Add gradient support for the insert hint

Implement it via FocusRing which already handles SolidColor vs. Border
render element.

5 files changed, 100 insertions, 17 deletions

diff --git a/niri-config/src/lib.rs b/niri-config/src/lib.rs
index d8613def..042cf6ba 100644
--- a/niri-config/src/lib.rs
+++ b/niri-config/src/lib.rs
@@ -597,6 +597,8 @@ pub struct InsertHint {
     pub off: bool,
     #[knuffel(child, default = Self::default().color)]
     pub color: Color,
+    #[knuffel(child)]
+    pub gradient: Option<Gradient>,
 }
 
 impl Default for InsertHint {
@@ -604,6 +606,7 @@ impl Default for InsertHint {
         Self {
             off: false,
             color: Color::from_rgba8_unpremul(127, 200, 255, 128),
+            gradient: None,
         }
     }
 }
@@ -3051,6 +3054,7 @@ mod tests {
 
                 insert-hint {
                     color "rgb(255, 200, 127)"
+                    gradient from="rgba(10, 20, 30, 1.0)" to="#0080ffff" relative-to="workspace-view"
                 }
             }
 
@@ -3253,6 +3257,16 @@ mod tests {
                     insert_hint: InsertHint {
                         off: false,
                         color: Color::from_rgba8_unpremul(255, 200, 127, 255),
+                        gradient: Some(Gradient {
+                            from: Color::from_rgba8_unpremul(10, 20, 30, 255),
+                            to: Color::from_rgba8_unpremul(0, 128, 255, 255),
+                            angle: 180,
+                            relative_to: GradientRelativeTo::WorkspaceView,
+                            in_: GradientInterpolation {
+                                color_space: GradientColorSpace::Srgb,
+                                hue_interpolation: HueInterpolation::Shorter,
+                            },
+                        }),
                     },
                     preset_column_widths: vec![
                         PresetSize::Proportion(0.25),
diff --git a/src/layout/insert_hint_element.rs b/src/layout/insert_hint_element.rs
new file mode 100644
index 00000000..5f70295c
--- /dev/null
+++ b/src/layout/insert_hint_element.rs
@@ -0,0 +1,61 @@
+use niri_config::{CornerRadius, FloatOrInt};
+use smithay::utils::{Logical, Point, Rectangle, Size};
+
+use super::focus_ring::{FocusRing, FocusRingRenderElement};
+use crate::render_helpers::renderer::NiriRenderer;
+
+#[derive(Debug)]
+pub struct InsertHintElement {
+    inner: FocusRing,
+}
+
+pub type InsertHintRenderElement = FocusRingRenderElement;
+
+impl InsertHintElement {
+    pub fn new(config: niri_config::InsertHint) -> Self {
+        Self {
+            inner: FocusRing::new(niri_config::FocusRing {
+                off: config.off,
+                width: FloatOrInt(0.),
+                active_color: config.color,
+                inactive_color: config.color,
+                active_gradient: config.gradient,
+                inactive_gradient: config.gradient,
+            }),
+        }
+    }
+
+    pub fn update_config(&mut self, config: niri_config::InsertHint) {
+        self.inner.update_config(niri_config::FocusRing {
+            off: config.off,
+            width: FloatOrInt(0.),
+            active_color: config.color,
+            inactive_color: config.color,
+            active_gradient: config.gradient,
+            inactive_gradient: config.gradient,
+        });
+    }
+
+    pub fn update_shaders(&mut self) {
+        self.inner.update_shaders();
+    }
+
+    pub fn update_render_elements(
+        &mut self,
+        size: Size<f64, Logical>,
+        view_rect: Rectangle<f64, Logical>,
+        radius: CornerRadius,
+        scale: f64,
+    ) {
+        self.inner
+            .update_render_elements(size, true, false, view_rect, radius, scale);
+    }
+
+    pub fn render(
+        &self,
+        renderer: &mut impl NiriRenderer,
+        location: Point<f64, Logical>,
+    ) -> impl Iterator<Item = FocusRingRenderElement> {
+        self.inner.render(renderer, location)
+    }
+}
diff --git a/src/layout/mod.rs b/src/layout/mod.rs
index 1493152f..1c531b51 100644
--- a/src/layout/mod.rs
+++ b/src/layout/mod.rs
@@ -64,6 +64,7 @@ use crate::window::ResolvedWindowRules;
 
 pub mod closing_window;
 pub mod focus_ring;
+pub mod insert_hint_element;
 pub mod monitor;
 pub mod opening_window;
 pub mod tile;
diff --git a/src/layout/workspace.rs b/src/layout/workspace.rs
index 0f378abc..c8b3d5ee 100644
--- a/src/layout/workspace.rs
+++ b/src/layout/workspace.rs
@@ -8,7 +8,6 @@ use niri_config::{
 };
 use niri_ipc::SizeChange;
 use ordered_float::NotNan;
-use smithay::backend::renderer::element::Kind;
 use smithay::backend::renderer::gles::GlesRenderer;
 use smithay::desktop::{layer_map_for_output, Window};
 use smithay::output::Output;
@@ -17,13 +16,13 @@ use smithay::reexports::wayland_server::protocol::wl_surface::WlSurface;
 use smithay::utils::{Logical, Point, Rectangle, Scale, Serial, Size, Transform};
 
 use super::closing_window::{ClosingWindow, ClosingWindowRenderElement};
+use super::insert_hint_element::{InsertHintElement, InsertHintRenderElement};
 use super::tile::{Tile, TileRenderElement, TileRenderSnapshot};
 use super::{ConfigureIntent, InteractiveResizeData, LayoutElement, Options, RemovedTile};
 use crate::animation::Animation;
 use crate::input::swipe_tracker::SwipeTracker;
 use crate::niri_render_elements;
 use crate::render_helpers::renderer::NiriRenderer;
-use crate::render_helpers::solid_color::{SolidColorBuffer, SolidColorRenderElement};
 use crate::render_helpers::RenderTarget;
 use crate::utils::id::IdCounter;
 use crate::utils::transaction::{Transaction, TransactionBlocker};
@@ -111,8 +110,8 @@ pub struct Workspace<W: LayoutElement> {
     /// Indication where an interactively-moved window is about to be placed.
     insert_hint: Option<InsertHint>,
 
-    /// Buffer for the insert hint.
-    insert_hint_buffer: SolidColorBuffer,
+    /// Insert hint element for rendering.
+    insert_hint_element: InsertHintElement,
 
     /// Configurable properties of the layout as received from the parent monitor.
     pub(super) base_options: Rc<Options>,
@@ -173,6 +172,7 @@ niri_render_elements! {
     WorkspaceRenderElement<R> => {
         Tile = TileRenderElement<R>,
         ClosingWindow = ClosingWindowRenderElement,
+        InsertHint = InsertHintRenderElement,
     }
 }
 
@@ -440,7 +440,7 @@ impl<W: LayoutElement> Workspace<W> {
             view_offset_before_fullscreen: None,
             closing_windows: vec![],
             insert_hint: None,
-            insert_hint_buffer: SolidColorBuffer::new((0., 0.), [0., 0., 0., 1.]),
+            insert_hint_element: InsertHintElement::new(options.insert_hint),
             base_options,
             options,
             name: config.map(|c| c.name.0),
@@ -480,7 +480,7 @@ impl<W: LayoutElement> Workspace<W> {
             view_offset_before_fullscreen: None,
             closing_windows: vec![],
             insert_hint: None,
-            insert_hint_buffer: SolidColorBuffer::new((0., 0.), [0., 0., 0., 1.]),
+            insert_hint_element: InsertHintElement::new(options.insert_hint),
             base_options,
             options,
             name: config.map(|c| c.name.0),
@@ -562,8 +562,13 @@ impl<W: LayoutElement> Workspace<W> {
 
         if let Some(insert_hint) = &self.insert_hint {
             if let Some(area) = self.insert_hint_area(insert_hint) {
-                self.insert_hint_buffer
-                    .update(area.size, self.options.insert_hint.color.to_array_premul());
+                let view_rect = Rectangle::from_loc_and_size(area.loc.upscale(-1.), view_size);
+                self.insert_hint_element.update_render_elements(
+                    area.size,
+                    view_rect,
+                    Default::default(),
+                    self.scale.fractional_scale(),
+                );
             }
         }
     }
@@ -577,6 +582,8 @@ impl<W: LayoutElement> Workspace<W> {
             data.update(column);
         }
 
+        self.insert_hint_element.update_config(options.insert_hint);
+
         self.base_options = base_options;
         self.options = options;
     }
@@ -587,6 +594,8 @@ impl<W: LayoutElement> Workspace<W> {
                 tile.update_shaders();
             }
         }
+
+        self.insert_hint_element.update_shaders();
     }
 
     pub fn windows(&self) -> impl Iterator<Item = &W> + '_ {
@@ -2672,14 +2681,10 @@ impl<W: LayoutElement> Workspace<W> {
         // Draw the insert hint.
         if let Some(insert_hint) = &self.insert_hint {
             if let Some(area) = self.insert_hint_area(insert_hint) {
-                rv.push(
-                    TileRenderElement::SolidColor(SolidColorRenderElement::from_buffer(
-                        &self.insert_hint_buffer,
-                        area.loc,
-                        1.,
-                        Kind::Unspecified,
-                    ))
-                    .into(),
+                rv.extend(
+                    self.insert_hint_element
+                        .render(renderer, area.loc)
+                        .map(WorkspaceRenderElement::InsertHint),
                 );
             }
         }
diff --git a/wiki/Configuration:-Layout.md b/wiki/Configuration:-Layout.md
index 02921b48..c7a68835 100644
--- a/wiki/Configuration:-Layout.md
+++ b/wiki/Configuration:-Layout.md
@@ -45,6 +45,7 @@ layout {
     insert-hint {
         // off
         color "#ffc87f80"
+        // gradient from="#ffbb6680" to="#ffc88080" angle=45 relative-to="workspace-view"
     }
 
     struts {
@@ -316,13 +317,14 @@ Settings for the window insert position hint during an interactive window move.
 
 `off` disables the insert hint altogether.
 
-`color` lets you change the color of the hint and has the same syntax as colors in border and focus ring.
+`color` and `gradient` let you change the color of the hint and have the same syntax as colors and gradients in border and focus ring.
 
 ```kdl
 layout {
     insert-hint {
         // off
         color "#ffc87f80"
+        gradient from="#ffbb6680" to="#ffc88080" angle=45 relative-to="workspace-view"
     }
 }
 ```