Support DIM

* Add a color deriver and derive dim colors for all themes.
 * Derive actual bright colors for the OneHalfDark theme while at it.
 * Use dim colors when the DIM flag is set.

Signed-off-by: Mohammad AlSaleh <CE.Mohammad.AlSaleh@gmail.com>

Cargo.lock

@@ -874,6 +874,7 @@ dependencies = [
  "lazy_static",
  "libcosmic",
  "log",
+ "palette",
  "paste",
  "rust-embed",
  "serde",

Cargo.toml

@@ -17,6 +17,7 @@ i18n-embed = { version = "0.13", features = ["fluent-system", "desktop-requester
 i18n-embed-fl = "0.6"
 rust-embed = "6"
 paste = "1.0"
+palette = "0.7"
 
 [dependencies.cosmic-text]
 git = "https://github.com/pop-os/cosmic-text.git"

src/terminal.rs

@@ -85,6 +85,13 @@ fn as_bright(mut color: Color) -> Color {
     color
 }
 
+fn as_dim(mut color: Color) -> Color {
+    if let Color::Named(named) = color {
+        color = Color::Named(named.to_dim());
+    }
+    color
+}
+
 fn convert_color(colors: &Colors, color: Color) -> cosmic_text::Color {
     let rgb = match color {
         Color::Named(named_color) => match colors[named_color] {
@@ -581,12 +588,13 @@ impl Terminal {
 
                     let mut attrs = self.default_attrs;
 
-                    let cell_fg =
+                    let cell_fg = if indexed.cell.flags.contains(Flags::DIM) {
-                        if self.use_bright_bold && indexed.cell.flags.contains(Flags::BOLD) {
+                        as_dim(indexed.cell.fg)
-                            as_bright(indexed.cell.fg)
+                    } else if self.use_bright_bold && indexed.cell.flags.contains(Flags::BOLD) {
-                        } else {
+                        as_bright(indexed.cell.fg)
-                            indexed.cell.fg
+                    } else {
-                        };
+                        indexed.cell.fg
+                    };
 
                     let (mut fg, mut bg) = if indexed.cell.flags.contains(Flags::INVERSE) {
                         (

src/terminal_theme.rs

@@ -2,8 +2,113 @@ use alacritty_terminal::{
     term::color::Colors,
     vte::ansi::{NamedColor, Rgb},
 };
+
+use palette::{encoding::Srgb, rgb::Rgb as PRgb, Okhsl, FromColor, num::Abs};
 use std::collections::HashMap;
 
+// Fill missing dim/bright colors with derived values from normal ones.
+struct ColorDerive {
+    dim_saturation_adjustment: f32,
+    dim_lightness_adjustment: f32,
+    bright_saturation_adjustment: f32,
+    bright_lightness_adjustment: f32,
+}
+
+impl ColorDerive {
+    fn new() -> Self {
+        Self {
+            // The dim flag/escape code is also sometimes described as faint.
+            // So we reduce lightness and saturation to get both effects.
+            dim_saturation_adjustment: -0.2,
+            dim_lightness_adjustment: -0.2,
+            // Normal colors are usually saturated enough. So we default this to 0.0
+            // to avoid pushing colors towards white.
+            bright_saturation_adjustment: 0.0,
+            bright_lightness_adjustment: 0.10,
+        }
+    }
+
+    fn with_dim_lightness_adjustment(self, dim_lightness_adjustment: f32) -> Self {
+        Self { dim_lightness_adjustment, ..self }
+    }
+
+    fn rgb_to_okhsl(c: Rgb) -> Okhsl {
+        let p_rgb = PRgb::<Srgb, u8>::new(c.r, c.g, c.b)
+            .into_format::<f32>();
+        Okhsl::from_color(p_rgb)
+    }
+
+    fn okhsl_to_rgb(c: Okhsl) -> Rgb {
+        let p_rgb = PRgb::<Srgb, _>::from_color(c)
+            .into_format::<u8>();
+        let (r, g, b) = p_rgb.into_components();
+        Rgb{r, g, b}
+    }
+
+    fn color_adj(rgb: Rgb, saturation_adj: f32, lightness_adj: f32) -> Rgb {
+        let mut okhsl = Self::rgb_to_okhsl(rgb);
+
+        okhsl.saturation = (okhsl.saturation + saturation_adj)
+            .max(0.0)
+            .min(1.0);
+        okhsl.lightness = (okhsl.lightness + lightness_adj)
+            .max(0.0)
+            .min(1.0);
+
+        Self::okhsl_to_rgb(okhsl)
+    }
+
+    fn brighten(&self, rgb: Rgb) -> Rgb {
+        let saturation_adj = self.bright_saturation_adjustment;
+        let lightness_adj = self.bright_lightness_adjustment;
+        Self::color_adj(rgb, saturation_adj, lightness_adj)
+    }
+
+    fn dim_and_faint(&self, rgb: Rgb) -> Rgb {
+        let saturation_adj = self.dim_saturation_adjustment;
+        let lightness_adj = self.dim_lightness_adjustment;
+        Self::color_adj(rgb, saturation_adj, lightness_adj)
+    }
+
+    fn fill_missing_brights(&self, colors: &mut Colors) {
+        macro_rules! populate {
+            ($($normal:ident$(,)?)+) => {
+                paste::paste!{
+                    $(
+                        if colors[NamedColor::[<Bright $normal>]].is_none() {
+                            match colors[NamedColor::$normal] {
+                                None => panic!("tried to derive bright color from {} which is not set", stringify!($normal)),
+                                Some(rgb) => colors[NamedColor::[<Bright $normal>]] = Some(self.brighten(rgb)),
+                            }
+                        }
+                    )+
+                }
+            };
+        }
+
+        populate!{ Foreground, Black, Red, Green, Yellow, Blue, Magenta, Cyan, White };
+    }
+
+    fn fill_missing_dims(&self, colors: &mut Colors) {
+        macro_rules! populate {
+            ($($normal:ident$(,)?)+) => {
+                paste::paste!{
+                    $(
+                        if colors[NamedColor::[<Dim $normal>]].is_none() {
+                            match colors[NamedColor::$normal] {
+                                None => panic!("tried to derive dim color from {} which is not set", stringify!($normal)),
+                                Some(rgb) => colors[NamedColor::[<Dim $normal>]] = Some(self.dim_and_faint(rgb)),
+                            }
+                        }
+                    )+
+                }
+            };
+        }
+
+        populate!{ Foreground, Black, Red, Green, Yellow, Blue, Magenta, Cyan, White };
+    }
+}
+
 fn auto_colors() -> Colors {
     let mut colors = Colors::default();
 
@@ -69,18 +174,10 @@ fn cosmic_dark() -> Colors {
     colors[NamedColor::Foreground] = colors[NamedColor::BrightWhite];
     colors[NamedColor::Background] = colors[NamedColor::Black];
     colors[NamedColor::Cursor] = colors[NamedColor::BrightWhite];
-    /*TODO
-    colors[NamedColor::DimBlack] = colors[NamedColor::];
-    colors[NamedColor::DimRed] = colors[NamedColor::];
-    colors[NamedColor::DimGreen] = colors[NamedColor::];
-    colors[NamedColor::DimYellow] = colors[NamedColor::];
-    colors[NamedColor::DimBlue] = colors[NamedColor::];
-    colors[NamedColor::DimMagenta] = colors[NamedColor::];
-    colors[NamedColor::DimCyan] = colors[NamedColor::];
-    colors[NamedColor::DimWhite] = colors[NamedColor::];
-    */
     colors[NamedColor::BrightForeground] = colors[NamedColor::BrightWhite];
-    //TODO colors[NamedColor::DimForeground] = colors[NamedColor::];
+
+    // Fill missing dim colors
+    ColorDerive::new().fill_missing_dims(&mut colors);
 
     colors
 }
@@ -118,18 +215,16 @@ fn cosmic_light() -> Colors {
     colors[NamedColor::Foreground] = colors[NamedColor::Black];
     colors[NamedColor::Background] = colors[NamedColor::BrightWhite];
     colors[NamedColor::Cursor] = colors[NamedColor::Black];
-    /*TODO
+    colors[NamedColor::BrightForeground] = colors[NamedColor::BrightBlack];
-    colors[NamedColor::DimBlack] = colors[NamedColor::];
+
-    colors[NamedColor::DimRed] = colors[NamedColor::];
+    // Fill missing dim colors
-    colors[NamedColor::DimGreen] = colors[NamedColor::];
+    ColorDerive::new()
-    colors[NamedColor::DimYellow] = colors[NamedColor::];
+        // With light backgrounds, the dim and faint descriptions are at odds!
-    colors[NamedColor::DimBlue] = colors[NamedColor::];
+        // To make the color fainter, we would need to increase lightness not decrease it!
-    colors[NamedColor::DimMagenta] = colors[NamedColor::];
+        // But other terminals seem to still dim colors in light themes. So we dim too, but
-    colors[NamedColor::DimCyan] = colors[NamedColor::];
+        // not by much, since normal colors are dim enough already.
-    colors[NamedColor::DimWhite] = colors[NamedColor::];
+        .with_dim_lightness_adjustment(-0.07)
-    */
+        .fill_missing_dims(&mut colors);
-    colors[NamedColor::BrightForeground] = colors[NamedColor::BrightWhite];
-    //TODO colors[NamedColor::DimForeground] = colors[NamedColor::];
 
     colors
 }
@@ -167,18 +262,13 @@ fn gruvbox_dark() -> Colors {
     colors[NamedColor::Foreground] = colors[NamedColor::BrightWhite];
     colors[NamedColor::Background] = colors[NamedColor::Black];
     colors[NamedColor::Cursor] = colors[NamedColor::BrightWhite];
-    /*TODO
-    colors[NamedColor::DimBlack] = colors[NamedColor::];
-    colors[NamedColor::DimRed] = colors[NamedColor::];
-    colors[NamedColor::DimGreen] = colors[NamedColor::];
-    colors[NamedColor::DimYellow] = colors[NamedColor::];
-    colors[NamedColor::DimBlue] = colors[NamedColor::];
-    colors[NamedColor::DimMagenta] = colors[NamedColor::];
-    colors[NamedColor::DimCyan] = colors[NamedColor::];
-    colors[NamedColor::DimWhite] = colors[NamedColor::];
-    */
     colors[NamedColor::BrightForeground] = colors[NamedColor::BrightWhite];
-    //TODO colors[NamedColor::DimForeground] = colors[NamedColor::];
+
+    // Fill missing dim colors
+    ColorDerive::new()
+        // Dim less so colors are readable with default bg
+        .with_dim_lightness_adjustment(-0.15)
+        .fill_missing_dims(&mut colors);
 
     colors
 }
@@ -204,30 +294,21 @@ fn one_half_dark() -> Colors {
     colors[NamedColor::White] = Some(encode_rgb(0xdcdfe4));
 
     colors[NamedColor::BrightBlack] = Some(encode_rgb(0x5d677a));
-    colors[NamedColor::BrightRed] = Some(encode_rgb(0xe06c75));
-    colors[NamedColor::BrightGreen] = Some(encode_rgb(0x98c379));
-    colors[NamedColor::BrightYellow] = Some(encode_rgb(0xe5c07b));
-    colors[NamedColor::BrightBlue] = Some(encode_rgb(0x61afef));
-    colors[NamedColor::BrightMagenta] = Some(encode_rgb(0xc678dd));
-    colors[NamedColor::BrightCyan] = Some(encode_rgb(0x56b6c2));
-    colors[NamedColor::BrightWhite] = Some(encode_rgb(0xdcdfe4));
 
-    // Set special colors
+    // Set this before filling bright colors (including BrightForeground)
-    colors[NamedColor::Foreground] = colors[NamedColor::BrightWhite];
+    colors[NamedColor::Foreground] = colors[NamedColor::White];
+
+    let color_derive = ColorDerive::new();
+
+    // Fill missing bright colors
+    color_derive.fill_missing_brights(&mut colors);
+
+    // Set the rest of special colors
     colors[NamedColor::Background] = colors[NamedColor::Black];
     colors[NamedColor::Cursor] = colors[NamedColor::BrightWhite];
-    /*TODO
+
-    colors[NamedColor::DimBlack] = colors[NamedColor::];
+    // Fill missing dim colors
-    colors[NamedColor::DimRed] = colors[NamedColor::];
+    color_derive.fill_missing_dims(&mut colors);
-    colors[NamedColor::DimGreen] = colors[NamedColor::];
-    colors[NamedColor::DimYellow] = colors[NamedColor::];
-    colors[NamedColor::DimBlue] = colors[NamedColor::];
-    colors[NamedColor::DimMagenta] = colors[NamedColor::];
-    colors[NamedColor::DimCyan] = colors[NamedColor::];
-    colors[NamedColor::DimWhite] = colors[NamedColor::];
-    */
-    colors[NamedColor::BrightForeground] = colors[NamedColor::BrightWhite];
-    //TODO colors[NamedColor::DimForeground] = colors[NamedColor::];
 
     colors
 }
@@ -260,18 +341,13 @@ fn pop_dark() -> Colors {
     colors[NamedColor::Foreground] = Some(encode_rgb(242, 242, 242));
     colors[NamedColor::Background] = Some(encode_rgb(51, 51, 51));
     colors[NamedColor::Cursor] = colors[NamedColor::BrightWhite];
-    /*TODO
-    colors[NamedColor::DimBlack] = colors[NamedColor::];
-    colors[NamedColor::DimRed] = colors[NamedColor::];
-    colors[NamedColor::DimGreen] = colors[NamedColor::];
-    colors[NamedColor::DimYellow] = colors[NamedColor::];
-    colors[NamedColor::DimBlue] = colors[NamedColor::];
-    colors[NamedColor::DimMagenta] = colors[NamedColor::];
-    colors[NamedColor::DimCyan] = colors[NamedColor::];
-    colors[NamedColor::DimWhite] = colors[NamedColor::];
-    */
     colors[NamedColor::BrightForeground] = colors[NamedColor::BrightWhite];
-    //TODO colors[NamedColor::DimForeground] = colors[NamedColor::];
+
+    // Fill missing dim colors
+    ColorDerive::new()
+        // Dim less so colors are readable with default bg
+        .with_dim_lightness_adjustment(-0.05)
+        .fill_missing_dims(&mut colors);
 
     colors
 }