Clip text to viewport bounds instead of layout bounds

core/src/renderer/null.rs

@@ -64,6 +64,7 @@ impl text::Renderer for Null {
         _paragraph: &Self::Paragraph,
         _position: Point,
         _color: Color,
+        _viewport: Rectangle,
     ) {
     }
 
@@ -72,6 +73,7 @@ impl text::Renderer for Null {
         _editor: &Self::Editor,
         _position: Point,
         _color: Color,
+        _viewport: Rectangle,
     ) {
     }
 
@@ -80,6 +82,7 @@ impl text::Renderer for Null {
         _paragraph: Text<'_, Self::Font>,
         _position: Point,
         _color: Color,
+        _viewport: Rectangle,
     ) {
     }
 }

core/src/text.rs

@@ -9,7 +9,7 @@ pub use highlighter::Highlighter;
 pub use paragraph::Paragraph;
 
 use crate::alignment;
-use crate::{Color, Pixels, Point, Size};
+use crate::{Color, Pixels, Point, Rectangle, Size};
 
 use std::borrow::Cow;
 use std::hash::{Hash, Hasher};
@@ -202,6 +202,7 @@ pub trait Renderer: crate::Renderer {
         text: &Self::Paragraph,
         position: Point,
         color: Color,
+        viewport: Rectangle,
     );
 
     /// Draws the given [`Editor`] at the given position and with the given
@@ -211,6 +212,7 @@ pub trait Renderer: crate::Renderer {
         editor: &Self::Editor,
         position: Point,
         color: Color,
+        viewport: Rectangle,
     );
 
     /// Draws the given [`Text`] at the given position and with the given
@@ -220,5 +222,6 @@ pub trait Renderer: crate::Renderer {
         text: Text<'_, Self::Font>,
         position: Point,
         color: Color,
+        viewport: Rectangle,
     );
 }

core/src/widget/text.rs

@@ -172,7 +172,7 @@ where
         style: &renderer::Style,
         layout: Layout<'_>,
         _cursor_position: mouse::Cursor,
-        _viewport: &Rectangle,
+        viewport: &Rectangle,
     ) {
         let state = tree.state.downcast_ref::<State<Renderer::Paragraph>>();
 
@@ -182,6 +182,7 @@ where
             layout,
             state,
             theme.appearance(self.style.clone()),
+            viewport,
         );
     }
 }
@@ -244,6 +245,7 @@ pub fn draw<Renderer>(
     layout: Layout<'_>,
     state: &State<Renderer::Paragraph>,
     appearance: Appearance,
+    viewport: &Rectangle,
 ) where
     Renderer: text::Renderer,
 {
@@ -266,6 +268,7 @@ pub fn draw<Renderer>(
         paragraph,
         Point::new(x, y),
         appearance.color.unwrap_or(style.text_color),
+        *viewport,
     );
 }