- From a chunky ASCII-art source drawing, render polished, graphically-rich SVG, with the goat CLI command.
-
Tie together all three of:
- Your code's major data structures or abstract data/control flows.
- Related ASCII-art diagrams embedded in comments, adjacent to the source code.
- Polished line diagrams in your user-facing high-level documentation, with inline links to SVG produced by goat. For Markdown or similar formats, links may be expanded either at build-time or run-time, as needed by your doc tool suite.
Your ASCII-art source persists as the single-point-of-truth, revision-controlled along with the code that embeds it. This README contains an example.
Both vim and emacs offer useful support.
In Emacs, see the built-in rectangle-editing commands, and picture-mode.
Most fixed-pitch or "monospace" Unicode fonts maintain a 2:1 aspect ratio for characters in the ASCII range, and all GoAT drawing characters are ASCII. However, certain Unicode graphical characters e.g. MIDDLE DOT may be useful, and conform to the width of the ASCII range.
CJK characters on the other hand are typically wider than 2:1. Non-standard width characters are not in general composable on the left-right axis within a plain-text drawing, because the remainder of the line of text to their right is pushed out of alignment with rows above and below.
$ go install github.com/blampe/goat/cmd/goat@latest
Here are some snippets of
GoAT-formatted UTF-8
and the SVG each can generate.
The SVG you see below was linked to by
inline Markdown image references
(howto,
spec) from
GoAT's README.md, then finally rendered to HTML <img> elements by Github's Markdown processor
. . . .--- 1 .-- 1 / 1
/ \ | | .---+ .-+ +
/ \ .---+---. .--+--. | '--- 2 | '-- 2 / \ 2
+ + | | | | ---+ ---+ +
/ \ / \ .-+-. .-+-. .+. .+. | .--- 3 | .-- 3 \ / 3
/ \ / \ | | | | | | | | '---+ '-+ +
1 2 3 4 1 2 3 4 1 2 3 4 '--- 4 '-- 4 \ 4
Setting a foreground color in the middle of the possible range of value or luminance
is one way to work around a limitation of certain browsers e.g. Safari.
Safari does not support inheritance of
the color-scheme
CSS property by
goat's output <svg> element
from within an enclosing <img> element such as are generated by Markdown.
.-. .-. .-. .-. .-. .-.
| | | | | | | | | | | |
.---------. .--+---+--. .--+---+--. .--| |--. .--+ +--. .------|--.
| | | | | | | | | | | | | | | | | |
'---------' '--+---+--' '--+---+--' '--| |--' '--+ +--' '--|------'
| | | | | | | | | | | |
'-' '-' '-' '-' '-' '-'
________ o * * .--------------.
*---+--. | | o o | ^ \ / | .----------. |
| | '--* -+- | | v / \ / | | <------. | |
| '-----> .---(---' --->*<--- / .+->*<--o----' | | | | |
<--' ^ ^ | | | | | ^ \ | '--------' | |
\/ *-----' o |<----->| '-----' |__| v '------------' |
/\ *---------------'
o--o *--o / / * o o o o o * * * * o o o o * * * * o o o o * * * *
o--* *--* v v ^ ^ | | | | | | | | \ \ \ \ \ \ \ \ / / / / / / / /
o--> *--> * o / / o * v ' o * v ' o * v \ o * v \ o * v / o * v /
o--- *---
^ ^ ^ ^ . . . . ^ ^ ^ ^ \ \ \ \ ^ ^ ^ ^ / / / /
| | * o \ \ * o | | | | | | | | \ \ \ \ \ \ \ \ / / / / / / / /
v v ^ ^ v v ^ ^ o * v ' o * v ' o * v \ o * v \ o * v / o * v /
* o | | * o \ \
<--o <--* <--> <--- ---o ---* ---> ---- *<-- o<-- -->o -->*
o o o o o * * * * * * * o o * o o o * * * o o o · * · · · · · ·
o o o o o * * * * * o o o o * o o o o * * * * * o * * · * * · · · · · ·
o o o o o * * * * * o * o o o o o o o o * * * * * o o o o o · o · · o · · * * ·
o o o o o * * * * * o * o o o o o o o * * * * o * o o · · · · o · · * ·
o o o o o * * * * * * * * * o o o o * * * o * o · · · · · · · *
Note that '·' above is not ASCII, but rather Unicode, the MIDDLE DOT character, encoded with UTF-8.
.---. .-. .-. .-. .-.
| A +----->| 1 +<---->| 2 |<----+ 4 +------------------. | 8 |
'---' '-' '+' '-' | '-'
| ^ | ^
v | v |
.-. .-+-. .-. .-+-. .-. .+. .---.
| 3 +---->| B |<----->| 5 +---->| C +---->| 6 +---->| 7 |<---->| D |
'-' '---' '-' '---' '-' '-' '---'
___ ___ .---+---+---+---+---. .---+---+---+---.
___/ \___/ \ | | | | | | / \ / \ / \ / \ /
/ \___/ \___/ +---+---+---+---+---+ +---+---+---+---+
\___/ b \___/ \ | | | b | | | \ / \a/ \b/ \ / \
/ a \___/ \___/ +---+---+---+---+---+ +---+---+---+---+
\___/ \___/ \ | | a | | | | / \ / \ / \ / \ /
\___/ \___/ '---+---+---+---+---' '---+---+---+---'
.---. .---. +--+ +-+ +-+ .-. .--. .-. +-+ +--+ .-. .--.
| | | | | | | | | | | | | | | | | | | | | | | |
+---+ +---+ +--+ +-+ | | | | | | | | +-+ +--+ '-' '--'
| +---+ | | | | | | | | | | | | |
+---+ b +---+ +--+ +-+ | | | | | | | |
| a +---+ | | | | | | | | | | | | |
'---' '---' +--+ +-+ +-+ '-' '--' '-'
+---+ .---. .---.
| B | | E | | F |
+---+ '---' '---'
.---. +---+ .---.
| D | | G | | H |
'---' +---+ '---'
0123456789012345678901232
Not Supported:
.---+---+---.
+---+ .-. .-. 0 | | a | | b |
| A | | A | | B | 1 +++ +--++-+-++--+
+---+ '-' '-' 2 | | | | | | |
+---+ .-. .-. 3 +-+ +--++-+-++--+
| C | | C | | D | 4 | | | | | |
+---+ '-' '-' 5 +++ '---+---+---'
0123434567890123456 |
.----. .----.
/ \ / \ .-----+-----+-----.
+ +----+ +----. | | | | .-----+-----+-----+-----+
\ / \ / \ | | | | / / / / /
+----+ B +----+ + +-----+-----+-----+ +-----+-----+-----+-----+
/ \ / \ / | | | | / / / / /
+ A +----+ +----+ | | B | | +-----+-----+-----+-----+
\ / \ / \ +-----+-----+-----+ / / A / B / /
'----+ +----+ + | | | | +-----+-----+-----+-----+
\ / \ / | A | | | / / / / /
'----' '----' '-----+-----+-----' '-----+-----+-----+-----+
+-------------------+ ^ .---.
| A Box |__.--.__ __.--> | .-. | |
| | '--' v | * |<--- | |
+-------------------+ '-' | |
Round *---(-. |
.-----------------. .-------. .----------. .-------. | | |
| Mixed Rounded | | | / Diagonals \ | | | | | |
| & Square Corners | '--. .--' / \ |---+---| '-)-' .--------.
'--+------------+-' .--. | '-------+--------' | | | | / Search /
| | | | '---. | '-------' | '-+------'
|<---------->| | | | v Interior | ^
' <---' '----' .-----------. ---. .--- v |
.------------------. Diag line | .-------. +---. \ / . |
| if (a > b) +---. .--->| | | | | Curved line \ / / \ |
| obj->fcn() | \ / | '-------' |<--' + / \ |
'------------------' '--' '--+--------' .--. .--. | .-. +Done?+-'
.---+-----. | ^ |\ | | /| .--+ | | \ /
| | | Join \|/ | | Curved | \| |/ | | \ | \ /
| | +----> o --o-- '-' Vertical '--' '--' '-- '--' + .---.
<--+---+-----' | /|\ | | 3 |
v not:line 'quotes' .-' '---'
.-. .---+--------. / A || B *bold* | ^
| | | Not a dot | <---+---<-- A dash--is not a line v |
'-' '---------+--' / Nor/is this. ---
More examples are here
The core engine of goat is accessible as a Go library package, for inclusion in specialized
code of your own.
The code implements a subset, and some extensions, of the ASCII diagram generation function of the browser-side Javascript in Markdeep.
A nicely formatted reference may be found at pkg.go.dev.
$ go get -u github.com/blampe/goat/
The diagram above was derived by ./pre-push.sh from ASCII-art in the Go source file ./goat.go.
- Utility and ease of integration into existing projects are paramount.
- Compatibility with MarkDeep desired, but not required.
- TXT and SVG intelligibility are co-equal in priority.
- Composability of TXT not to be sacrificed -- only width-8 characters allowed.
- Per-platform support limited to a single widely-available fixed-pitch TXT font.
