editor: Represent scroll offset with more precision (#39367)

Closes #5355

Release Notes:

- Fixed rendering glitches with files with more than 16 million lines
(that occured due to floating number rounding errors).

---------

Co-authored-by: Smit Barmase <heysmitbarmase@gmail.com>

crates/ui/src/components/keybinding_hint.rs

@@ -249,7 +249,7 @@ impl RenderOnce for KeybindingHint {
                         blur_radius: px(0.),
                         spread_radius: px(0.),
                     }])
-                    .child(self.keybinding.size(rems_from_px(kb_size.0))),
+                    .child(self.keybinding.size(rems_from_px(kb_size))),
             )
             .children(self.suffix)
     }

crates/ui/src/components/list/list_bullet_item.rs

@@ -16,7 +16,7 @@ impl ListBulletItem {
 
 impl RenderOnce for ListBulletItem {
     fn render(self, window: &mut Window, _cx: &mut App) -> impl IntoElement {
-        let line_height = 0.85 * window.line_height();
+        let line_height = window.line_height() * 0.85;
 
         ListItem::new("list-item")
             .selectable(false)

crates/ui/src/styles/typography.rs

@@ -140,8 +140,8 @@ impl TextSize {
             Self::Default => rems_from_px(14.),
             Self::Small => rems_from_px(12.),
             Self::XSmall => rems_from_px(10.),
-            Self::Ui => rems_from_px(theme_settings.ui_font_size(cx).into()),
-            Self::Editor => rems_from_px(theme_settings.buffer_font_size(cx).into()),
+            Self::Ui => rems_from_px(theme_settings.ui_font_size(cx)),
+            Self::Editor => rems_from_px(theme_settings.buffer_font_size(cx)),
         }
     }
 }

crates/ui/src/styles/units.rs

@@ -10,8 +10,8 @@ pub const BASE_REM_SIZE_IN_PX: f32 = 16.;
 ///
 /// For instance, instead of writing `rems(0.875)` you can write `rems_from_px(14.)`
 #[inline(always)]
-pub fn rems_from_px(px: f32) -> Rems {
-    rems(px / BASE_REM_SIZE_IN_PX)
+pub fn rems_from_px(px: impl Into<f32>) -> Rems {
+    rems(px.into() / BASE_REM_SIZE_IN_PX)
 }
 
 /// Returns a [`Length`] corresponding to the specified percentage of the viewport's width.

crates/ui/src/utils/search_input.rs

@@ -1,20 +1,20 @@
-use gpui::Pixels;
+use gpui::{Pixels, px};
 
 pub struct SearchInputWidth;
 
 impl SearchInputWidth {
     /// The container size in which the input stops filling the whole width.
-    pub const THRESHOLD_WIDTH: f32 = 1200.0;
+    pub const THRESHOLD_WIDTH: Pixels = px(1200.0);
 
     /// The maximum width for the search input when the container is larger than the threshold.
-    pub const MAX_WIDTH: f32 = 1200.0;
+    pub const MAX_WIDTH: Pixels = px(1200.0);
 
     /// Calculates the actual width in pixels based on the container width.
     pub fn calc_width(container_width: Pixels) -> Pixels {
-        if container_width.0 < Self::THRESHOLD_WIDTH {
+        if container_width < Self::THRESHOLD_WIDTH {
             container_width
         } else {
-            Pixels(container_width.0.min(Self::MAX_WIDTH))
+            container_width.min(Self::MAX_WIDTH)
         }
     }
 }