Implement state-less scrolling in TextInput

wgpu/src/renderer/text_input.rs

@@ -87,10 +87,7 @@ impl text_input::Renderer for Renderer {
             vertical_alignment: VerticalAlignment::Center,
         };
 
-        let content = Primitive::Clip {
+        let (contents_primitive, offset) = if text_input.state.is_focused {
-            bounds: text_bounds,
-            offset: Vector::new(0, 0),
-            content: Box::new(if text_input.state.is_focused {
             use wgpu_glyph::{GlyphCruncher, Scale, Section};
 
             let text_before_cursor = &text_input
@@ -110,8 +107,8 @@ impl text_input::Renderer for Renderer {
                 .map(|bounds| bounds.width().round())
                 .unwrap_or(0.0);
 
-                let spaces_at_the_end = text_before_cursor.len()
+            let spaces_at_the_end =
-                    - text_before_cursor.trim_end().len();
+                text_before_cursor.len() - text_before_cursor.trim_end().len();
 
             if spaces_at_the_end > 0 {
                 let space_width = {
@@ -140,17 +137,29 @@ impl text_input::Renderer for Renderer {
                 border_radius: 0,
             };
 
+            (
                 Primitive::Group {
                     primitives: vec![value, cursor],
-                }
+                },
+                Vector::new(
+                    ((text_value_width + 5.0) - text_bounds.width).max(0.0)
+                        as u32,
+                    0,
+                ),
+            )
         } else {
-                value
+            (value, Vector::new(0, 0))
-            }),
+        };
+
+        let contents = Primitive::Clip {
+            bounds: text_bounds,
+            offset,
+            content: Box::new(contents_primitive),
         };
 
         (
             Primitive::Group {
-                primitives: vec![border, input, content],
+                primitives: vec![border, input, contents],
             },
             if is_mouse_over {
                 MouseCursor::Text