Draw scrollbar on top of scrollable content

2 files changed, 41 insertions, 39 deletions

diff --git a/wgpu/src/renderer.rs b/wgpu/src/renderer.rs
index bb7cb858..f0be0860 100644
--- a/wgpu/src/renderer.rs
+++ b/wgpu/src/renderer.rs
@@ -47,7 +47,6 @@ pub struct Layer<'a> {
     quads: Vec<Quad>,
     images: Vec<Image>,
     text: Vec<wgpu_glyph::Section<'a>>,
-    layers: Vec<Layer<'a>>,
 }
 
 impl<'a> Layer<'a> {
@@ -58,7 +57,6 @@ impl<'a> Layer<'a> {
             quads: Vec::new(),
             images: Vec::new(),
             text: Vec::new(),
-            layers: Vec::new(),
         }
     }
 }
@@ -149,7 +147,8 @@ impl Renderer {
             depth_stencil_attachment: None,
         });
 
-        let mut layer = Layer::new(
+        let mut layers = Vec::new();
+        let mut current = Layer::new(
             Rectangle {
                 x: 0,
                 y: 0,
@@ -159,8 +158,17 @@ impl Renderer {
             0,
         );
 
-        self.draw_primitive(primitive, &mut layer);
-        self.flush(target.transformation, &layer, &mut encoder, &frame.view);
+        self.draw_primitive(primitive, &mut current, &mut layers);
+        layers.push(current);
+
+        for layer in layers {
+            self.flush(
+                target.transformation,
+                &layer,
+                &mut encoder,
+                &frame.view,
+            );
+        }
 
         self.queue.submit(&[encoder.finish()]);
 
@@ -171,13 +179,14 @@ impl Renderer {
         &mut self,
         primitive: &'a Primitive,
         layer: &mut Layer<'a>,
+        layers: &mut Vec<Layer<'a>>,
     ) {
         match primitive {
             Primitive::None => {}
             Primitive::Group { primitives } => {
                 // TODO: Inspect a bit and regroup (?)
                 for primitive in primitives {
-                    self.draw_primitive(primitive, layer)
+                    self.draw_primitive(primitive, layer, layers)
                 }
             }
             Primitive::Text {
@@ -277,9 +286,9 @@ impl Renderer {
                 );
 
                 // TODO: Primitive culling
-                self.draw_primitive(content, &mut new_layer);
+                self.draw_primitive(content, &mut new_layer, layers);
 
-                layer.layers.push(new_layer);
+                layers.push(new_layer);
             }
         }
     }
@@ -338,10 +347,6 @@ impl Renderer {
                 )
                 .expect("Draw text");
         }
-
-        for layer in layer.layers.iter() {
-            self.flush(transformation, layer, encoder, target);
-        }
     }
 }
 
diff --git a/wgpu/src/renderer/scrollable.rs b/wgpu/src/renderer/scrollable.rs
index 5b93a765..43dddeed 100644
--- a/wgpu/src/renderer/scrollable.rs
+++ b/wgpu/src/renderer/scrollable.rs
@@ -34,34 +34,31 @@ impl scrollable::Renderer for Renderer {
         };
 
         (
-            Primitive::Group {
-                primitives: if is_mouse_over
-                    && content_bounds.height > bounds.height
-                {
-                    let ratio = bounds.height / content_bounds.height;
-                    let scrollbar_height = bounds.height * ratio;
-                    let y_offset = offset as f32 * ratio;
+            if is_mouse_over && content_bounds.height > bounds.height {
+                let ratio = bounds.height / content_bounds.height;
+                let scrollbar_height = bounds.height * ratio;
+                let y_offset = offset as f32 * ratio;
 
-                    let scrollbar = Primitive::Quad {
-                        bounds: Rectangle {
-                            x: bounds.x + bounds.width - 12.0,
-                            y: bounds.y + y_offset,
-                            width: 10.0,
-                            height: scrollbar_height,
-                        },
-                        background: Background::Color(Color {
-                            r: 0.0,
-                            g: 0.0,
-                            b: 0.0,
-                            a: 0.5,
-                        }),
-                        border_radius: 5,
-                    };
-
-                    vec![primitive, scrollbar]
-                } else {
-                    vec![primitive]
-                },
+                let scrollbar = Primitive::Quad {
+                    bounds: Rectangle {
+                        x: bounds.x + bounds.width - 12.0,
+                        y: bounds.y + y_offset,
+                        width: 10.0,
+                        height: scrollbar_height,
+                    },
+                    background: Background::Color(Color {
+                        r: 0.0,
+                        g: 0.0,
+                        b: 0.0,
+                        a: 0.7,
+                    }),
+                    border_radius: 5,
+                };
+                Primitive::Group {
+                    primitives: vec![primitive, scrollbar],
+                }
+            } else {
+                primitive
             },
             mouse_cursor,
         )