add text capabilities

turtle-lib/src/general/fontsize.rs

@@ -0,0 +1,48 @@
+//! `FontSize` type for text rendering
+
+#[derive(Default, Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord)]
+pub struct FontSize(pub u16);
+
+impl FontSize {
+    /// Create a new `FontSize` from a u16 value
+    #[must_use]
+    pub const fn new(size: u16) -> Self {
+        Self(size)
+    }
+
+    /// Get the inner u16 value
+    #[must_use]
+    pub const fn value(&self) -> u16 {
+        self.0
+    }
+}
+
+impl From<u16> for FontSize {
+    fn from(size: u16) -> Self {
+        Self(size)
+    }
+}
+
+impl From<f32> for FontSize {
+    fn from(f: f32) -> Self {
+        Self(f.max(1.0) as u16)
+    }
+}
+
+impl From<i32> for FontSize {
+    fn from(i: i32) -> Self {
+        Self(i.max(1) as u16)
+    }
+}
+
+impl From<i16> for FontSize {
+    fn from(i: i16) -> Self {
+        Self(i.max(1) as u16)
+    }
+}
+
+impl From<usize> for FontSize {
+    fn from(size: usize) -> Self {
+        Self((size as u16).max(1))
+    }
+}