diff --git a/doc/foot.ini.5.scd b/doc/foot.ini.5.scd index a8bf572a..fdf22497 100644 --- a/doc/foot.ini.5.scd +++ b/doc/foot.ini.5.scd @@ -44,77 +44,77 @@ commented out will usually be installed to */etc/xdg/foot/foot.ini*. options. Most noteworthy is *:size=n*, which is used to set the font size. Note that the font size is also affected by the *dpi-aware* option. - + Examples: - Dina:weight=bold:slant=italic - Courier New:size=12 - Fantasque Sans Mono:fontfeatures=ss01 - + For each option, the first font is the primary font. The remaining fonts are fallback fonts that will be used whenever a glyph cannot be found in the primary font. - + The fallback fonts are searched in the order they appear. If a glyph cannot be found in any of the fallback fonts, the dynamic fallback list from fontconfig (for the primary font) is searched. - + *font-bold*, *font-italic* and *font-bold-italic* allow custom fonts to be used for bold/italic/bold+italic fonts. If left unconfigured, the bold/italic variants of the regular font(s) specified in *font* are used. *Note*: you _may_ have to tweak the size(s) of the custom bold/italic fonts to match the regular font. - + To disable bold and/or italic fonts, set e.g. *font-bold* to _exactly_ the same value as *font*. - + Default: _monospace:size=8_ (*font*), _not set_ (*font-bold*, *font-italic*, *font-bold-italic*). *include* Absolute path to configuration file to import. - + The import file has its own section scope. I.e. the including configuration is still in the default section after the include, regardless of which section the included file ends in. - + - The path must be an absolute path, or start with *~/*. - Multiple include directives are allowed, but only one path per directive. - Nested imports are allowed. - + Default: _not set_. *line-height* An absolute value, in _points_, that override line height from the font metrics. - + You can specify a height in _pixels_ by using the *px* suffix: e.g. *line-height=12px*. - + See also: *vertical-letter-offset*. - + Default: _not set_. *letter-spacing* Spacing between letters, in _points_. A positive value will increase the cell size, and a negative value shrinks it. - + You can specify a letter spacing in _pixels_ by using the *px* suffix: e.g. *letter-spacing=2px*. - + See also: *horizontal-letter-offset*. - + Default: _0_. *horizontal-letter-offset*, *vertical-letter-offset* Configure the horizontal and vertical offsets used when positioning glyphs within cells, in _points_, relative to the top left corner. - + To specify an offset in _pixels_, append *px*: e.g. *horizontal-letter-offset=2px*. - + Default: _0_. *underline-offset* @@ -122,20 +122,20 @@ commented out will usually be installed to */etc/xdg/foot/foot.ini*. _points_ and relative the font's baseline. A positive value positions the underline under the baseline, while a negative value positions it above the baseline. - + To specify an offset in _pixels_, append *px*: *underline-offset=2px*. - + If left unset (the default), the offset specified in the font is used, or estimated by foot if the font lacks underline positioning information. - + Default: _unset_. *box-drawings-uses-font-glyphs* Boolean. When disabled, foot generates box/line drawing characters itself. The are several advantages to doing this instead of using font glyphs: - + - No antialiasing effects where e.g. line endpoints appear dimmed down, or blurred. - Line- and box characters are guaranteed to span the entire cell, @@ -144,60 +144,60 @@ commented out will usually be installed to */etc/xdg/foot/foot.ini*. - Many fonts lack some, or all, of the line- and box drawing characters, causing fallback fonts to be used, which results in out-of-place looking glyphs (for example, badly sized). - + When enabled, box/line drawing characters are rendered using font glyphs. This may result in a more uniform look, in some use cases. - + Default: _no_. *dpi-aware* *auto*, *yes*, or *no*. - + When set to *yes*, fonts are sized using the monitor's DPI, making a font of a given size have the same physical size, regardless of monitor. In other words, if you drag a foot window between different monitors, the font size remains the same. - + In this mode, the monitor's scaling factor is ignored; doubling the scaling factor will *not* double the font size. - + When set to *no*, the monitor's DPI is ignored. The font is instead sized using the monitor's scaling factor; doubling the scaling factor *does* double the font size. - + Finally, if set to *auto*, fonts will be sized using the monitor's DPI if _all_ monitors have a scaling factor of 1. If at least one monitor as a scaling factor larger than 1 (regardless of whether the foot window is mapped on that monitor or not), fonts will be scaled using the scaling factor. - + Note that this option typically does not work with bitmap fonts, which only contains a pre-defined set of sizes, and cannot be dynamically scaled. Whichever size (of the available ones) that best matches the DPI or scaling factor, will be used. - + Also note that if the font size has been specified in pixels (*:pixelsize=*_N_, instead of *:size=*_N_), DPI scaling (*dpi-aware=yes*) will have no effect (the specified pixel size will be used as is). But, if the monitor's scaling factor is used to size the font (*dpi-aware=no*), the font's pixel size will be multiplied with the scaling factor. - + Default: _auto_ *pad* Padding between border and glyphs, in pixels (subject to output scaling), in the form _XxY_. - + This will add _at least_ X pixels on both the left and right sides, and Y pixels on the top and bottom sides. The grid content will be anchored in the top left corner. I.e. if the window manager forces an odd window size on foot, the additional pixels will be added to the right and bottom sides. - + To instead center the grid content, append *center* (e.g. *pad=5x5 center*). - + Default: _2x2_. *resize-delay-ms* @@ -205,18 +205,18 @@ commented out will usually be installed to */etc/xdg/foot/foot.ini*. window dimensions to the client application while doing an interactive resize of a foot window. Idle time in this context is a period of time where the window size is not changing. - + In other words, while you are fiddling with the window size, foot does not send the updated dimensions to the client. Only when you pause the fiddling for *resize-delay-ms* milliseconds is the client updated. - + Emphasis is on _while_ here; as soon as the interactive resize ends (i.e. when you let go of the window border), the final dimensions is sent to the client, without any delays. - + Setting it to 0 disables the delay completely. - + Default: _100_. *initial-window-size-pixels* @@ -229,12 +229,12 @@ commented out will usually be installed to */etc/xdg/foot/foot.ini*. Initial window width and height in _characters_, in the form _WIDTHxHEIGHT_. Mutually exclusive to *initial-window-size-pixels*.' - + Note that if you have a multi-monitor setup, with different scaling factors, there is a possibility the window size will not be set correctly. If that is the case, use *initial-window-size-pixels* instead. - + Default: _not set_. *initial-window-mode* @@ -257,12 +257,12 @@ commented out will usually be installed to */etc/xdg/foot/foot.ini*. Semi-boolean. When enabled, bold text is rendered in a brighter color (in addition to using a bold font). The color is brightened by increasing its luminance. - + If set to *palette-based*, rather than a simple *yes|true*, colors matching one of the 8 regular palette colors will be brightened using the corresponding bright palette color. Other colors will not be brightened. - + Default: _no_. *word-delimiters* @@ -274,19 +274,19 @@ commented out will usually be installed to */etc/xdg/foot/foot.ini*. Command to execute to display a notification. _${title}_ and _${body}_ will be replaced with the notification's actual _title_ and _body_ (message content). - + _${app-id}_ is replaced with the value of the command line option _--app-id_, and defaults to *foot*. - + _${window-title}_ is replaced with the current window title. - + Applications can trigger notifications in the following ways: - + - OSC 777: *\\e]777;notify;;<body>\\e\\\\* - + By default, notifications are *inhibited* if the foot window has keyboard focus. See _notify-focus-inhibit_. - + Default: _notify-send -a ${app-id} -i ${app-id} ${title} ${body}_. *notify-focus-inhibit* @@ -311,13 +311,13 @@ commented out will usually be installed to */etc/xdg/foot/foot.ini*. When set to _yes_, foot will signal urgency to the compositor through the XDG activation protocol whenever *BEL* is received, and the window does NOT have keyboard foccus. - + If the compositor does not implement this protocol, the margins will be painted in red instead. - + Applications can enable/disable this feature programmatically with the *CSI ? 1042 h* and *CSI ? 1042 l* escape sequences. - + Default: _no_ *notify* @@ -370,24 +370,24 @@ commented out will usually be installed to */etc/xdg/foot/foot.ini*. *osc8-underline* When to underline OSC-8 URLs. Possible values are *url-mode* and *always*. - + When set to *url-mode*, OSC-8 URLs are only highlighted in URL mode, just like auto-detected URLs. - + When set to *always*, OSC-8 URLs are always highlighted, regardless of their other attributes (bold, italic etc). Note that this does _not_ make them clickable. - + Default: _url-mode_ *label-letters* String of characters to use when generating key sequences for URL jump labels. - + If you change this option to include the letter *t*, you should also change the default *[url-bindings].toggle-url-visible* key binding to avoid a clash. - + Default: _sadfjklewcmpgh_. *protocols* @@ -400,7 +400,7 @@ commented out will usually be installed to */etc/xdg/foot/foot.ini*. *uri-characters* Set of characters allowed in auto-detected URLs. Any character not included in this set constitutes a URL delimiter. - + Default: _abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-\_.,~:;/?#@!$&%\*+="'()[]_ @@ -422,7 +422,7 @@ applications can change these at runtime. Two RRGGBB values (i.e. plain old 6-digit hex values, without prefix) specifying the foreground (text) and background (cursor) colors for the cursor. - + Default: _inverse foreground/background colors_. Note that this value only applies to the block cursor. The other @@ -437,13 +437,13 @@ applications can change these at runtime. *underline-thickness* Thickness (height) of the underline styled cursor. The value is in points, and its exact value thus depends on the monitor's DPI. - + To instead specify a thickness in pixels, use the *px* suffix: e.g. *underline-thickness=2px*. - + Note that if left unset, the cursor's thickness will scale with the font size, while if set, the size is fixed. - + Default: _font underline thickness_. # SECTION: mouse @@ -457,17 +457,17 @@ applications can change these at runtime. scroll mode_. When this mode is enabled, mouse scroll events are translated to _up_/_down_ key events when displaying the alternate screen. - + This lets you scroll with the mouse in e.g. pagers (like _less_) without enabling native mouse support in them. - + Alternate scrolling is *not* used if the application enables native mouse support. - + This option can be modified by applications at run-time using the escape sequences *CSI ? 1007 h* (enable) and *CSI ? 1007 l* (disable). - + Default: _yes_. # SECTION: colors @@ -502,30 +502,30 @@ can configure the background transparency with the _alpha_ option. Custom colors to use with dimmed colors. Dimmed colors do not have an entry in the color palette. Applications emit them by combining a color value, and a "dim" attribute. - + By default, foot implements this by reducing the luminance of the current color. This is a generic approach that applies to both colors from the 256-color palette, as well as 24-bit RGB colors. - + You can change this behavior by setting the *dimN* options. When set, foot will match the current color against the color palette, and if it matches one of the *regularN* colors, the corresponding *dimN* color will be used. - + If instead the current color matches one of the *brightN* colors, the corresponding *regularN* color will be used. - + If the current color does not match any known color, it is dimmed by reducing the luminance (i.e. the same behavior as if the *dimN* options are unconfigured). 24-bit RGB colors will typically fall into this category. - + Note that applications can change the *regularN* and *brighN* colors at runtime. However, they have no way of changing the *dimN* colors. If an application has changed the *regularN* colors, foot will still use the corresponding *dimN* color, as configured in foot.ini. - + Default: _not set_. *0* *..* *255* @@ -579,12 +579,12 @@ Examples: *preferred* Which type of window decorations to prefer: *client* (CSD), *server* (SSD) or *none*. - + Note that this is only a hint to the compositor. Depending on compositor support, and how it has been configured, it may instruct foot to use CSDs even though this option has been set to *server*, or render SSDs despite *client* or *none* being set. - + Default: _server_. *size* @@ -742,17 +742,17 @@ e.g. *search-start=none*. currently selected text to an external tool. The syntax for this option is a bit special; the first part of the value is the command to execute enclosed in "[]", followed by the binding(s). - + You can configure multiple pipes as long as the command strings are different and the key bindings are unique. - + Note that the command is *not* automatically run inside a shell; use *sh -c "command line"* if you need that. - + Example: *pipe-visible=[sh -c "xurls | uniq | tac | fuzzel | xargs -r firefox"] Control+Print* - + Default: _not bound_ *show-urls-launch* @@ -863,14 +863,14 @@ Be careful; do not use single-letter keys that are also used in By default, the jump label only shows the key sequence required to activate it. This is fine as long as the URL is visible in the original text. - + But with e.g. OSC-8 URLs (the terminal version of HTML anchors, i.e. "links"), the text on the screen can be something completey different than the URL. - + This action toggles between showing and hiding the URL on the jump label. - + Default: _t_. # SECTION: text-bindings @@ -1002,25 +1002,25 @@ any of these options. *bilinear*, *cubic* or *lanczos3*. *cubic* and *lanczos3* produce the best results, but are slower (with *lanczos3* being the best _and_ slowest). - + Default: _lanczos3_. *overflowing-glyphs* Boolean. When enabled, glyphs wider than their cell(s) are allowed to render into one additional neighbouring cell. - + One use case for this are fonts with wide italic characters that "bend" into the next cell. Without this option, such glyphs will appear "cut off". - + Another use case are fonts with "icon" characters in the Unicode private usage area, e.g. Nerd Fonts, or Powerline Fonts and legacy emoji characters like *WHITE FROWNING FACE*. - + Note: might impact performance depending on the font used. Especially small font sizes can cause many overflowing glyphs because of subpixel rendering. - + Default: _yes_. *render-timer* @@ -1040,17 +1040,17 @@ any of these options. Boolean. When enabled, box drawing "shades" (e.g. LIGHT SHADE, MEDIUM SHADE and DARK SHADE) are rendered as solid blocks using a darker variant of the current foreground color. - + When disabled, they are instead rendered as checker box pattern, using the current foreground color as is. - + Default: _yes_. *delayed-render-lower*, *delayed-render-upper* These two values control the timeouts (in nanoseconds) that are used to mitigate screen flicker caused by clients writing large, non-atomic screen updates. - + If a client splits up a screen update over multiple *write*(3) calls, we may end up rendering an intermediate frame, quickly followed by another frame with the final screen content. For @@ -1059,56 +1059,56 @@ any of these options. writes. Rendering the frame when the screen has been erased, but not yet filled with new content will be perceived as screen flicker. - + The *real* solution to this is _Application Synchronized Updates_ (https://gitlab.freedesktop.org/terminal-wg/specifications/-/merge_requests/2). - + The problem with this is twofold - first, it has not yet been standardized, and thus there are not many terminal emulators that implement it (foot *does* implement it), and second, applications must be patched to use it. - + Until this has happened, foot offers an interim workaround; an attempt to mitigate the screen flicker *without* affecting neither performance nor latency. - + It is based on the fact that the screen is updated at a fixed interval (typically 60Hz). For us, this means it does not matter if we render a new frame at the *beginning* of a frame interval, or at the *end*. Thus, the goal is to introduce a delay between receiving client data and rendering the resulting state, but without causing a frame skip. - + While it should be possible to estimate the amount of time left until the next frame, foot's algorithm is currently not that advanced, but is based on statistics I guess you could say - the delay we introduce is so small that the risk of pushing the frame over to the next frame interval is also very small. - + Now, that was a lot of text. But what is it foot actually does? - + When receiving client data, it schedules a timer, the *delayed-render-lower*. If we do not receive any more client data before the timer has run out, we render the frame. If however, we do receive more data, the timer is re-scheduled. That is, each time we receive client data, frame rendering is delayed another *delayed-render-lower* nanoseconds. - + Now, while this works very well with most clients, it would be possible to construct a malicious client that keeps writing data at a slow pace. To the user, this would look like foot has frozen as we never get to render a new frame. To prevent this, an upper limit is set - *delayed-render-upper*. If this timer runs out, we render the frame regardless of what the client is doing. - + If changing these values, note that the lower timeout *must* be set lower than the upper timeout, but that this is not verified by foot. Furthermore, both values must be less than 16ms (that is, 16000000 nanoseconds). - + You can disable the feature altogether by setting either value to 0. In this case, frames are rendered "as soon as possible". - + Default: lower=_500000_ (0.5ms), upper=_8333333_ (8.3ms - half a frame interval). @@ -1117,14 +1117,14 @@ any of these options. time a frame has been rendered. This forces the compositor to redraw the entire window. If disabled, foot will only 'damage' updated rows. - + There is normally *no* reason to enable this. However, it has been seen to workaround an issue with _fractional scaling_ in _Gnome_. - + Note that enabling this option is likely to increase CPU and/or GPU usage (by the compositor, not by foot), and may have a negative impact on battery life. - + Default: _no_. *grapheme-shaping* @@ -1132,90 +1132,90 @@ any of these options. cluster segmentation while parsing "printed" text. Then, when rendering, it will use _fcft_ (if compiled with _HarfBuzz_ support) to shape the grapheme clusters. - + This is required to render e.g. flag (emoji) sequences, keycap sequences, modifier sequences, zero-width-joiner (ZWJ) sequences and emoji tag sequences. It might also improve rendering of composed characters, depending on font. - + - foot must have been compiled with utf8proc support - fcft must have been compiled with HarfBuzz support - + See also: *grapheme-width-method*. - + Default: _yes_ *grapheme-width-method* Selects which method to use when calculating the width (i.e. number of columns) of a grapheme cluster. One of *wcswidth*, *double-width* and *max*. - + *wcswidth* simply adds together the individual width of all codepoints making up the cluster. - + *double-width* does the same, but limits the maximum number of columns to 2. This is more correct, but may break some applications since applications typically use *wcswidth*(3) internally to calculate the width. This results in cursor de-synchronization issues. - + *max* uses the width of the largest codepoint in the cluster. - + Default: _wcswidth_ *font-monospace-warn* Boolean. When enabled, foot will use heuristics to try to verify the primary font is a monospace font, and warn if it is not. - + Disable this if you still want to use the font, even if foot thinks it is not monospaced. - + You may also want to disable it to get slightly faster startup times. - + Default: _yes_ *max-shm-pool-size-mb* This option controls the amount of virtual address space used by the pixmap memory to which the terminal screen content is rendered. - + It does not change how much physical memory foot uses. - + Foot uses a memory mapping trick to implement fast rendering of interactive scrolling (typically, but applies to "slow" scrolling in general). Example: holding down the 'up' or 'down' arrow key to scroll in a text editor. - + For this to work, it needs a large amount of virtual address space. Again, note that this is not physical memory. - + On a normal x64 based computer, each process has 128TB of virtual address space, and newer ones have 64PB. This is an insane amount and most applications do not use anywhere near that amount. - + Each foot terminal window can allocate up to 2GB of virtual address space. With 128TB of address space, that means a maximum of 65536 windows in server/daemon mode (for 2GB). That should be enough, yes? - + However, the Wayland compositor also needs to allocate the same amount of virtual address space. Thus, it has a slightly higher chance of running out of address space since it needs to host all running Wayland clients in the same way, at the same time. - + In the off chance that this becomes a problem for you, you can reduce the amount used with this option. - + Or, for optimal performance, you can increase it to the maximum allowed value, 2GB (but note that you most likely will not notice any difference compared to the default value). - + Setting it to 0 disables the feature. - + Limitations: - only supported on 64-bit architectures - only supported on Linux - + Default: _512_. Maximum allowed: _2048_ (2GB). *sixel*