add width to guifont settings

src/renderer/fonts/caching_shaper.rs

@@ -176,10 +176,10 @@ impl CachingShaper {
 
     pub fn font_base_dimensions(&mut self) -> (u64, u64) {
         let (metrics, glyph_advance) = self.info();
-        let font_width = (glyph_advance + 0.5).floor() as u64;
 
         let bare_font_height = (metrics.ascent + metrics.descent + metrics.leading).ceil();
         let font_height = bare_font_height as i64 + self.linespace;
+        let font_width = (glyph_advance + self.options.width + 0.5).floor() as u64;
 
         (
             font_width,

src/renderer/fonts/font_options.rs

@@ -6,6 +6,7 @@ const DEFAULT_FONT_SIZE: f32 = 14.0;
 pub struct FontOptions {
     pub font_list: Vec<String>,
     pub size: f32,
+    pub width: f32,
     pub bold: bool,
     pub italic: bool,
     pub allow_float_size: bool,
@@ -41,7 +42,11 @@ impl FontOptions {
                     font_options.allow_float_size = true;
                 }
                 if let Ok(parsed_size) = part[1..].parse::<f32>() {
-                    font_options.size = points_to_pixels(parsed_size)
+                    font_options.size = points_to_pixels(parsed_size);
+                }
+            } else if part.starts_with('w') && part.len() > 1 {
+                if let Ok(parsed_size) = part[1..].parse::<f32>() {
+                    font_options.width = points_to_pixels(parsed_size);
                 }
             } else if part == "b" {
                 font_options.bold = true;
@@ -66,6 +71,7 @@ impl Default for FontOptions {
             italic: false,
             allow_float_size: false,
             size: points_to_pixels(DEFAULT_FONT_SIZE),
+            width: 0.0,
             hinting: FontHinting::default(),
             edging: FontEdging::default(),
         }

website/docs/configuration.md

@@ -58,6 +58,8 @@ as such it's also documented in `:h guifont`. But to sum it up and also add Neov
   - are separated from the fonts and themselves through `:` (colons).
   - can be one of the following:
     - `hX` — Sets the font size to `X` points, while `X` can be any (even floating-point) number.
+    - `wX` — Sets the width **relative offset** to be `X` points, while `X` can be again any number.
+        Negative values shift characters closer together, positive values shift them further apart.
     - `b` — Sets the font **bold**.
     - `i` — Sets the font _italic_.
     - `#e-X` (available since 0.10.2) — Sets edge pixels to be drawn opaquely or