ways such as
with a logarithmic palette which is not possible in POV-Ray )(
see the POV-Ray documentation for more information on this topic
)

ph=0     PHase      (  >=0 & <=1  )

   specifies the starting point of the POV-Ray color map.
Effectively duplicating the ability to 'cycle' the POV-Ray color
map as can be done in Fractint ( see the Fractint documentation
for the topic of color cycling and the POV-Ray documentation for
the topic of 'phase' )

xw=2      X-Window size     (  real >0 )
yw=1.5    Y-Window size     (  real >0 )

   specifies the horizontal and vertical size of the output
texture in POV-Ray space. The window specified by the X and Y-
Window sizes determine the region in which the specified
Mandelbrot resides. The ratio of X-Window to Y-Window should be
the same as the aspect ratio of the video mode in which the
Mandelbrot was created in Fractint for the image to be converted
accurately. ( for most video modes this ratio is 4/3 ) ( Note
that the Mandelbrot texture extends infinitely beyond this window
size. )


//      manual parameter input

Manual parameter input allows you to create a Mandelbrot texture
include file without a Fractint parameter file. However, you must
specify a Color map File name ( cf= ) in order to output a color
map. In order to use manual parameter input, either WIdth or
Magnification must be specified.

xc= X-Center     ( real )
yc= Y-Center     ( real )

   specifies the where the center of the Mandelbrot texture is
located in Mandelbrot space. Many books provide center/width
information about their Mandelbrot images. ( only used with WIdth
and MaGnification )( note that only values within the proximity
of the actual Mandelbrot set produce interesting results )

wi= WIdth     ( real )

   specifies the width of the desired Mandelbrot in Mandelbrot
space.

mg= MaGnification   ( real )

   specifies the magnification of the desired Mandelbrot in
Mandelbrot space. ( this specification overrides WIdth if both
are given )


Coming soon:

( may be included in later versions depending on user response )

provisions for POV-Ray 'filter' specs
less restrictive file name specs
multiple .ini files may be specified
ability to pass on parameter comments to the '.inc' file header

or= ORientation      image aligned with specified axes.

xtl= X-Top-Left      for manual input ( not really necessary )
ytl= Y-Top-Left
xbr= X-Bottom-Right
ybr= Y-Bottom-Right
xbl= X-Bottom-Left
ybl= Y-Bottom-Left

ca= Color map include Append
mo= Mandelbrot Only
co= Color map Only
ci= Color map Include filename

embedable texture and transformation specs:

finish {}
normal {}
scale <>
rotate <>
translate <>
#include "colormap.inc"
//  user specifiable comment lines in texture

Other texture types may be included in the package.

Starfield textures ( with options )
Cloud textures  ( with options )


Fractint to POV-Ray history:

v0.5      First and possibly only version.


Legal information:

     Please see the file 'f2plegal.txt' for this information.


Thanks to:

The creators of POV-Ray and Fractint for their fantastic
programs.


Distribution information:

     Although I am distributing this program as 'free-ware', I am
asking for a small donation as I have spent a lot of extra time
creating sample parameters, scene files, and documentation. I
have also incorporated many features that were originally planned
for later versions. If you find this program useful I would
appreciate it if you would send me five or ten dollars ( or more
if you want ). Instead of or in addition to money, I would also
like to see your raytraces. You could send them to me in the mail
or upload them to the raytracing BBS 'You Can Call Me Ray' or to
America Online.

    You can reach me on America Online as DavidG6784, on Internet
as [e-mail] or on 'You Can Call Me Ray' as Dave
Grossman. See the POV-Ray documentation for information on the
YCCMR BBS. All questions will be answered promptly and any
comments would be appreciated.

    If you decide to send a donation and/or copies of your work
( 3.5" 1.44M media is preferred ), my address is:

     David Grossman
     2516 Prairie Ave #1C
     Evanston, Il. 60201-2285