0.3.0: TrimString and TrimStringRef

tui/Cargo.toml

@@ -5,14 +5,15 @@ description = "UI metaframework, Ratatui backend."
 version     = { workspace = true }
 
 [dependencies]
-palette      = { version = "0.7.6", features = [ "random" ] }
-rand         = "0.8.5"
-crossterm    = "0.28.1"
-ratatui      = { version = "0.29.0", features = [ "unstable-widget-ref", "underline-color" ] }
-better-panic = "0.3.0"
-konst        = { version = "0.3.16", features = [ "rust_1_83" ] }
-atomic_float = "1"
-quanta       = "0.12.3"
+palette       = { version = "0.7.6", features = [ "random" ] }
+rand          = "0.8.5"
+crossterm     = "0.28.1"
+ratatui       = { version = "0.29.0", features = [ "unstable-widget-ref", "underline-color" ] }
+better-panic  = "0.3.0"
+konst         = { version = "0.3.16", features = [ "rust_1_83" ] }
+atomic_float  = "1"
+quanta        = "0.12.3"
+unicode-width = "0.2"
 
 tengri_input  = { path = "../input"  }
 tengri_output = { path = "../output" }

tui/src/tui_content/tui_string.rs

@@ -0,0 +1,50 @@
+use crate::*;
+use crate::ratatui::prelude::Position;
+use unicode_width::{UnicodeWidthStr, UnicodeWidthChar};
+
+/// Displays an owned [str]-like with fixed maximum width.
+///
+/// Width is computed using [unicode_width].
+pub struct TrimString<T: AsRef<str>>(pub u16, pub T);
+
+impl<'a, T: AsRef<str>> TrimString<T> {
+    fn as_ref (&self) -> TrimStringRef<'_, T> {
+        TrimStringRef(self.0, &self.1)
+    }
+}
+impl<'a, T: AsRef<str>> Content<TuiOut> for TrimString<T> {
+    fn layout (&self, to: [u16; 4]) -> [u16;4] {
+        Content::layout(&self.as_ref(), to)
+    }
+    fn render (&self, to: &mut TuiOut) {
+        Content::render(&self.as_ref(), to)
+    }
+}
+
+/// Displays a borrowed [str]-like with fixed maximum width
+///
+/// Width is computed using [unicode_width].
+pub struct TrimStringRef<'a, T: AsRef<str>>(pub u16, pub &'a T);
+
+impl<T: AsRef<str>> Content<TuiOut> for TrimStringRef<'_, T> {
+    fn layout (&self, to: [u16; 4]) -> [u16;4] {
+        [to.x(), to.y(), to.w().min(self.0).min(self.1.as_ref().width() as u16), to.h()]
+    }
+    fn render (&self, target: &mut TuiOut) {
+        let area = target.area();
+        let mut width: u16 = 0;
+        let mut chars = self.1.as_ref().chars();
+        while let Some(c) = chars.next() {
+            width += c.width().unwrap_or(0) as u16;
+            if width > self.0 || width > area.w() {
+                break
+            }
+            if let Some(cell) = target.buffer.cell_mut(Position {
+                x: area.x() + width,
+                y: area.y()
+            }) {
+                cell.set_char(c);
+            }
+        }
+    }
+}