2020-10-21 06:00:42 +00:00
# Notcurses: blingful TUIs and character graphics
2019-12-13 22:14:15 +00:00
2020-07-01 23:31:23 +00:00
* **What it is**: a library facilitating complex TUIs on modern terminal
2020-07-01 23:33:47 +00:00
emulators, supporting vivid colors, multimedia, and Unicode to the maximum
2020-12-03 06:58:15 +00:00
degree possible. [Things ](https://www.youtube.com/watch?v=cYhZ7myXyyg ) can
2020-08-11 23:45:00 +00:00
be done with Notcurses that simply can't be done with NCURSES.
2020-07-01 23:31:23 +00:00
* **What it is not**: a source-compatible X/Open Curses implementation, nor a
replacement for NCURSES on existing systems.
2020-10-15 10:58:33 +00:00
birthed screaming into this world by [nick black ](https://nick-black.com/dankwiki/index.php/Hack_on ) (< nickblack @ linux . com > ).
2020-10-15 11:01:36 +00:00
C++ wrappers by [marek habersack ](http://twistedcode.net/blog/ ) (< grendel @ twistedcode . net > ). the Notcurses API
is stable as of version 2.0.
2019-11-17 10:04:41 +00:00
2020-01-22 11:51:25 +00:00
for more information, see [dankwiki ](https://nick-black.com/dankwiki/index.php/Notcurses )
2020-07-01 23:31:23 +00:00
and the [man pages ](https://notcurses.com/notcurses ). there's also a reference
[in this repo ](USAGE.md ). in addition, there is
[Doxygen ](https://nick-black.com/notcurses/html/ ) output. there is a
[mailing list ](https://groups.google.com/forum/#!forum/notcurses ) which can be reached
2020-10-15 10:57:41 +00:00
via notcurses@googlegroups.com. i wrote a coherent
[guidebook ](https://nick-black.com/htp-notcurses.pdf ), which is available for
free download, or [paperback purchase ](https://amazon.com/dp/B086PNVNC9 ).
2019-12-22 04:31:57 +00:00
2020-10-15 10:58:33 +00:00
i've not yet added many documented examples, but there are many small
2020-10-15 10:57:41 +00:00
C/C++ programs available in [src/poc/ ](https://github.com/dankamongmen/notcurses/tree/master/src/poc ).
2020-11-18 11:29:10 +00:00
`notcurses-demo` covers most of the functionality of Notcurses, and can be
found in [src/demo/ ](https://github.com/dankamongmen/notcurses/tree/master/src/demo ).
2020-04-02 18:01:57 +00:00
2020-06-16 08:13:49 +00:00
**If you're running Notcurses applications in a Docker, please consult
2020-10-17 02:04:47 +00:00
"[Environment notes](#environment-notes)" below.** I track some
[capabilities of terminal emulators ](TERMS.md ), and also maintain a list of
[other TUI libraries ](OTHERS.md ).
2020-02-03 20:26:29 +00:00
2020-10-28 19:26:06 +00:00
![Linux ](https://img.shields.io/badge/-Linux-grey?logo=linux )
2020-10-28 19:27:56 +00:00
![FreeBSD ](https://img.shields.io/badge/-FreeBSD-grey?logo=freebsd )
[![Build ](https://drone.dsscaw.com:4443/api/badges/dankamongmen/notcurses/status.svg )](https://drone.dsscaw.com:4443/dankamongmen/notcurses)
2020-10-28 19:43:16 +00:00
[![pypi_version ](https://img.shields.io/pypi/v/notcurses?label=pypi )](https://pypi.org/project/notcurses)
2020-11-22 06:17:14 +00:00
[![crates.io ](https://img.shields.io/crates/v/libnotcurses-sys.svg )](https://crates.io/crates/libnotcurses-sys)
2020-10-28 19:30:35 +00:00
[![Sponsor ](https://img.shields.io/badge/-Sponsor-red?logo=github )](https://github.com/sponsors/dankamongmen)
2020-07-09 08:15:31 +00:00
2020-07-09 08:04:10 +00:00
< a href = "https://repology.org/project/notcurses/versions" >
< img src = "https://repology.org/badge/vertical-allrepos/notcurses.svg" alt = "Packaging status" align = "right" >
< / a >
2019-11-25 05:26:35 +00:00
* [Introduction ](#introduction )
2019-11-29 03:32:49 +00:00
* [Requirements ](#requirements )
2019-12-24 00:16:57 +00:00
* [Building ](#building )
2019-11-29 06:58:45 +00:00
* [Included tools ](#included-tools )
2019-11-25 05:26:35 +00:00
* [Differences from NCURSES ](#differences-from-ncurses )
2019-11-29 03:32:49 +00:00
* [Features missing relative to NCURSES ](#features-missing-relative-to-ncurses )
2019-12-06 23:33:20 +00:00
* [Adapting NCURSES programs ](#adapting-ncurses-programs )
2019-12-16 07:00:33 +00:00
* [Environment notes ](#environment-notes )
2020-03-13 09:07:33 +00:00
* [TrueColor detection ](#TrueColor-detection )
2019-12-16 07:00:33 +00:00
* [Fonts ](#fonts )
2020-01-05 23:36:33 +00:00
* [FAQs ](#faqs )
2019-12-13 18:00:29 +00:00
* [Supplemental material ](#supplemental-material )
* [Useful links ](#useful-links )
* [History ](#history )
* [Thanks ](#thanks )
2019-11-25 05:26:35 +00:00
## Introduction
2020-04-21 05:50:53 +00:00
Notcurses abandons the X/Open Curses API bundled as part of the Single UNIX
2019-11-19 11:53:50 +00:00
Specification. The latter shows its age, and seems not capable of making use of
2020-03-13 09:07:33 +00:00
terminal functionality such as unindexed 24-bit color ("TrueColor", not to be
confused with the 8-bit indexed 24-bit "extended color" of NCURSES).
For some necessary background, consult Thomas E. Dickey's
2020-01-05 23:36:33 +00:00
superb and authoritative [NCURSES FAQ ](https://invisible-island.net/ncurses/ncurses.faq.html#xterm_16MegaColors ).
2020-12-30 06:06:51 +00:00
As such, Notcurses is not a drop-in Curses replacement.
2019-11-21 16:00:40 +00:00
2020-12-30 06:06:51 +00:00
Wherever possible, Notcurses makes use of the Terminfo library shipped with
2019-11-23 14:07:35 +00:00
NCURSES, benefiting greatly from its portability and thoroughness.
2019-11-18 04:09:06 +00:00
2020-04-21 05:50:53 +00:00
Notcurses opens up advanced functionality for the interactive user on
2019-11-18 04:09:06 +00:00
workstations, phones, laptops, and tablets, at the expense of e.g.
2020-04-18 01:08:22 +00:00
some industrial and retail terminals.
2019-11-18 04:09:06 +00:00
Why use this non-standard library?
2019-12-14 10:33:34 +00:00
* Thread safety, and efficient use in parallel programs, has been a design
consideration from the beginning.
2019-11-18 04:09:06 +00:00
2019-12-14 22:34:10 +00:00
* A svelter design than that codified by X/Open:
2019-12-14 10:33:34 +00:00
* Exported identifiers are prefixed to avoid common namespace collisions.
* The library object exports a minimal set of symbols. Where reasonable,
`static inline` header-only code is used. This facilitates compiler
optimizations, and reduces loader time.
2019-11-18 04:09:06 +00:00
2020-04-18 01:08:22 +00:00
* All APIs natively support the Universal Character Set (Unicode). The `cell`
2020-04-26 21:32:08 +00:00
API is based around Unicode's [Extended Grapheme Cluster ](https://unicode.org/reports/tr29/ ) concept.
2019-12-14 10:33:34 +00:00
* Visual features including images, fonts, video, high-contrast text, sprites,
and transparent regions. All APIs natively support 24-bit color, quantized
down as necessary for the terminal.
2019-11-18 17:16:26 +00:00
2019-11-23 14:05:32 +00:00
* It's Apache2-licensed in its entirety, as opposed to the
2019-11-23 14:12:00 +00:00
[drama in several acts ](https://invisible-island.net/ncurses/ncurses-license.html )
2019-11-23 14:05:32 +00:00
that is the NCURSES license (the latter is [summarized ](https://invisible-island.net/ncurses/ncurses-license.html#issues_freer )
as "a restatement of MIT-X11").
2019-12-14 10:33:34 +00:00
Much of the above can be had with NCURSES, but they're not what NCURSES was
*designed* for. The most fundamental advantage in my mind, though, is
2020-04-21 05:50:53 +00:00
that Notcurses is of the multithreaded era. On the other hand, if you're
2019-12-14 11:40:01 +00:00
targeting industrial or critical applications, or wish to benefit from the
time-tested reliability and portability of Curses, you should by all means use
that fine library.
2019-11-21 14:06:36 +00:00
2019-11-25 03:24:41 +00:00
## Requirements
2020-02-18 17:36:16 +00:00
* (build) A C11 and a C++17 compiler
2020-08-14 03:38:10 +00:00
* (build) CMake 3.14.0+
2020-12-03 06:39:09 +00:00
* (build+runtime) From [NCURSES ](https://invisible-island.net/ncurses/announce.html ): terminfo 6.1+
* (build+runtime) GNU [libunistring ](https://www.gnu.org/software/libunistring/ ) 0.9.10+
2020-04-21 03:26:41 +00:00
* (OPTIONAL) (build+runtime) From QR-Code-generator: [libqrcodegen ](https://github.com/nayuki/QR-Code-generator ) 1.5.0+
2020-05-20 17:22:43 +00:00
* (OPTIONAL) (build+runtime) From [FFmpeg ](https://www.ffmpeg.org/ ): libswscale 5.0+, libavformat 57.0+, libavutil 56.0+
2020-05-13 11:41:19 +00:00
* (OPTIONAL) (build+runtime) [OpenImageIO ](https://github.com/OpenImageIO/oiio ) 2.15.0+
2020-02-19 01:03:20 +00:00
* (OPTIONAL) (testing) [Doctest ](https://github.com/onqtam/doctest ) 2.3.5+
2020-02-18 17:36:16 +00:00
* (OPTIONAL) (documentation) [pandoc ](https://pandoc.org/index.html ) 1.19.2+
2020-07-29 13:34:46 +00:00
* (OPTIONAL) (python bindings): Python 3.7+, [CFFI ](https://pypi.org/project/cffi/ ) 1.13.2+, [pypandoc ](https://pypi.org/project/pypandoc/ ) 1.5+
2020-12-23 19:17:10 +00:00
* (OPTIONAL) (rust bindings): rust 1.47.0+, [bindgen ](https://crates.io/crates/bindgen ) 0.55.1+, pkg-config 0.3.18+, cty 0.2.1+
2020-07-13 12:30:32 +00:00
* (runtime) Linux 5.3+ or FreeBSD 11+
2019-11-25 03:24:41 +00:00
2019-12-24 00:16:57 +00:00
### Building
* Create a subdirectory, traditionally `build` . Enter the directory.
* `cmake ..` . You might want to set e.g. `CMAKE_BUILD_TYPE` .
* `make`
* `make test`
2020-07-13 12:30:32 +00:00
* `make install`
2019-12-24 00:16:57 +00:00
2020-04-24 07:48:56 +00:00
The default multimedia engine is FFmpeg. You can select a different engine
using `USE_MULTIMEDIA` . Valid values are `ffmpeg` , `oiio` (for OpenImageIO),
2020-05-20 17:22:43 +00:00
or `none` . Without a multimedia engine, Notcurses will be unable to decode
images and videos.
2020-04-24 07:48:56 +00:00
2020-05-20 17:22:43 +00:00
Run unit tests with `make test` following a successful build. If you have unit
2020-05-29 06:47:29 +00:00
test failures, *please* file a bug including the output of
`./notcurses-tester -p ../data`
(`make test` also runs `notcurses-tester` , but hides important output).
2020-12-03 06:47:40 +00:00
To watch the bitchin' demo, run `make demo` . More details can
2019-12-24 00:16:57 +00:00
be found on the `notcurses-demo(1)` man page.
2020-10-21 06:10:56 +00:00
Install with `make install` following a successful build. This installs the C
core library, the C headers, the C++ library, and the C++ headers (note that
the C headers are C++-safe). It does not install the Python or Rust wrappers.
To install the Python wrappers (after installing the core library), run:
```
2020-12-01 08:30:23 +00:00
cd cffi
2020-10-21 06:10:56 +00:00
python setup.py build
python setup.py install
```
The Python wrappers are also available from [PyPi ](https://pypi.org/project/notcurses/ ). To install the low-level Rust
wrappers (`libnotcurses-sys`), run:
```
cd rust
cargo build
cargo install
```
The Rust wrappers are also available from [crates.io ](https://crates.io/crates/libnotcurses-sys/ ).
2020-07-13 12:30:32 +00:00
2020-05-20 17:22:43 +00:00
#### Build options
To set the C compiler, export `CC` . To set the C++ compiler, export `CXX` . The
`CMAKE_BUILD_TYPE` CMake variable can be defined to any of its standard values,
but must be `Debug` for use of `USE_COVERAGE` .
* `DFSG_BUILD` : leave out all content considered non-free under the Debian Free
2020-07-21 00:59:49 +00:00
Software Guidelines
* `BUILD_TESTING` : build test targets
2020-08-29 22:55:21 +00:00
* `USE_COVERAGE` : build coverage support (for developers, requires use of Clang)
2020-07-21 00:59:49 +00:00
* `USE_DOCTEST` : build `notcurses-tester` with Doctest, requires `BUILD_TESTING`
2020-08-29 22:55:21 +00:00
* `USE_DOXYGEN` : build interlinked HTML documentation with Doxygen
2020-07-21 00:59:49 +00:00
* `USE_MULTIMEDIA` : `ffmpeg` for FFmpeg, `oiio` for OpenImageIO, `none` for none
2020-05-20 17:22:43 +00:00
* `USE_PANDOC` : build man pages with pandoc
2020-08-29 22:55:21 +00:00
* `USE_POC` : build small, uninstalled proof-of-concept binaries
* `USE_QRCODEGEN` : build qrcode support via libqrcodegen
2020-05-22 03:51:10 +00:00
* `USE_STATIC` : build static libraries (in addition to shared ones)
2020-05-20 17:22:43 +00:00
2019-11-29 06:58:45 +00:00
## Included tools
2020-12-01 08:30:23 +00:00
Seven binaries are installed as part of notcurses:
2019-11-29 06:58:45 +00:00
* `notcurses-demo` : some demonstration code
* `notcurses-view` : renders visual media (images/videos)
* `notcurses-input` : decode and print keypresses
2019-12-14 00:22:11 +00:00
* `notcurses-tester` : unit testing
2020-03-25 08:06:38 +00:00
* `notcurses-tetris` : a tetris clone
2020-06-16 07:11:00 +00:00
* `ncneofetch` : a [neofetch ](https://github.com/dylanaraps/neofetch ) ripoff
2020-12-01 08:30:23 +00:00
* `ncls` : an `ls` that displays multimedia in the terminal
2019-11-29 06:58:45 +00:00
2019-12-21 21:02:27 +00:00
To run `notcurses-demo` from a checkout, provide the `tests/` directory via
the `-p` argument. Demos requiring data files will otherwise abort. The base
delay used in `notcurses-demo` can be changed with `-d` , accepting a
floating-point multiplier. Values less than 1 will speed up the demo, while
values greater than 1 will slow it down.
`notcurses-tester` expects `../tests/` to exist, and be populated with the
necessary data files. It can be run by itself, or via `make test` .
2019-11-23 14:05:32 +00:00
## Differences from NCURSES
2020-10-12 13:44:03 +00:00
The biggest difference, of course, is that Notcurses is not an implementation
2019-11-23 14:05:32 +00:00
of X/Open (aka XSI) Curses, nor part of SUS4-2018.
2020-10-12 13:44:03 +00:00
The detailed differences between Notcurses and NCURSES probably can't be fully
2020-01-24 05:33:28 +00:00
enumerated, and if they could, no one would want to read them. With that said,
2019-11-23 14:05:32 +00:00
some design decisions might surprise NCURSES programmers:
* There is no distinct `PANEL` type. The z-buffer is a fundamental property,
and all drawable surfaces are ordered along the z axis. There is no
equivalent to `update_panels()` .
* Scrolling is disabled by default, and cannot be globally enabled.
2019-11-23 21:03:38 +00:00
* The Curses `cchar_t` has a fixed-size array of `wchar_t` . The notcurses
`cell` instead supports a UTF-8 encoded extended grapheme cluster of
2020-08-14 20:30:54 +00:00
arbitrary length. The only supported encodings are ASCII via `ANSI_X3.4-1968`
and Unicode via `UTF-8` .
* The cursor is disabled by default, when supported (`civis` capability).
2019-11-23 14:05:32 +00:00
* Echoing of input is disabled by default, and `cbreak` mode is used by default.
2020-10-21 06:12:34 +00:00
* Colors are usually specified as 24 bits in 3 components (RGB). If necessary,
these will be quantized for the actual terminal. There are no "color pairs",
but indexed palettes are supported.
2019-11-23 14:05:32 +00:00
* There is no distinct "pad" concept (these are NCURSES `WINDOW` s created with
the `newpad()` function). All drawable surfaces can exceed the display size.
* Multiple threads can freely call into notcurses, so long as they're not
accessing the same data. In particular, it is always safe to concurrently
2019-12-14 12:23:49 +00:00
mutate different `ncplane` s in different threads.
2019-11-23 14:05:32 +00:00
* NCURSES has thread-ignorant and thread-semi-safe versions, trace-enabled and
traceless versions, and versions with and without support for wide characters.
2020-10-12 13:44:03 +00:00
Notcurses is one library: no tracing, UTF-8, thread safety.
* There is no `ESCDELAY` concept; Notcurses expects that all bytes of a
2019-12-13 18:00:29 +00:00
keyboard escape sequence arrive at the same time. This improves latency
2019-12-05 05:26:33 +00:00
and simplifies the API.
2019-12-14 00:22:11 +00:00
* It is an error in NCURSES to print to the bottommost, rightmost coordinate of
the screen when scrolling is disabled (because the cursor cannot be advanced).
2020-10-12 13:44:03 +00:00
Failure to advance the cursor does not result in an error in Notcurses (but
2019-12-14 00:22:11 +00:00
attempting to print at the cursor when it has been advanced off the plane
*does* ).
2019-11-23 14:05:32 +00:00
### Features missing relative to NCURSES
This isn't "features currently missing", but rather "features I do not intend
to implement".
* There is no support for soft labels (`slk_init()`, etc.).
* There is no concept of subwindows which share memory with their parents.
* There is no tracing functionality ala `trace(3NCURSES)` . Superior external
tracing solutions exist, such as `bpftrace` .
2019-11-29 03:08:26 +00:00
2019-12-06 23:33:20 +00:00
### Adapting NCURSES programs
2019-12-14 12:23:49 +00:00
Do you really want to do such a thing? NCURSES and the Curses API it implements
2020-10-12 13:44:03 +00:00
are far more portable and better-tested than Notcurses is ever likely to be.
2019-12-14 12:23:49 +00:00
Will your program really benefit from notcurses's advanced features? If not,
it's probably best left as it is.
2019-12-06 23:33:20 +00:00
Otherwise, most NCURSES concepts have clear partners in notcurses. Any functions
making implicit use of `stdscr` ought be replaced with their explicit
equivalents. `stdscr` ought then be replaced with the result of
`notcurses_stdplane()` (the standard plane). `PANEL` s become `ncplane` s; the
Panels API is otherwise pretty close. Anything writing a bare character will
become a simple `cell` ; multibyte or wide characters become complex `cell` s.
2019-12-14 12:23:49 +00:00
Color no longer uses "color pairs". You can easily enough hack together a
simple table mapping your colors to RGB values, and color pairs to foreground
and background indices into said table. That'll work for the duration of a
porting effort, certainly.
2019-12-06 23:33:20 +00:00
2019-12-14 12:23:49 +00:00
I have adapted two large (~5k lines of C UI code each) programs from NCURSES to
2020-12-03 06:57:23 +00:00
Notcurses, and found it a fairly painless process. It was helpful to introduce
2019-12-07 03:45:08 +00:00
a shim layer, e.g. `compat_mvwprintw` for NCURSES's `mvwprintw` :
```c
static int
compat_mvwprintw(struct ncplane* nc, int y, int x, const char* fmt, ...){
va_list va;
va_start(va, fmt);
2020-01-09 06:48:42 +00:00
if(ncplane_vprintf_yx(nc, y, x, fmt, va) < 0 ) {
2019-12-07 03:45:08 +00:00
va_end(va);
return ERR;
}
va_end(va);
return OK;
}
```
2019-12-06 23:33:20 +00:00
2019-12-14 12:23:49 +00:00
These are pretty obvious, implementation-wise.
2019-11-29 10:54:50 +00:00
## Environment notes
2020-06-16 08:13:49 +00:00
* If your `TERM` variable is wrong, or that terminfo definition is out-of-date,
you're going to have a very bad time. Use *only* the `TERM` values
appropriate for your terminal.
* Ensure your `LANG` environment variable is set to a UTF8-encoded locale, and
that this locale has been generated. This usually means
`"[language]_[Countrycode].UTF-8"` , i.e. `en_US.UTF-8` . The first part
(`en_US`) ought exist as a directory or symlink in `/usr/share/locales` .
This usually requires editing `/etc/locale.gen` and running `locale-gen` .
2020-11-25 04:19:08 +00:00
On Debian systems, this can be accomplished with `dpkg-reconfigure locales` ,
2020-06-16 08:13:49 +00:00
and enabling the desired locale. The default locale is stored somewhere like
`/etc/default/locale` .
2019-11-29 10:54:50 +00:00
* If your terminal has an option about default interpretation of "ambiguous-width
characters" (this is actually a technical term from Unicode), ensure it is
2019-12-18 10:31:29 +00:00
set to **Wide** , not narrow. If that doesn't work, ensure it is set to
**Narrow** , heh.
2019-11-29 10:54:50 +00:00
* If you can disable BiDi in your terminal, do so while running notcurses
2020-10-12 13:44:03 +00:00
applications, until I have that handled better. Notcurses doesn't recognize
2019-11-29 10:54:50 +00:00
the BiDi state machine transitions, and thus merrily continues writing
2019-12-18 10:31:29 +00:00
left-to-right. Likewise, ultra-wide glyphs will have interesting effects.
﷽!
2019-11-29 10:54:50 +00:00
2019-12-24 05:47:31 +00:00
* The unit tests assume dimensions of at least 80x24. They might work in a
2019-12-14 10:33:34 +00:00
smaller terminal. They might not. Don't file bugs on it.
2020-03-13 09:07:33 +00:00
### TrueColor detection
2019-12-16 21:53:11 +00:00
2020-12-03 06:57:23 +00:00
Notcurses primarily loads control sequences from `terminfo(5)` , using the
database entry specified by the `TERM` environment variable. 24-bit "TrueColor"
color support (or at least the ability to specify 3 8-bit channels as arguments
to `setaf` and `setbf` ) is indicated by the `rgb` terminfo capability. Many
terminals with RGB support do not advertise the `rgb` capability. If you
believe your terminal to support 24-bit TrueColor, this can be indicated by
exporting the `COLORTERM` environment variable as `truecolor` or `24bit` .
Note that some terminals accept a 24-bit specification, but map it down to
fewer colors.
2019-12-16 21:53:11 +00:00
2019-12-16 07:00:33 +00:00
### Fonts
2019-12-18 10:31:29 +00:00
Fonts end up being a whole thing, little of which is pleasant. I'll write this
up someday **FIXME** .
2019-12-18 10:02:02 +00:00
2020-12-03 06:57:23 +00:00
It is worth knowing that several terminals draw the block characters directly,
rather than loading them from a font.
2020-01-05 23:36:33 +00:00
### FAQs
2019-12-18 10:02:02 +00:00
2020-06-25 05:27:14 +00:00
If things break or seem otherwise lackluster, **please** consult the
[Environment Notes ](#environment_notes ) section! You **need** to have a correct
`TERM` and `LANG` definition, and probably want `COLORTERM` .
2020-10-17 01:54:07 +00:00
* **Q:** The demo fails in the middle of `intro` . **A:** Check that your `TERM`
2020-10-17 01:47:43 +00:00
value is correct for your terminal. `intro` does a palette fade, which is prone
to breaking under incorrect `TERM` values. If you're not using `xterm` , your
`TERM` should not be `xterm` !
2020-06-25 05:27:14 +00:00
2020-10-17 01:54:07 +00:00
* **Q:** In `xterm` , Alt doesn't work as expected. **A:** Check out the `eightBitInput` resource of `xterm` . Add `XTerm*eightBitInput: false` to your `$HOME/.Xresources` , and run `xrdb -a $HOME/.Xresources` .
2020-06-29 02:31:17 +00:00
2020-10-17 01:54:07 +00:00
* **Q:** Notcurses looks like absolute crap in `screen` . **A:** `screen` doesn't support RGB colors (at least as of 4.08.00); if you have `COLORTERM` defined, you'll have a bad time. If you have a `screen` that was compiled with `--enable-colors256` , try exporting `TERM=screen-256color` as opposed to `TERM=screen` .
2020-07-05 15:24:44 +00:00
2020-10-23 10:59:56 +00:00
* **Q:** Notcurses looks like absolute crap in `mosh` . **A** : Yeah it sure does. I'm not yet sure what's up.
2020-10-17 01:54:07 +00:00
* **Q:** Why didn't you just use Sixel? **A:** Many terminal emulators don't support Sixel. Sixel doesn't work well with mouse selection. With that said, I do intend to support Sixel soon, as a backend, when available, for certain types of drawing (see [issue #200 ](https://github.com/dankamongmen/notcurses/issues/200 )).
2020-01-05 23:36:33 +00:00
2020-10-17 01:54:07 +00:00
* **Q:** I'm not seeing `NCKEY_RESIZE` until I press some other key. **A:** You've almost certainly failed to mask `SIGWINCH` in some thread, and that thread is receiving the signal instead of the thread which called `notcurses_getc_blocking()` . As a result, the `poll()` is not interrupted. Call `pthread_sigmask()` before spawning any threads.
2019-12-16 07:00:33 +00:00
2020-10-17 01:54:07 +00:00
* **Q:** One of the demos claimed to spend more than 100% of its runtime rendering. Do you know how to count? **A:** Runtime is wall clock time. A multithreaded demo can spend more than the wall-clock time rendering if multiple threads run concurrently.
2020-01-18 21:06:57 +00:00
2020-10-17 01:54:07 +00:00
* **Q:** Using the C++ wrapper, how can I ensure that the `NotCurses` destructor is run when I return from `main()` ? **A:** As noted in the [C++ FAQ ](https://isocpp.org/wiki/faq/dtors#artificial-block-to-control-lifetimes ), wrap it in an artificial scope (this assumes your `NotCurses` is scoped to `main()` ).
2020-01-25 16:06:08 +00:00
2020-12-20 23:53:08 +00:00
* **Q:** How do I hide a plane I want to make visible later? **A:** In order of least to most performant: move it offscreen using `ncplane_move_yx()` , move it underneath an opaque plane with `ncplane_move_below()` , or move it off-pile with `ncplane_reparent()` .
2020-01-27 03:24:56 +00:00
2020-10-17 01:54:07 +00:00
* **Q:** Why isn't there an `ncplane_box_yx()` ? Do you hate orthogonality, you dullard? **A:** `ncplane_box()` and friends already have far too many arguments, you monster.
2020-02-12 17:29:28 +00:00
2020-10-17 01:54:07 +00:00
* **Q:** Why doesn't Notcurses support 10- or 16-bit color? **A:** Notcurses supports 24 bits of color, spread across three eight-bit channels. You presumably mean 10-bit-per-channel color. Notcurses will support it when a terminal supports it.
2020-05-04 05:09:17 +00:00
2020-10-17 01:55:22 +00:00
* **Q:** The name is dumb. **A:** That's not a question?
2020-03-26 03:10:31 +00:00
2020-10-17 01:54:07 +00:00
* **Q:** I'm not finding qrcodegen on FreeBSD, despite having installed `graphics/qr-code-generator` . **A:** Try `cmake -DCMAKE_REQUIRED_INCLUDES=/usr/local/include` . This is passed by `bsd.port.mk` .
2020-05-22 09:32:47 +00:00
2020-10-17 01:54:07 +00:00
* **Q:** Do you support [musl ](https://musl.libc.org/ )? **A:** I try to! You'll need at least 1.20.
2020-06-25 05:13:40 +00:00
2020-10-17 01:56:29 +00:00
* **Q:** I only seem to blit in ASCII, and/or can't emit Unicode beyond ASCII in general. **A:** Your `LANG` environment variable is underdefined or incorrectly defined, or the necessary locale is not present on your machine (it is also possible that you explicitly supplied `NCOPTION_INHIBIT_SETLOCALE` , but never called `setlocale(3)` , in which case don't do that).
2020-08-14 09:23:36 +00:00
2020-10-17 01:57:18 +00:00
* **Q:** I pretty much always need an `ncplane` when using a `cell` . Why doesn't the latter hold a pointer to the former? **A:** Besides the massive redundancy this would entail, `cell` needs to remain as small as possible, and you almost always have the `ncplane` handy if you've got a reference to a valid `cell` anyway.
2020-08-14 09:23:36 +00:00
2020-10-21 06:03:55 +00:00
* **Q:** I ran `notcurses-demo` with a single demo, but my summary numbers don't match that demo's numbers, you charlatan. **A:** `notcurses-demo` renders several frames beyond the actual demos.
2020-08-20 20:19:21 +00:00
2020-10-21 06:03:55 +00:00
* **Q:** When my program exits, I don't have a cursor, or text is invisible, or colors are weird, < i > ad nauseam</ i > . **A:** Ensure you're calling `notcurses_stop()` /`ncdirect_stop()` on all exit paths, including fatal signals.
2020-10-11 01:09:50 +00:00
2020-10-21 06:03:55 +00:00
* **Q:** How can I use Direct Mode in conjunction with libreadline? **A:** Pass `NCDIRECT_OPTION_CBREAK` to `ncdirect_init()` , call `ncdirect_init()` prior to calling `rl_prep_terminal()` , and call `rl_deprep_terminal()` before calling `ncdirect_stop()` . But you should probably just use a Notcurses `ncreader` , if possible.
2020-10-17 01:44:10 +00:00
2020-10-21 06:03:55 +00:00
* **Q:** Will there ever be Java wrappers? **A:** I should hope not.
2020-10-11 01:09:50 +00:00
2020-10-29 16:30:39 +00:00
* **Q:** Given that the glyph channel is initialized as transparent for a plane, shouldn't the foreground and background be initialized as transparent, also? **A:** Probably (they are instead initialized to default opaque). This would change some of the most longstanding behavior of Notcurses, though, so it isn't happening.
2019-12-13 18:00:29 +00:00
## Supplemental material
### Useful links
2019-11-29 03:08:26 +00:00
* [BiDi in Terminal Emulators ](https://terminal-wg.pages.freedesktop.org/bidi/ )
* [The Xterm FAQ ](https://invisible-island.net/xterm/xterm.faq.html )
2019-12-23 03:45:20 +00:00
* [XTerm Control Sequences ](https://invisible-island.net/xterm/ctlseqs/ctlseqs.pdf )
2019-11-29 03:08:26 +00:00
* [The NCURSES FAQ ](https://invisible-island.net/ncurses/ncurses.faq.html )
* [ECMA-35 Character Code Structure and Extension Techniques ](https://www.ecma-international.org/publications/standards/Ecma-035.htm ) (ISO/IEC 2022)
* [ECMA-43 8-bit Coded Character Set Structure and Rules ](https://www.ecma-international.org/publications/standards/Ecma-043.htm )
* [ECMA-48 Control Functions for Coded Character Sets ](https://www.ecma-international.org/publications/standards/Ecma-048.htm ) (ISO/IEC 6429)
* [Unicode 12.1 Full Emoji List ](https://unicode.org/emoji/charts/full-emoji-list.html )
2019-12-02 15:39:48 +00:00
* [Unicode Standard Annex #29 Text Segmentation ](http://www.unicode.org/reports/tr29 )
2019-11-29 03:08:26 +00:00
* [Unicode Standard Annex #15 Normalization Forms ](https://unicode.org/reports/tr15/ )
2019-11-29 09:57:09 +00:00
* [The TTY demystified ](http://www.linusakesson.net/programming/tty/ )
2019-12-14 10:33:34 +00:00
* [Dark Corners of Unicode ](https://eev.ee/blog/2015/09/12/dark-corners-of-unicode/ )
* [UTF-8 Decoder Capability and Stress Test ](https://www.cl.cam.ac.uk/~mgk25/ucs/examples/UTF-8-test.txt )
2020-06-05 08:19:56 +00:00
* [Emoji: how do you get from U+1F355 to 🍕? ](https://meowni.ca/posts/emoji-emoji-emoji/ )
2020-06-16 22:48:51 +00:00
* [Glyph Hell: An introduction to glyphs, as used and defined in the FreeType engine ](http://chanae.walon.org/pub/ttf/ttf_glyphs.htm )
2019-12-13 18:00:29 +00:00
2019-12-23 03:45:20 +00:00
#### Useful man pages
* Linux: [console_codes(4) ](http://man7.org/linux/man-pages/man4/console_codes.4.html )
* Linux: [termios(3) ](http://man7.org/linux/man-pages/man3/termios.3.html )
* Linux: [ioctl_tty(2) ](http://man7.org/linux/man-pages/man2/ioctl_tty.2.html )
* Linux: [ioctl_console(2) ](http://man7.org/linux/man-pages/man2/ioctl_console.2.html )
* Portable: [terminfo(5) ](http://man7.org/linux/man-pages/man5/terminfo.5.html )
2019-12-23 07:47:34 +00:00
* Portable: [user_caps(5) ](http://man7.org/linux/man-pages/man5/user_caps.5.html )
2019-12-23 03:45:20 +00:00
2019-12-13 18:00:29 +00:00
### History
2020-12-13 08:24:20 +00:00
* 2020-12-13: Notcurses [2.1.0 "rubberband man" ](https://github.com/dankamongmen/notcurses/releases/tag/v2.1.0 ).
2020-11-29 00:06:50 +00:00
* 2020-11-23: [Invited presentation ](https://mdco2.mini.debconf.org/talks/6-notcurses-making-terminals-do-things-that-were-never-intended/ ) at [DebMiniConf #2 ](https://mdco2.mini.debconf.org/ ).
2020-10-12 13:44:03 +00:00
* 2020-10-12: Notcurses [2.0.0 "stankonia" ](https://github.com/dankamongmen/notcurses/releases/tag/v2.0.0 ).
2020-11-29 00:08:26 +00:00
* A stable API! This API will be supported going forward. [Hype video ](https://www.youtube.com/watch?v=cYhZ7myXyyg )!
2020-10-01 16:08:22 +00:00
* 2020-08-30: Notcurses [1.7.0 "don't pull the bang out" ](https://github.com/dankamongmen/notcurses/releases/tag/v1.7.0 ).
2020-07-04 03:41:26 +00:00
* 2020-07-04: Notcurses [1.6.0 "aquemini" ](https://github.com/dankamongmen/notcurses/releases/tag/v1.6.0 ).
* 2020-07-03: Notcurses is [accepted into Alpine Edge ](https://gitlab.alpinelinux.org/alpine/aports/-/merge_requests/9924 ).
2020-06-16 08:13:49 +00:00
* 2020-06-08: Notcurses [1.5.0 "ghetto bird" ](https://github.com/dankamongmen/notcurses/releases/tag/v1.5.0 ).
2020-05-13 18:56:09 +00:00
* 2020-05-13: Notcurses is [accepted into Fedora Core ](https://bugzilla.redhat.com/show_bug.cgi?id=1822971 ).
2020-05-11 16:30:53 +00:00
* 2020-05-10: Notcurses [1.4.0 "the saga continues" ](https://github.com/dankamongmen/notcurses/releases/tag/v1.4.0 ).
* 2020-05-09: Notcurses is [accepted into FreeBSD ](https://github.com/dankamongmen/notcurses/issues/575 ).
2020-04-21 05:50:53 +00:00
* 2020-04-19: Notcurses is [accepted into Debian ](https://bugs.debian.org/950492 ).
* 2020-04-12: Notcurses [1.3.0 "hypnotize" ](https://github.com/dankamongmen/notcurses/releases/tag/v1.3.0 ).
* 2020-04-08: The Notcurses book [is published ](https://amazon.com/dp/B086PNVNC9 ).
* 2020-03-23: Notcurses is featured on [Linux World News ](https://lwn.net/Articles/815811/ ).
* 2020-02-17: Notcurses [1.2.0 "check the résumé, my record's impeccable" ](https://github.com/dankamongmen/notcurses/releases/tag/v1.2.0 ).
* 2019-01-19: Notcurses [1.1.0 "all the hustlas they love it just to see one of us make it" ](https://github.com/dankamongmen/notcurses/releases/tag/v1.1.0 ).
2020-01-19 20:04:42 +00:00
Much better video support, pulsing planes, palette256.
2020-05-09 10:08:23 +00:00
* The new [hype video ](https://www.youtube.com/watch?v=-H1WkopWJNMk ) gets a lot of attention.
2020-04-21 05:50:53 +00:00
* 2019-01-04: Notcurses [1.0.0 "track team, crack fiend, dying to geek" ](https://github.com/dankamongmen/notcurses/releases/tag/v1.0.0 )
2020-01-04 13:39:20 +00:00
is released, six days ahead of schedule. 147 issues closed. 702 commits.
2020-04-21 05:50:53 +00:00
* 2019-12-18: Notcurses [0.9.0 "You dig in! You dig out! You get out!" ](https://github.com/dankamongmen/notcurses/releases/tag/v0.9.0 ),
2020-10-12 13:44:03 +00:00
and also the first contributor besides myself (@grendello). Last major pre-GA release.
2020-04-21 05:50:53 +00:00
* 2019-12-05: Notcurses [0.4.0 "TRAP MUSIC ALL NIGHT LONG" ](https://github.com/dankamongmen/notcurses/releases/tag/v0.4.0 ),
2020-05-09 10:08:23 +00:00
the first generally usable notcurses.
* I prepare a [demo ](https://www.youtube.com/watch?v=eEv2YRyiEVM ), and release it on YouTube.
2020-02-05 22:29:42 +00:00
* November 2019: I begin work on [Outcurses ](https://github.com/dankamongmen/ncreels ).
Outcurses is a collection of routines atop NCURSES, including ncreels.
2019-12-13 18:00:29 +00:00
I study the history of NCURSES, primarily using Thomas E. Dickey's FAQ and
the mailing list archives.
2020-02-05 22:29:42 +00:00
* 2019-11-14: I file [Outcurses issue #56 ](https://github.com/dankamongmen/ncreels/issues/56 )
2020-03-13 09:07:33 +00:00
regarding use of TrueColor in outcurses. This is partially inspired by
2019-12-13 18:00:29 +00:00
Lexi Summer Hale's essay [everything you ever wanted to know about terminals ](http://xn--rpa.cc/irl/term.html ).
I get into contact with Thomas E. Dickey and confirm that what I'm hoping
to do doesn't really fit in with the codified Curses API.
* 2019-11-16: I make the [first commit ](https://github.com/dankamongmen/notcurses/commit/635d7039d79e4f94ba645e8cb601e3a6d82a6b30 )
2020-04-21 05:50:53 +00:00
to Notcurses.
2019-12-13 18:00:29 +00:00
* September 2019: I extracted fade routines from Growlight and Omphalos, and
offered them to NCURSES as extensions. They are not accepted, which is
2020-02-05 22:29:42 +00:00
understandable. I mention that I intend to extract ncreels, and offer to
2019-12-13 18:00:29 +00:00
include them in the CDK (Curses Development Kit). [Growlight issue #43 ](https://github.com/dankamongmen/growlight/issues/43 )
is created regarding this extraction. A few minor patches go into NCURSES.
* 2011, 2013: I develop [Growlight ](https://github.com/dankamongmen/growlight )
and [Omphalos ](https://github.com/dankamongmen/omphalos ), complicated TUIs
making extensive use of NCURSES.
### Thanks
* Notcurses could never be what it is without decades of tireless, likely
thankless work by Thomas E. Dickey on NCURSES. His FAQ is a model of
engineering history. He exemplifies documentation excellence and
2019-12-17 02:29:59 +00:00
conservative, thoughtful stewardship. The free software community owes
2019-12-13 18:00:29 +00:00
Mr. Dickey a great debt.
2020-04-21 05:50:53 +00:00
* Robert Edmonds provided tremendous assistance Debianizing the package,
and David Cantrell did likewise for Fedora. Both are hella engineers.
2019-12-13 18:00:29 +00:00
* Justine Tunney, one of my first friends at Google NYC, was always present
with support, and pointed out the useful memstream functionality of
POSIX, eliminating the need for me to cons up something similar.
* I one night read the entirety of Lexi Summer Hale's [essays ](http://xn--rpa.cc/irl/index.html ),
and woke up intending to write notcurses.
2020-01-19 09:39:15 +00:00
* NES art was lifted from [The Spriters Resource ](https://www.spriters-resource.com/nes/ )
and [NES Sprite ](http://nes-sprite.resampled.ru/ ), the kind of sites that
make the Internet great. It probably violates any number of copyrights. C'est la vie.
2020-01-19 07:31:08 +00:00
* Mark Ferrari, master of the pixel, for no good reason allowed me to reproduce
his incredible and groundbreaking color-cycling artwork. Thanks Mark!
2020-06-05 19:14:07 +00:00
* The world map image was made by [Vecteezy ](https://www.vecteezy.com/free-vector/world-map ),
and is used according to the terms of their License.
2019-12-13 18:00:29 +00:00
* Finally, the [demoscene ](https://en.wikipedia.org/wiki/Demoscene ) and general
l33t scene of the 90s and early twenty-first century endlessly inspired a
young hax0r. There is great joy in computing; no one will drive us from
this paradise Turing has created!
> “Our fine arts were developed, their types and uses were established, in times
very different from the present, by men whose power of action upon things was
insignificant in comparison with ours. But the amazing growth of our
techniques, the adaptability and precision they have attained, the ideas and
habits they are creating, make it a certainty that _profound changes are
2019-12-14 23:44:04 +00:00
impending in the ancient craft of the Beautiful_.” —Paul Valéry
2020-12-16 15:58:36 +00:00
### Grotesque vanity and meaningless metrics
[![stargazers over time ](https://starcharts.herokuapp.com/dankamongmen/notcurses.svg )](https://starcharts.herokuapp.com/dankamongmen/notcurses)