line is drawn horizontally on the screen.
Over time, this line of cells evolves according to rules, with some cells
-switching on or off. Each new iteration is drawn below its predecessor, leading
-the screen to scroll vertically over time.
+switching on or off. Each new application of the rule to the universe is drawn
+on the screen as a new line directly below the previous generation's line,
+leading the screen to scroll vertically.
-The rules which govern the time evolution of this system depend only on the
-current state of a given cell and the state of its two immediate neighbors.
-These rules are formalized as
+Since these are "elementary" cellular automata, the rules which govern the time
+evolution of this system depend only on the current state of a given cell and
+the state of its two immediate neighbors. These rules are formalized as
[Wolfram codes](https://en.wikipedia.org/wiki/Wolfram_code),
where the code number is directly convertible into a rule set.
![Rule 110 Animated Screenshot](/screensavers/.git/blob_plain/HEAD:/hacks/WolframAutomata/screenshot_rule_110.gif)
-Commandline flags are provided enabling the user to tweak attributes such as
-length and speed of simulation, cell size, rule number, colors, starting seed,
-and other attributes. For example, the screenshot below depicts Rule 73 with
-different colors than the Rule 110 screenshot. Like the Rule 110 screenshot, it
-uses `-cell-size 2` and seeds the simulation with only a single active cell.
+Commandline flags are provided which enable the user to tweak attributes such
+as length and speed of simulation, cell size, rule number, colors, starting
+seed, and other attributes. For example, the screenshot below depicts Rule 73
+with different colors than the Rule 110 screenshot. Like the Rule 110
+screenshot, it uses `-cell-size 2` and seeds the simulation with only a single
+active cell.
![Rule 73 Animated Screenshot](/screensavers/.git/blob_plain/HEAD:/hacks/WolframAutomata/screenshot_rule_73.gif)
that file. Note that the `Makefile` assumes a copy of the screenhack library
source code is located at `../screenhack/` relative to this directory.
-For assistance setting `$(DEFINES)` on non-FreeBSD platforms, consider
-downloading the XScreensaver source tarball, running `./configure` in the
-unpacked directory, and examining the resulting `config.h` file.
+For assistance setting `$(DEFINES)` in the `Makefile` on non-FreeBSD platforms,
+consider downloading the XScreensaver source tarball, running `./configure` in
+the unpacked directory, and examining the resulting `config.h` file.
Although WolframAutomata can integrate with XScreensaver, the presence of
XScreensaver is not strictly required. WolframAutomata will both build and
simulation completes or after resizing the window.
+CLI: Rule Selection
+-------------------
+
+If neither of the following two options are passed, rules are randomly selected
+from `curated_ruleset_list[]` in `WolframAutomata.c`.
+
+ - **`-true-random-rule`**: Select a rule completely at random, NOT randomly
+ from a curated list. Note that many rules are visually uninteresting.
+
+ - **`-rule N`**: Select a specific rule where `N` is a Wolfram number. Values
+ from 0-255 inclusive are valid.
+
+
CLI: Simulation Seed
--------------------
-If none of the following options are specified, the starting seed will contain
-randomly interspersed active/inactive cells at a 30/70, 50/50, or 70/30 ratio,
-itself also randomly selected.
+The following seed related CLI flags apply only when using the
+`-true-random-rule` or `-rule N` flags. Without these flags, the program draws
+rules from `curated_ruleset_list[]` which also includes curated seeds, all of
+which override any seed related CLI flags.
+
+If the curated rule list is not in use and none of the following options are
+specified, the starting seed will contain randomly interspersed active/inactive
+cells at a 30/70, 50/50, or 70/30 ratio, itself also randomly selected.
- **`-seed-left`**: Seeds a single active cell on the left side of the
display. All other cells are inactive.
- **`-seed-density N`**: Generates random seed with `N` percent active cells.
-CLI: Rule Selection
--------------------
+CLI: Simulation Length
+----------------------
-If neither of the following two options are passed, rules are randomly selected
-from `curated_ruleset_list[]` in `WolframAutomata.c`.
+If neither of the following two options are passed, the simulation runs as
+though `-length 5000` was passed.
- - **`-true-random-rule`**: Select a rule completely at random, NOT randomly
- from a curated list. Note that many rules are visually uninteresting.
+ - **`-random-length`**: A random length smaller than 10,000 generations but
+ large enough to fill the screen is selected.
- - **`-rule N`**: Select a specific rule where `N` is a Wolfram number. Values
- from 0-255 inclusive are valid.
+ - **`-length N`**: Request `N` generations be simulated on each run.
+
+Note that an upper limit of 10,000 generations is enforced in order to avoid
+`BadAlloc` errors from some X servers. For more details, read
+`WolframAutomata.c` starting around the comment, "The maximum number of
+generations is cell_size dependent. This is a soft limit and may be increased
+if ..."
CLI: Simulation Speed
well respected.
-CLI: Simulation Length
-----------------------
-
-If neither of the following two options are passed, the simulation runs as
-thought `-length 5000` was passed.
-
- - **`-random-length`**: A random length smaller than 10,000 generations but
- large enough to fill the screen is selected.
-
- - **`-length N`**: Request `N` generations be simulated on each run.
-
-Note that an upper limit of 10,000 generations is enforced in order to avoid
-`BadAlloc` errors from some X servers. For more details, read
-`WolframAutomata.c` starting around the comment, "The maximum number of
-generations is cell_size dependent. This is a soft limit and may be increased
-if ..."
-
-
CLI: Cell Dimensions
--------------------
git clone git://git.subgeniuskitty.com/screensavers
cd screensavers/hacks/WolframAutomata
make clean all
- cp WolframAutomata /usr/local/bin/xscreensaver-hacks/
+ cp WolframAutomata /usr/local/bin/xscreensaver-hacks/wolframautomata
-Now create the file `WolframAutomata.xml` wherever your system stores
+Now create the file `wolframautomata.xml` wherever your system stores
XScreensaver config files and populate it with the contents shown below. For
example, on FreeBSD:
- vi /usr/local/share/xscreensaver/config/WolframAutomata.xml
-
- TODO: Finish writing this file after the command line options are finalized.
+ vi /usr/local/share/xscreensaver/config/wolframautomata.xml
+
+ <?xml version="1.0" encoding="ISO-8859-1"?>
+
+ <screensaver name="wolframautomata" _label="WolframAutomata">
+
+ <command arg="-root"/>
+
+ <string id="rule_number" _label="Rule number: " arg="-rule %" />
+ <boolean id="rnd_rule" _label="Random rule" arg-set="-random-rule" />
+
+ <string id="seed_density" _label="Seed density (%):" arg="-seed-density %" />
+ <boolean id="seed_left" _label="Seed left" arg-set="-seed-left" />
+ <boolean id="seed_center" _label="Seed center" arg-set="-seed-center" />
+ <boolean id="seed_right" _label="Seed right" arg-set="-seed-right" />
+
+ <string id="length" _label="Length (gen):" arg="-length %" />
+ <boolean id="rnd_length" _label="Random length" arg-set="-random-length" />
+
+ <string id="delay" _label="Delay (usec):" arg="-delay %" />
+ <boolean id="rnd_delay" _label="Random delay" arg-set="-random-delay" />
+
+ <string id="cell_size" _label="Cell size (px):" arg="-cell-size %" />
+ <boolean id="rnd_cellsize" _label="Random cell size" arg-set="-random-cell-size" />
+
+ <string id="color_index" _label="Color index (int):" arg="-color-index %" />
+
+ <string id="admiration" _label="Admiration (sec):" arg="-admiration-delay %" />
+
+ <_description>
+ Displays the time evolution of elementary cellular automata.
+
+ These automata consist of a line of cells, each of which may be either on or
+ off. To ensure every cell has neighbors, the two endpoints of the line connect
+ together, thereby forming a circular universe for the cells to inhabit. This
+ line is drawn horizontally on the screen.
+
+ Over time, this line of cells evolves according to rules, with some cells
+ switching on or off. Each new iteration is drawn below its predecessor,
+ leading the screen to scroll vertically over time.
+
+ The rules which govern the time evolution of this system depend only on the
+ current state of a given cell and the state of its two immediate neighbors.
+ These rules are formalized as Wolfram codes, where the code number is directly
+ convertible into a rule set.
+ </_description>
+ </screensaver>
The next step integrates WolframAutomata into an individual user's XScreensaver
config via the file `~/.xscreensaver`. If preferred, it could instead be done
xplanet -vroot -wait 1 -timewarp 400 \
-label -origin moon \n\
GL: fireflies -root \n\
- WolframAutomata -root \n\
+ wolframautomata -root \n\
blitspin -root \n\
<snip>