added FillMode::fill()

style/src/rule.rs

@@ -19,6 +19,53 @@ pub enum FillMode {
     AsymmetricPadding(u16, u16),
 }
 
+impl FillMode {
+    /// Return the starting offset and length of the rule.
+    ///
+    /// * `space` - The space to fill.
+    ///
+    /// # Returns
+    ///
+    /// * (starting_offset, length)
+    pub fn fill(&self, space: f32) -> (f32, f32) {
+        match *self {
+            FillMode::Full => (0.0, space),
+            FillMode::Percent(percent) => {
+                if percent >= 100.0 {
+                    (0.0, space)
+                } else {
+                    let percent_width = (space * percent / 100.0).round();
+
+                    (((space - percent_width) / 2.0).round(), percent_width)
+                }
+            }
+            FillMode::Padded(padding) => {
+                if padding == 0 {
+                    (0.0, space)
+                } else {
+                    let padding = padding as f32;
+                    let mut line_width = space - (padding * 2.0);
+                    if line_width < 0.0 {
+                        line_width = 0.0;
+                    }
+
+                    (padding, line_width)
+                }
+            }
+            FillMode::AsymmetricPadding(first_pad, second_pad) => {
+                let first_pad = first_pad as f32;
+                let second_pad = second_pad as f32;
+                let mut line_width = space - first_pad - second_pad;
+                if line_width < 0.0 {
+                    line_width = 0.0;
+                }
+
+                (first_pad, line_width)
+            }
+        }
+    }
+}
+
 /// The appearance of a rule.
 #[derive(Debug, Clone, Copy)]
 pub struct Style {
@@ -26,7 +73,7 @@ pub struct Style {
     pub color: Color,
     /// The width (thickness) of the rule line.
     pub width: u16,
-    /// The radius of the rectangle corners.
+    /// The radius of the line corners.
     pub radius: u16,
     /// The [`FillMode`] of the rule.
     ///