README more readable and usefull
LeoColomb
11 years ago
parent
9a40054f78
commit
97ebbb5e75
@ -1,19 +1,194 @@
|
||||
This is the endoh entry from the 2012 International Obfuscated C Code Contest.
|
||||
# Most complex ASCII fluid - Honorable mention
|
||||
|
||||
tl;dr: it does ASCII fluid simulations.
|
||||
Yusuke Endoh
|
||||
<mame@tsg.ne.jp>
|
||||
|
||||
To run it:
|
||||
## Usage steps:
|
||||
|
||||
- git clone https://github.com/gardaud/endoh.git
|
||||
- cd endoh
|
||||
- make
|
||||
- ./endoh1 < pour-out.txt
|
||||
* `git clone https://github.com/LeoColomb/FluidASCII.git`
|
||||
* `cd endoh`
|
||||
* `make`
|
||||
* `./endoh1 < pour-out.txt`
|
||||
|
||||
You can also `make endoh1_color` and run this binary instead to get colored output.
|
||||
|
||||
Have fun :)
|
||||
## Author's comments:
|
||||
### Synopsis
|
||||
|
||||
Original code by Yusuke Endoh <mame@tsg.ne.jp>
|
||||
**DO NOT FORGET "-DG=1 -DP=4 -DV=8"** and make your terminal window larger
|
||||
than 80 x 25.
|
||||
|
||||
Original page here: http://www.ioccc.org/2012/endoh1/hint.html
|
||||
gcc endoh1.c -DG=1 -DP=4 -DV=8 -D_BSD_SOURCE -o endoh1 -lm
|
||||
./endoh1 < endoh1.c
|
||||
./endoh1 < logo.txt
|
||||
./endoh1 < column.txt
|
||||
./endoh1 < pour-out.txt
|
||||
./endoh1 < tanada.txt
|
||||
|
||||
|
||||
### What it is
|
||||
|
||||
,___. ,. ,. ,. ,___. ,. ,. ,.
|
||||
|/--' || `' || |/--' `' || |\_.
|
||||
|\__. || ,. ,. ,. ,__/| |\__. ,. ,____. ,. ,. || ,_. |/-' ,_. ,__.
|
||||
|/--' || || || || |/-\| `--\| || |/\/\| || || || ,/-\. || ,/-\. |/-\.
|
||||
|| || `\_/| || |\_/| ,__/| || |||||| `\_/| || `\_/\.`\_. `\_/' || `'
|
||||
`' `' `--' `' `---' `---' `' `'`'`' `--' `' `-'`' `-' `-' `'
|
||||
|
||||
|
||||
,.,. ,.,.
|
||||
,/\/\. ,. ,. ,. ,/\/\. ,. ,. ,__.
|
||||
|||#/' || `' ,_.|| |||#/' `',_.,__. || ||\\. ,.
|
||||
|||#\. || ,. ,. ,.,/#||| |\//\. ,.|#||##| ,. ,. || ,.,. |\/-' ,.,. ,.|\.
|
||||
|\/--' ||,/\.|| |||#/\/| `\#||| |||#||/\|,/\.|| ||,/'`\.|#| ,/'`\.|\/-\.
|
||||
`\| ||`\#||| |||#||\| ,//\/| ||`\|||||`\#||| ||`\.,/\/\|,.`\.,/'`\| `'
|
||||
`' `' `-'`' `'`-'`-' `-'`-' `' `'`'`' `-'`' `' `'`--'`'`' `'`' `'
|
||||
|
||||
|
||||
,_.,_. ,. ,. ,. ,_.,_. ,. ,. ,.
|
||||
|#||#| || `' || |#||#| `' || ||,_.
|
||||
||\/#| ||,. ,. ,.,_.,/| |\||#| ,.,_.,__.,. ,. || ,.,. |||#| ,.,. ,.,_.
|
||||
|||##| |||| || |||#||#| |#||#| |||#||##||| || ||,/||\.||`-',/||\.|||#\.
|
||||
||`--' ||`\_.|| |||\||#| |#||#| ||||'||\|`\_.|| ||`\||#|`\.,.`\||/'||`--'
|
||||
`' `' |#||| `'|#||#| |#||#| `'`' `'`' |#||| `' |||/' |||| |||| `'
|
||||
`-'`' `-'`-' `-'`-' `-'`' `'`' `'`' `'`'
|
||||
|
||||
|
||||
This program is a fluid simulator using "Smoothed-particle hydrodynamics (SPH)"
|
||||
method.
|
||||
|
||||
<http://en.wikipedia.org/wiki/Smoothed-particle_hydrodynamics>
|
||||
|
||||
The SPH particles represent the fluid flow. Particles have information about
|
||||
the position, density, and velocity. In every simulation step, they are
|
||||
changed by pressure force, viscosity force, and external force (i.e., gravity).
|
||||
|
||||
This program reads a text from standard input, and uses it as an initial
|
||||
configuration of the particles. The character `#` represents "wall particle" (a
|
||||
particle with fixed position), and any other non-space characters represent
|
||||
free particles.
|
||||
|
||||
The compilation options `-DG=1 -DP=4 -DV=8` represent, respectively, the factor
|
||||
of gravity, pressure, and viscosity. By changing their values, you can see
|
||||
different fluid behavior.
|
||||
|
||||
"Marching square"-like algorithm is used to render the particles.
|
||||
|
||||
<http://en.wikipedia.org/wiki/Marching_squares>
|
||||
|
||||
|
||||
### Portability
|
||||
|
||||
The program requires a C99 compiler; it uses `complex` types and one-line
|
||||
comments. It also uses `usleep`, which may require `-D_BSD_SOURCE` or somewhat
|
||||
to build with no warning. Under these conditions, it should be portable.
|
||||
At least, recent compilers with `-std=c99 -Wall -W -Wextra -pedantic` says
|
||||
nothing.
|
||||
|
||||
gcc -DG=1 -DP=4 -DV=8 -D_BSD_SOURCE -std=c99 -Wall -W -Wextra -pedantic endoh1.c
|
||||
clang -DG=1 -DP=4 -DV=8 -D_BSD_SOURCE -std=c99 -Wall -W -Wextra -pedantic endoh1.c
|
||||
|
||||
I expect it to work in any Unix-like environment. VTxxx/ANSI sequences are
|
||||
used to clear screen and move cursor to home.
|
||||
|
||||
I've tested with gcc-4.6.3 and clang-3.0 on Linux (Ubuntu 12.04)
|
||||
and gcc-4.5.3 and clang-3.1 on Cygwin. On Cygwin, gcc and clang complain about
|
||||
a usage of `I` (complex's imaginary unit), but I bet this is cygwin's issue;
|
||||
it is surely a C99 feature.
|
||||
|
||||
|
||||
### Obfuscation w/ Spoiler
|
||||
|
||||
First of all, the source code itself serves as an initial configuration.
|
||||
Preprocessing directives (such as `#include`)'s `#` serve as walls.
|
||||
|
||||
This program uses `double complex` to represent any 2D vector. But, note that
|
||||
x-axis and y-axis is swapped (real axis = y-axis, imaginary axis = x-axis).
|
||||
The purpose of swapping is not only obfuscation, but also short coding: for
|
||||
example, to add gravity to total force, `force += G` suffices, rather than
|
||||
`force += G*I`.
|
||||
(Incidentally, you can exert horizontal gravity by using, such as, `-DG=I`)
|
||||
|
||||
Every five entries of `double complex a[]` contain information of one particle:
|
||||
position, wall-flag, density, force, and velocity, in turn.
|
||||
|
||||
You can use `G`, `P`, and `V` as a guide to find the calculation code of
|
||||
gravity, pressure, and viscosity forces.
|
||||
|
||||
Though some assignments may look meaningless, it is actually meaningful; it
|
||||
extracts "integer part of real part" from a complex value by assigning (and
|
||||
casting) it to an integer-type variable.
|
||||
|
||||
|
||||
### Notes about Additional Files
|
||||
|
||||
"logo.txt" is a source of the logo in this remark file.
|
||||
|
||||
"column.txt" is a water column collapse, which is a popular demo of SPH.
|
||||
|
||||
"pour-out.txt" pours you a cup of tea.
|
||||
|
||||
"tanada.txt" simulates "Terrace farming". ("Tanada" means a "terraced rice
|
||||
fields" in Japanese.)
|
||||
|
||||
"clock.txt" is a "water" clock created by HAMANO Tsukasa.
|
||||
|
||||
Other \*.txt files are due to the judges.
|
||||
|
||||
|
||||
"endoh1\_color.c" is a variant that shows the density by using terminal 256
|
||||
colors.
|
||||
|
||||
|
||||
### Acknowledgment
|
||||
|
||||
I would like to thank my wife @hirekoke for her teaching me the SPH method.
|
||||
|
||||
The judges <strike>ordered</strike> suggested creating a color version
|
||||
after the judgment.
|
||||
|
||||
The judges and HAMANO Tsukasa (The silver medalist at this IOCCC) kindly
|
||||
provided many configuration files.
|
||||
|
||||
|
||||
## Judges' comments:
|
||||
### To build:
|
||||
|
||||
make endoh1
|
||||
|
||||
### To run:
|
||||
|
||||
./endoh1 < configuration.txt
|
||||
|
||||
### Try:
|
||||
|
||||
./endoh1 < endoh1.c
|
||||
|
||||
./endoh1 < pour-out.txt
|
||||
|
||||
./endoh1 < fountain.txt
|
||||
|
||||
### Selected Judges Remarks:
|
||||
|
||||
Let's play Jeopardy!
|
||||
|
||||
* A: An obfuscated program that deals with complex numbers and produces animated ASCII graphics.
|
||||
* Q: What is a Mandelbrot simulator?
|
||||
|
||||
Bzzzt!
|
||||
|
||||
Such heavily squeezed fluid simulation (this is parsed uniquely
|
||||
as fluids are not squeezable) has a few quirks that the judges were
|
||||
happy to experiment with.
|
||||
|
||||
One configuration file was inspired by an [XKCD what if? entry](http://whatif.xkcd.com/6/).
|
||||
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
<!--
|
||||
(c) Copyright 1984-2012, [Leo Broukhis, Simon Cooper, Landon Curt Noll][judges] - All rights reserved
|
||||
This work is licensed under a [Creative Commons Attribution-ShareAlike 3.0 Unported License][cc].
|
||||
|
||||
[judges]: http://www.ioccc.org/judges.html
|
||||
[cc]: http://creativecommons.org/licenses/by-sa/3.0/
|
||||
-->
|
||||
|
||||
@ -1,184 +0,0 @@
|
||||
# Most complex ASCII fluid - Honorable mention
|
||||
|
||||
Yusuke Endoh
|
||||
<mame@tsg.ne.jp>
|
||||
|
||||
|
||||
## Judges' comments:
|
||||
### To build:
|
||||
|
||||
make endoh1
|
||||
|
||||
### To run:
|
||||
|
||||
./endoh1 < configuration.txt
|
||||
|
||||
### Try:
|
||||
|
||||
./endoh1 < endoh1.c
|
||||
|
||||
./endoh1 < pour-out.txt
|
||||
|
||||
./endoh1 < fountain.txt
|
||||
|
||||
### Selected Judges Remarks:
|
||||
|
||||
Let's play Jeopardy!
|
||||
|
||||
* A: An obfuscated program that deals with complex numbers and produces animated ASCII graphics.
|
||||
* Q: What is a Mandelbrot simulator?
|
||||
|
||||
Bzzzt!
|
||||
|
||||
Such heavily squeezed fluid simulation (this is parsed uniquely
|
||||
as fluids are not squeezable) has a few quirks that the judges were
|
||||
happy to experiment with.
|
||||
|
||||
One configuration file was inspired by an [XKCD what if? entry](http://whatif.xkcd.com/6/).
|
||||
|
||||
## Author's comments:
|
||||
### Synopsis
|
||||
|
||||
**DO NOT FORGET "-DG=1 -DP=4 -DV=8"** and make your terminal window larger
|
||||
than 80 x 25.
|
||||
|
||||
gcc endoh1.c -DG=1 -DP=4 -DV=8 -D_BSD_SOURCE -o endoh1 -lm
|
||||
./endoh1 < endoh1.c
|
||||
./endoh1 < logo.txt
|
||||
./endoh1 < column.txt
|
||||
./endoh1 < pour-out.txt
|
||||
./endoh1 < tanada.txt
|
||||
|
||||
|
||||
### What it is
|
||||
|
||||
,___. ,. ,. ,. ,___. ,. ,. ,.
|
||||
|/--' || `' || |/--' `' || |\_.
|
||||
|\__. || ,. ,. ,. ,__/| |\__. ,. ,____. ,. ,. || ,_. |/-' ,_. ,__.
|
||||
|/--' || || || || |/-\| `--\| || |/\/\| || || || ,/-\. || ,/-\. |/-\.
|
||||
|| || `\_/| || |\_/| ,__/| || |||||| `\_/| || `\_/\.`\_. `\_/' || `'
|
||||
`' `' `--' `' `---' `---' `' `'`'`' `--' `' `-'`' `-' `-' `'
|
||||
|
||||
|
||||
,.,. ,.,.
|
||||
,/\/\. ,. ,. ,. ,/\/\. ,. ,. ,__.
|
||||
|||#/' || `' ,_.|| |||#/' `',_.,__. || ||\\. ,.
|
||||
|||#\. || ,. ,. ,.,/#||| |\//\. ,.|#||##| ,. ,. || ,.,. |\/-' ,.,. ,.|\.
|
||||
|\/--' ||,/\.|| |||#/\/| `\#||| |||#||/\|,/\.|| ||,/'`\.|#| ,/'`\.|\/-\.
|
||||
`\| ||`\#||| |||#||\| ,//\/| ||`\|||||`\#||| ||`\.,/\/\|,.`\.,/'`\| `'
|
||||
`' `' `-'`' `'`-'`-' `-'`-' `' `'`'`' `-'`' `' `'`--'`'`' `'`' `'
|
||||
|
||||
|
||||
,_.,_. ,. ,. ,. ,_.,_. ,. ,. ,.
|
||||
|#||#| || `' || |#||#| `' || ||,_.
|
||||
||\/#| ||,. ,. ,.,_.,/| |\||#| ,.,_.,__.,. ,. || ,.,. |||#| ,.,. ,.,_.
|
||||
|||##| |||| || |||#||#| |#||#| |||#||##||| || ||,/||\.||`-',/||\.|||#\.
|
||||
||`--' ||`\_.|| |||\||#| |#||#| ||||'||\|`\_.|| ||`\||#|`\.,.`\||/'||`--'
|
||||
`' `' |#||| `'|#||#| |#||#| `'`' `'`' |#||| `' |||/' |||| |||| `'
|
||||
`-'`' `-'`-' `-'`-' `-'`' `'`' `'`' `'`'
|
||||
|
||||
|
||||
This program is a fluid simulator using "Smoothed-particle hydrodynamics (SPH)"
|
||||
method.
|
||||
|
||||
<http://en.wikipedia.org/wiki/Smoothed-particle_hydrodynamics>
|
||||
|
||||
The SPH particles represent the fluid flow. Particles have information about
|
||||
the position, density, and velocity. In every simulation step, they are
|
||||
changed by pressure force, viscosity force, and external force (i.e., gravity).
|
||||
|
||||
This program reads a text from standard input, and uses it as an initial
|
||||
configuration of the particles. The character `#` represents "wall particle" (a
|
||||
particle with fixed position), and any other non-space characters represent
|
||||
free particles.
|
||||
|
||||
The compilation options `-DG=1 -DP=4 -DV=8` represent, respectively, the factor
|
||||
of gravity, pressure, and viscosity. By changing their values, you can see
|
||||
different fluid behavior.
|
||||
|
||||
"Marching square"-like algorithm is used to render the particles.
|
||||
|
||||
<http://en.wikipedia.org/wiki/Marching_squares>
|
||||
|
||||
|
||||
### Portability
|
||||
|
||||
The program requires a C99 compiler; it uses `complex` types and one-line
|
||||
comments. It also uses `usleep`, which may require `-D_BSD_SOURCE` or somewhat
|
||||
to build with no warning. Under these conditions, it should be portable.
|
||||
At least, recent compilers with `-std=c99 -Wall -W -Wextra -pedantic` says
|
||||
nothing.
|
||||
|
||||
gcc -DG=1 -DP=4 -DV=8 -D_BSD_SOURCE -std=c99 -Wall -W -Wextra -pedantic endoh1.c
|
||||
clang -DG=1 -DP=4 -DV=8 -D_BSD_SOURCE -std=c99 -Wall -W -Wextra -pedantic endoh1.c
|
||||
|
||||
I expect it to work in any Unix-like environment. VTxxx/ANSI sequences are
|
||||
used to clear screen and move cursor to home.
|
||||
|
||||
I've tested with gcc-4.6.3 and clang-3.0 on Linux (Ubuntu 12.04)
|
||||
and gcc-4.5.3 and clang-3.1 on Cygwin. On Cygwin, gcc and clang complain about
|
||||
a usage of `I` (complex's imaginary unit), but I bet this is cygwin's issue;
|
||||
it is surely a C99 feature.
|
||||
|
||||
|
||||
### Obfuscation w/ Spoiler
|
||||
|
||||
First of all, the source code itself serves as an initial configuration.
|
||||
Preprocessing directives (such as `#include`)'s `#` serve as walls.
|
||||
|
||||
This program uses `double complex` to represent any 2D vector. But, note that
|
||||
x-axis and y-axis is swapped (real axis = y-axis, imaginary axis = x-axis).
|
||||
The purpose of swapping is not only obfuscation, but also short coding: for
|
||||
example, to add gravity to total force, `force += G` suffices, rather than
|
||||
`force += G*I`.
|
||||
(Incidentally, you can exert horizontal gravity by using, such as, `-DG=I`)
|
||||
|
||||
Every five entries of `double complex a[]` contain information of one particle:
|
||||
position, wall-flag, density, force, and velocity, in turn.
|
||||
|
||||
You can use `G`, `P`, and `V` as a guide to find the calculation code of
|
||||
gravity, pressure, and viscosity forces.
|
||||
|
||||
Though some assignments may look meaningless, it is actually meaningful; it
|
||||
extracts "integer part of real part" from a complex value by assigning (and
|
||||
casting) it to an integer-type variable.
|
||||
|
||||
|
||||
### Notes about Additional Files
|
||||
|
||||
"logo.txt" is a source of the logo in this remark file.
|
||||
|
||||
"column.txt" is a water column collapse, which is a popular demo of SPH.
|
||||
|
||||
"pour-out.txt" pours you a cup of tea.
|
||||
|
||||
"tanada.txt" simulates "Terrace farming". ("Tanada" means a "terraced rice
|
||||
fields" in Japanese.)
|
||||
|
||||
"clock.txt" is a "water" clock created by HAMANO Tsukasa.
|
||||
|
||||
Other \*.txt files are due to the judges.
|
||||
|
||||
|
||||
"endoh1\_color.c" is a variant that shows the density by using terminal 256
|
||||
colors.
|
||||
|
||||
|
||||
### Acknowledgment
|
||||
|
||||
I would like to thank my wife @hirekoke for her teaching me the SPH method.
|
||||
|
||||
The judges <strike>ordered</strike> suggested creating a color version
|
||||
after the judgment.
|
||||
|
||||
The judges and HAMANO Tsukasa (The silver medalist at this IOCCC) kindly
|
||||
provided many configuration files.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
<!--
|
||||
(c) Copyright 1984-2012, [Leo Broukhis, Simon Cooper, Landon Curt Noll][judges] - All rights reserved
|
||||
This work is licensed under a [Creative Commons Attribution-ShareAlike 3.0 Unported License][cc].
|
||||
|
||||
[judges]: http://www.ioccc.org/judges.html
|
||||
[cc]: http://creativecommons.org/licenses/by-sa/3.0/
|
||||
-->
|
||||
Loading…
Reference in New Issue