X-Git-Url: http://git.subgeniuskitty.com/screensavers/.git/blobdiff_plain/74edf5615df795383c222e83aa53894114dfd193..6b4b1b563ebbd3ddc4069eff5e56a260f2e92828:/hacks/WolframAutomata/README.md diff --git a/hacks/WolframAutomata/README.md b/hacks/WolframAutomata/README.md index fd091a7..d3546d1 100644 --- a/hacks/WolframAutomata/README.md +++ b/hacks/WolframAutomata/README.md @@ -35,15 +35,11 @@ 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) In situations where true randomness would lead to visually unappealing -displays, this program provides random selection from curated lists. For +displays, this program provides random selection from curated lists. As one example, to avoid randomly selecting visually indistinguishable colors like `dark red` and `brown` to depict on/off cells, the program includes a pre-selected list of color pairs that complement each other and chooses -randomly from this list when the `-random-color` flag is passed. Similarly, to -avoid the visually uninteresting rules like rule 0, a rule which simply turns -every cell off and keeps it off, the program includes a list of rulesets and -starting seeds which are visually appealing, selecting randomly from this list -when the `-random-rule` flag is passed. +randomly from this list. Status @@ -75,3 +71,205 @@ 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 execute using only the included screenhack library. + + +Command-Line Flags +================== + +Whenever related options exist, such as the following two rule-selection +options, the related options are listed in order of precedence. + +Where flags instruct the program to make random selections, these selections +are re-randomized every time the simulation is reset, such as after a +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 +-------------------- + +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-center`**: As above, but in the center. + + - **`-seed-right`**: As above, but on the right side. + + - **`-seed-density N`**: Generates random seed with `N` percent active cells. + + +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: Simulation Speed +--------------------- + +If neither of the following two options are passed, the simulation runs as +though `-delay 25000` was passed. + + - **`-random-delay`**: A random delay is selected, but not truly random. For + more details, read `WolframAutomata.c` starting around the comment, "When + randomly setting the delay, the problem is to avoid ..." + + - **`-delay N`**: Request `N` microsecond delay between each frame/generation + of the simulation. Note that this is only a request; XScreensaver reserves + the right to ignore requested values, and of course we execute at the mercy + of the kernel's scheduling. In practice, non-absurd values are reasonably + well respected. + + +CLI: Cell Dimensions +-------------------- + +Individual cells may be displayed as any square number of pixels (e.g. 1x1, +2x2, etc). Increasing the cell size may help with flickering on high DPI +monitors displaying chaotic rulesets. + +If neither of the following two options are passed, the simulation behaves as +though `-cell-size 2` was passed. + + - **`-random-cell-size`**: Randomly selects 1, 2, 4, 8, 16, or 32 as the cell + size on each reset of the simulation. + + - **`-cell-size N`**: Display each individual cell as an `N`x`N` square of + pixels on the screen. + + +CLI: Color +---------- + +At the moment, the program does not allow the user to specify raw RGB values +from the command line. Instead, color pairs are selected from `color_list[]` +in `WolframAutomata.c` by specifying an index (starting from `0`) into this +array. However, any RGB color the user desires may be added by creating new +entries in that array (or editing existing entries) and recompiling. + +If the following CLI option is not passed, a random color selection is made +from `color_list[]` at the start of each new simulation run. + + - **`-color-index N`**: Select color pair `N` from `color_list[]` in + `WolframAutomata.c`. + +Note that the names provided as comments in `color_list[]` are X11 color names. + + +CLI: Admiration +--------------- + +When the simulation reaches its end as determined by flags like `-length N` it +will pause for a period of time, allowing the viewer to examine it without +interference from scrolling. By default, this 'admiration window' is five +seconds long. + + - **`-admiration-delay N`**: At the end of a simulation, pause for `N` + seconds before resetting for the next simulation. + + +XScreensaver Integration +======================== + +In addition to running as a standalone program, WolframAutomata can be +integrated into the XScreensaver framework. + +To accomplish this integration, begin by installing and configuring +XScreensaver via whatever method is appropriate for your operating system. The +following instructions assume the filesystem paths used by FreeBSD packages and +ports; your paths may differ. After XScreensaver installation, ensure all +pertinent config files are created by running `xscreensaver-demo` and +configuring XScreensaver for your system. + +After XScreensaver is configured and working on your system, ensure that +WolframAutomata runs in standalone mode on your system. If you can `make clean run` +in the `screensavers/hacks/WolframAutomata/` folder and see the hack's visual +output, you're ready to move on. + +At this point, copy the hack into your XScreensaver hack directory. For +example, with prerequisite steps spelled out: + + git clone git://git.subgeniuskitty.com/screensavers + cd screensavers/hacks/WolframAutomata + make clean all + cp WolframAutomata /usr/local/bin/xscreensaver-hacks/ + +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. + +The next step integrates WolframAutomata into an individual user's XScreensaver +config via the file `~/.xscreensaver`. If preferred, it could instead be done +in the global XScreensaver config. + +In the `~/.xscreensaver` file, create a WolframAutomata entry under the +`programs:` label in the same list as all the other hacks. Position in the +list is irrelevant, but ensure you don't paste WolframAutomata's entry into the +middle of pre-existing, multi-line entries. For context, the example below +includes a multi-line entry, a GL entry and a plain entry. All that is needed +is to insert the WolframAutomata line somewhere in the `programs:` list, as +demonstrated. + + vi ~/.xscreensaver + + + programs: \ + xplanet -vroot -wait 1 -timewarp 400 \ + -label -origin moon \n\ + GL: fireflies -root \n\ + WolframAutomata -root \n\ + blitspin -root \n\ + + +That's all. Now you can run `xscreensaver-demo` and select WolframAutomata just +like any other hack. + + +Screen Tearing +============== + +Certain combinations of rules and display settings lead to full screen vertical +scrolling of alternating light and dark pixels, or other difficult to display +patterns. If your display doesn't include some type of vertical refresh +synchronization, such output will look terrible. + +If stuck in this situation, changing the output of WolframAutomata to scroll +horizontally may help, or simply increasing the cell size. +