adammaj1 / pfract

FRACTALS IN POLAR COORDINATES, It is fork of original code by Mika Seppä

Fractals in the polar coordinate.

It is fork of the original code by Mika Seppä

Description

Original image (FractExample5.png)

Modified images

• crop = Cutout = cut ( defining a rectangle in pixels and choose only this rectanle, removing the other parts of an image). Why : because most of image is not interesting exterior of Mandelrots/Julia sets

Here is standard c plane ( flat image = rectangle from Cartesian plane) with marked part of the plane which is showed in the polar image

Mandelbrot set ( polar images)

Image ( example5)

xSize=8000
ySize=800
./pfract -x 0.160211 -y -0.684246 -size $xSize $ySize -iterations 256 -rad -10 example5.raw
./colorize example5.raw example5.ppm -spawn -400 -scale 1.6 -fadedepth 25

New image ( example 7): only one minibrot from above image, more distorted

xSize=8000
ySize=800
./pfract -x 0.360211 -y -0.684246 -size $xSize $ySize -iterations 256 -rad -10 example7.raw
./colorize example7.raw example7.ppm -spawn -400 -scale 1.6 -fadedepth 25

New image ( example 8): more cetered zoom, different diatorsion of decorations

xSize=8000
ySize=800
./pfract -x 0.360211 -y -0.57 -size $xSize $ySize -iterations 256 -rad -10 example8.raw
./colorize example8.raw example8.ppm -spawn -400 -scale 1.6 -fadedepth 25
convert example8.ppm example8.png
# crop the image with shotwell

Here is an example how number of iterations ( -iterations) can change the image: for the first one is 256 and for the second one is 20000 ( see also commons and wikibooks):

./pfract -x -1.7864402555636389  -y 0 -size $xSize $ySize -iterations 256 -rad -20 e9.raw
./colorize e9.raw e9.ppm -spawn -400 -scale 1.6 -fadedepth 25
convert e9.ppm e9.png
# crop the image with shotwell

./pfract -x -1.786440255563638  -y 0 -size 2400 800 -iterations 20000 -rad -20 1.786440255563638.raw
./colorize 1.786440255563638.raw 1.786440255563638.ppm -spawn -400 -scale 1.6 -fadedepth 25
convert 1.786440255563638.ppm 1.786440255563638.png

Julia sets ( polar images)

Exponential map and polar coordinate

• wikibooks

Compilation and execution of the program

sfp

Single file program ( sfp) - only 1 c file with 250 lines:

  gcc p.c -lm -Wall -Wextra 
  ./a.out

bash version

My version of the program can be compiled and run with simple

make

or

./r.sh

Detailes are in

• Bash scripts
  • d.sh
  • r.sh
• Makefile

Original code execution

pfract -julia -cx -1.115313 -cy -0.304872 -x -0.147394 -y -0.234163 -size 1600 160 -iterations 164 -rad -8 example1.raw
colorize example1.raw example1.ppm -fadedepth 20 -scale 1.4

Files

Source code

• original , non modified files are in src/original directory
• my ( modified) files are in src directory
• bash version - slightly modified
• single c file the program ( sfp) - change from multi (2 c files and one bash file) files program to one file program
• Images = png files are in png directory
• Documantation is in the doc directory

Raw file specification

• binary file
• contains data

 0- 7 : Magic number "ITERFILE"
 8- 9 : Image width
10-11 : Image height
12-13 : Number of bytes per iteration value (NBYTES)

IF NBYTES=2:
14-15 : Maximum iterations
16-   : Data (2 bytes per iteration value)

IF NBYTES=4:
14-17 : Maximum iterations
18-   : Data (4 bytes per iteration value)

see also

• Can you find the location of this fractal ?

To do

• show on normal plane what part of that plane is transformed
• make one file c program (sfp = Single File Program). I think that because of short compiling and running time of original code there is noneed for dividing cration of the image into steps)
• modify the program to show more image to the left
• make program specification

Git

create a new repository on the command line

echo "# PFRACT" >> README.md
git init
git add README.md
git commit -m "first commit"
git branch -M main
git remote add origin [email protected]:adammaj1/PFRACT.git
git push -u origin main

Repo

Change:

• in general settings
  • add Social Preview Image ( Images should be at least 640×320px (1280×640px for best display))
• in repository details ( near About) add
  • description
  • website
  • Topics (separate with spaces)

Local repository

/Dokumenty/algorithm/pfract

Subdirectory

mkdir png
git add *.png
git mv  *.png ./png
git commit -m "move"
git push -u origin main

then link the images:

![](./png/n.png "description") 

to overwrite

git mv -f 

git mv ./src/*.c ./src/modified/bash/
git mv ./src/*.sh ./src/modified/bash/
gitt mv ./src/Makefile ./src/modified/bash/

Github

• GitHub Flavored Markdown Spec
• md cheat sheet
• CommonMark Spec
• Markdown parser