ORCΛ

Each letter of the alphabet is an operation, lowercase letters typically operate on bang(*), uppercase letters operate on each frame. Bangs can be generated by various operations, such as E colliding with a 0, see the bang.orca example. Watch a music video of ORCΛ in action.

C Port for the ORCΛ programming environment, with a commandline interpreter.

Prerequisites

Core library: A C99 compiler (no VLAs required), plus enough libc for malloc, realloc, free, memcpy, memset, and memmove.

Command-line interpreter: The above, plus POSIX, and enough libc for the common string operations (strlen, strcmp, etc.)

Interactive terminal UI: The above, plus ncurses (or compatible curses library).

Build

The build script is in bash. It should work with gcc (including the musl-gcc wrapper) and clang, and will automatically detect your compiler.

Currently known to build on macOS (gcc, clang) and Linux (gcc, musl-gcc, and clang, optionally with LLD).

Not yet tested on Windows, but it's likely that it already works under cygwin. Further testing will be performed soon.

There is a fire-and-forget make wrapper around the build script.

Make

make debug      # debugging build, binary placed at build/debug/orca
make release    # optimized build, binary placed at build/release/orca
make clean      # removes build/

Build Script

Run ./tool --help to see usage info. Examples:

./tool -c clang-7 build release orca
    # build the terminal ui with a compiler named
    # clang-7, with optimizations enabled.
    # binary placed at build/release/orca

./tool build debug cli
    # debug build of the headless CLI interpreter
    # binary placed at build/debug/cli

./tool clean
    # same as make clean, removes build/

Run

Interactive terminal UI

orca [options] [file]

Run the interactive terminal UI, useful for debugging or observing behavior. Pass -h or --help to see command-line argument usage.

Controls

• ctrl+q: quit
• Arrow keys or ctrl+h/j/k/l: move cursor
• A-Z, a-z, 0-9, and other printable characters: write character to grid at cursor
• Spacebar: play or pause
• ctrl+f: step the simulation one tick forward
• ctrl+u: undo
• return or enter: change into or out of overwrite/append mode
• /: change into or out of key-trigger mode (for the ! operator)
• [ and ]: Adjust cosmetic grid rulers horizontally
• { and }: Adjust cosmetic grid rulers vertically
• ( and ): resize grid horizontally
• _ and +: resize grid vertically

CLI interpreter

The CLI (cli binary) reads from a file and runs the orca simulation for 1 timestep (default) or a specified number (-t option) and writes the resulting state of the grid to stdout.

cli [-t timesteps] infile

You can also make cli read from stdin:

echo -e "...\na34\n..." | cli /dev/stdin

Extras

• Support this project through Patreon.
• See the License file for license rights and limitations (MIT).
• Pull Requests are welcome!