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), and floating point support (for timing.)

Note: the core library for running an orca virtual machine should in theory build on anything, but the project is being worked on quickly right now, so it might accidentally include something from POSIX that isn't available on Windows, for example. The header files also need some restructuring. Please open an issue or send a message on twitter if you need help building the core virtual machine for your own use, and I'll try to clean it up for you.

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), and Windows via cygwin or WSL (gcc or clang).

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+z or ctrl+u: undo
• ctrl+x: cut
• ctrl+c: copy
• ctrl+v: paste
• ctrl+s: save
• ctrl+d or F1: open main menu
• return or enter: change into or out of overwrite/append mode
• /: change into or out of key-trigger mode (for the ! operator)
• ' (single quote): change into or out of rectangle selection size adjustment mode
• shift+arrow keys: adjust rectangle selection size (only in some terminals)
• escape: return to normal mode, or deselect (set cursor rectangle selection to 1x1)
• [ and ]: adjust cosmetic grid rulers horizontally
• { and }: adjust cosmetic grid rulers vertically
• ( and ): resize grid horizontally
• _ and +: resize grid vertically
• < and >: adjust BPM

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!