[refactor] Remove Option wrappers around colors and line styles

Just use transparency instead of None

egui/src/containers/collapsing_header.rs

@@ -123,8 +123,8 @@ pub fn paint_icon(ui: &mut Ui, openness: f32, response: &Response) {
     ui.painter().add(PaintCmd::Path {
         path: Path::from_point_loop(&points),
         closed: true,
-        fill: None,
-        outline: Some(LineStyle::new(stroke_width, stroke_color)),
+        fill: Default::default(),
+        outline: LineStyle::new(stroke_width, stroke_color),
     });
 }
 
@@ -229,10 +229,10 @@ impl CollapsingHeader {
         painter.set(
             bg_index,
             PaintCmd::Rect {
+                rect: response.rect,
                 corner_radius: ui.style().interact(&response).corner_radius,
                 fill: ui.style().interact(&response).bg_fill,
-                outline: None,
-                rect: response.rect,
+                outline: Default::default(),
             },
         );
 

egui/src/containers/frame.rs

@@ -8,8 +8,8 @@ pub struct Frame {
     // On each side
     pub margin: Vec2,
     pub corner_radius: f32,
-    pub fill: Option<Srgba>,
-    pub outline: Option<LineStyle>,
+    pub fill: Srgba,
+    pub outline: LineStyle,
 }
 
 impl Frame {
@@ -17,7 +17,7 @@ impl Frame {
         Self {
             margin: style.spacing.window_padding,
             corner_radius: style.visuals.window_corner_radius,
-            fill: Some(style.visuals.background_fill),
+            fill: style.visuals.background_fill,
             outline: style.visuals.interacted.inactive.bg_outline, // because we can resize windows
         }
     }
@@ -26,8 +26,8 @@ impl Frame {
         Self {
             margin: Vec2::splat(1.0),
             corner_radius: 0.0,
-            fill: None,
-            outline: Some(LineStyle::new(0.5, Srgba::gray(128))),
+            fill: Default::default(),
+            outline: LineStyle::new(0.5, Srgba::gray(128)),
         }
     }
 
@@ -35,8 +35,8 @@ impl Frame {
         Self {
             margin: Vec2::splat(1.0),
             corner_radius: 2.0,
-            fill: Some(style.visuals.background_fill),
-            outline: Some(LineStyle::new(1.0, Srgba::gray(128))),
+            fill: style.visuals.background_fill,
+            outline: LineStyle::new(1.0, Srgba::gray(128)),
         }
     }
 
@@ -44,17 +44,17 @@ impl Frame {
         Self {
             margin: style.spacing.window_padding,
             corner_radius: 5.0,
-            fill: Some(style.visuals.background_fill),
-            outline: Some(LineStyle::new(1.0, Srgba::gray(128))),
+            fill: style.visuals.background_fill,
+            outline: LineStyle::new(1.0, Srgba::gray(128)),
         }
     }
 
-    pub fn fill(mut self, fill: Option<Srgba>) -> Self {
+    pub fn fill(mut self, fill: Srgba) -> Self {
         self.fill = fill;
         self
     }
 
-    pub fn outline(mut self, outline: Option<LineStyle>) -> Self {
+    pub fn outline(mut self, outline: LineStyle) -> Self {
         self.outline = outline;
         self
     }

egui/src/containers/resize.rs

@@ -237,8 +237,8 @@ impl Resize {
             ui.painter().add(paint::PaintCmd::Rect {
                 rect,
                 corner_radius: 3.0,
-                fill: None,
-                outline: Some(ui.style().visuals.thin_outline),
+                fill: Default::default(),
+                outline: ui.style().visuals.thin_outline,
             });
         }
 

egui/src/containers/scroll_area.rs

@@ -243,14 +243,14 @@ impl Prepared {
             ui.painter().add(paint::PaintCmd::Rect {
                 rect: outer_scroll_rect,
                 corner_radius,
-                fill: Some(ui.style().visuals.dark_bg_color),
-                outline: None,
+                fill: ui.style().visuals.dark_bg_color,
+                outline: Default::default(),
             });
 
             ui.painter().add(paint::PaintCmd::Rect {
                 rect: handle_rect.expand(-2.0),
                 corner_radius,
-                fill: Some(handle_fill),
+                fill: handle_fill,
                 outline: handle_outline,
             });
         }

egui/src/containers/window.rs

@@ -311,12 +311,11 @@ impl<'open> Window<'open> {
     }
 }
 
-fn paint_resize_corner(ui: &mut Ui, outer_rect: Rect, frame_outline: Option<LineStyle>) {
+fn paint_resize_corner(ui: &mut Ui, outer_rect: Rect, outline: LineStyle) {
     let corner_size = Vec2::splat(ui.style().visuals.resize_corner_size);
     let handle_offset = -Vec2::splat(2.0);
     let corner_rect =
         Rect::from_min_size(outer_rect.max - corner_size + handle_offset, corner_size);
-    let outline = frame_outline.unwrap_or_else(|| LineStyle::new(1.0, color::GRAY));
     crate::resize::paint_resize_corner_with_style(ui, &corner_rect, outline);
 }
 
@@ -566,7 +565,7 @@ fn paint_frame_interaction(
     ui.painter().add(PaintCmd::Path {
         path,
         closed: false,
-        fill: None,
+        fill: Default::default(),
         outline: visuals.bg_outline,
     });
 }
@@ -671,7 +670,7 @@ impl TitleBar {
             let y = content_rect.top() + ui.style().spacing.item_spacing.y * 0.5;
             ui.painter().line_segment(
                 [pos2(left, y), pos2(right, y)],
-                ui.style().visuals.interacted.inactive.bg_outline.unwrap(),
+                ui.style().visuals.interacted.inactive.bg_outline,
             );
         }
 

egui/src/demos/app.rs

@@ -579,12 +579,12 @@ impl BoxPainting {
         for i in 0..self.num_boxes {
             cmds.push(PaintCmd::Rect {
                 corner_radius: self.corner_radius,
-                fill: Some(Srgba::gray(64)),
+                fill: Srgba::gray(64),
                 rect: Rect::from_min_size(
                     pos2(10.0 + pos.x + (i as f32) * (self.size.x * 1.1), pos.y),
                     self.size,
                 ),
-                outline: Some(LineStyle::new(self.stroke_width, WHITE)),
+                outline: LineStyle::new(self.stroke_width, WHITE),
             });
         }
         ui.painter().extend(cmds);
@@ -655,8 +655,8 @@ impl Painting {
                 painter.add(PaintCmd::Path {
                     path: Path::from_open_points(&points),
                     closed: false,
-                    outline: Some(LineStyle::new(self.line_width, LIGHT_GRAY)),
-                    fill: None,
+                    outline: LineStyle::new(self.line_width, LIGHT_GRAY),
+                    fill: Default::default(),
                 });
             }
         }

egui/src/demos/fractal_clock.rs

@@ -37,7 +37,7 @@ impl FractalClock {
             .default_rect(ctx.rect().expand(-42.0))
             .scroll(false)
             // Dark background frame to make it pop:
-            .frame(Frame::window(&ctx.style()).fill(Some(Srgba::black_alpha(250))))
+            .frame(Frame::window(&ctx.style()).fill(Srgba::black_alpha(250)))
             .show(ctx, |ui| self.ui(ui));
     }
 
@@ -54,8 +54,8 @@ impl FractalClock {
         self.fractal_ui(&painter);
 
         Frame::popup(ui.style())
-            .fill(Some(Rgba::luminance_alpha(0.02, 0.5).into()))
-            .outline(None)
+            .fill(Rgba::luminance_alpha(0.02, 0.5).into())
+            .outline(LineStyle::none())
             .show(&mut ui.left_column(320.0), |ui| {
                 CollapsingHeader::new("Settings").show(ui, |ui| self.options_ui(ui));
             });

egui/src/demos/toggle_switch.rs

@@ -36,16 +36,16 @@ pub fn toggle(ui: &mut Ui, on: &mut bool) -> Response {
     ui.painter().add(PaintCmd::Rect {
         rect,
         corner_radius: radius,
+        fill: lerp(off_color..=on_color, how_on).into(),
         outline: style.bg_outline,
-        fill: Some(lerp(off_color..=on_color, how_on).into()),
     });
     // Animate the circle from left to right:
     let circle_x = lerp((rect.left() + radius)..=(rect.right() - radius), how_on);
     ui.painter().add(PaintCmd::Circle {
         center: pos2(circle_x, rect.center().y),
         radius: 0.75 * radius,
-        outline: Some(style.line_style()),
-        fill: Some(style.main_fill),
+        fill: style.main_fill,
+        outline: style.line_style(),
     });
 
     // All done! Return the response so the user can check what happened

egui/src/lib.rs

@@ -74,7 +74,7 @@ pub use {
     layout::*,
     math::*,
     memory::Memory,
-    paint::{color, PaintJobs, Rgba, Srgba, TextStyle, Texture},
+    paint::{color, LineStyle, PaintJobs, Rgba, Srgba, TextStyle, Texture},
     painter::Painter,
     style::Style,
     types::*,

egui/src/menu.rs

@@ -15,7 +15,7 @@
 //! }
 //! ```
 
-use crate::{widgets::*, *};
+use crate::{color::TRANSPARENT, paint::LineStyle, widgets::*, *};
 
 /// What is saved between frames.
 #[derive(Clone, Copy, Debug)]
@@ -62,12 +62,12 @@ pub fn bar<R>(ui: &mut Ui, add_contents: impl FnOnce(&mut Ui) -> R) -> (R, Rect)
         Frame::menu_bar(ui.style()).show(ui, |ui| {
             let mut style = ui.style().clone();
             style.spacing.button_padding = vec2(2.0, 0.0);
-            // style.visuals.interacted.active.bg_fill = None;
-            style.visuals.interacted.active.bg_outline = None;
-            // style.visuals.interacted.hovered.bg_fill = None;
-            style.visuals.interacted.hovered.bg_outline = None;
-            style.visuals.interacted.inactive.bg_fill = None;
-            style.visuals.interacted.inactive.bg_outline = None;
+            // style.visuals.interacted.active.bg_fill = TRANSPARENT;
+            style.visuals.interacted.active.bg_outline = LineStyle::none();
+            // style.visuals.interacted.hovered.bg_fill = TRANSPARENT;
+            style.visuals.interacted.hovered.bg_outline = LineStyle::none();
+            style.visuals.interacted.inactive.bg_fill = TRANSPARENT;
+            style.visuals.interacted.inactive.bg_outline = LineStyle::none();
             ui.set_style(style);
 
             // Take full width and fixed height:
@@ -128,12 +128,12 @@ fn menu_impl<'c>(
                 resize.show(ui, |ui| {
                     let mut style = ui.style().clone();
                     style.spacing.button_padding = vec2(2.0, 0.0);
-                    // style.visuals.interacted.active.bg_fill = None;
-                    style.visuals.interacted.active.bg_outline = None;
-                    // style.visuals.interacted.hovered.bg_fill = None;
-                    style.visuals.interacted.hovered.bg_outline = None;
-                    style.visuals.interacted.inactive.bg_fill = None;
-                    style.visuals.interacted.inactive.bg_outline = None;
+                    // style.visuals.interacted.active.bg_fill = TRANSPARENT;
+                    style.visuals.interacted.active.bg_outline = LineStyle::none();
+                    // style.visuals.interacted.hovered.bg_fill = TRANSPARENT;
+                    style.visuals.interacted.hovered.bg_outline = LineStyle::none();
+                    style.visuals.interacted.inactive.bg_fill = TRANSPARENT;
+                    style.visuals.interacted.inactive.bg_outline = LineStyle::none();
                     ui.set_style(style);
                     ui.set_layout(Layout::justified(Direction::Vertical));
                     add_contents(ui)

egui/src/paint/command.rs

@@ -11,8 +11,8 @@ pub enum PaintCmd {
     Circle {
         center: Pos2,
         radius: f32,
-        fill: Option<Srgba>,
-        outline: Option<LineStyle>,
+        fill: Srgba,
+        outline: LineStyle,
     },
     LineSegment {
         points: [Pos2; 2],
@@ -21,14 +21,14 @@ pub enum PaintCmd {
     Path {
         path: Path,
         closed: bool,
-        fill: Option<Srgba>,
-        outline: Option<LineStyle>,
+        fill: Srgba,
+        outline: LineStyle,
     },
     Rect {
         rect: Rect,
         corner_radius: f32,
-        fill: Option<Srgba>,
-        outline: Option<LineStyle>,
+        fill: Srgba,
+        outline: LineStyle,
     },
     Text {
         /// Top left corner of the first character.
@@ -41,7 +41,7 @@ pub enum PaintCmd {
     Triangles(Triangles),
 }
 
-#[derive(Clone, Copy, Debug)]
+#[derive(Clone, Copy, Debug, Default)]
 #[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct LineStyle {
     pub width: f32,
@@ -49,6 +49,10 @@ pub struct LineStyle {
 }
 
 impl LineStyle {
+    pub fn none() -> Self {
+        Self::new(0.0, crate::color::TRANSPARENT)
+    }
+
     pub fn new(width: impl Into<f32>, color: impl Into<Srgba>) -> Self {
         Self {
             width: width.into(),

egui/src/paint/tessellator.rs

@@ -7,7 +7,7 @@
 
 use {
     super::{
-        color::{self, srgba, Rgba, Srgba},
+        color::{self, srgba, Rgba, Srgba, TRANSPARENT},
         fonts::Fonts,
         LineStyle, PaintCmd,
     },
@@ -427,7 +427,7 @@ pub fn paint_path_outline(
     options: PaintOptions,
     out: &mut Triangles,
 ) {
-    if style.color == color::TRANSPARENT {
+    if style.width <= 0.0 || style.color == color::TRANSPARENT {
         return;
     }
 
@@ -604,12 +604,8 @@ pub fn tessellate_paint_command(
         } => {
             if radius > 0.0 {
                 path.add_circle(center, radius);
-                if let Some(fill) = fill {
-                    fill_closed_path(&path.0, fill, options, out);
-                }
-                if let Some(line_style) = outline {
-                    paint_path_outline(&path.0, Closed, line_style, options, out);
-                }
+                fill_closed_path(&path.0, fill, options, out);
+                paint_path_outline(&path.0, Closed, outline, options, out);
             }
         }
         PaintCmd::Triangles(triangles) => {
@@ -626,17 +622,15 @@ pub fn tessellate_paint_command(
             outline,
         } => {
             if path.len() >= 2 {
-                if let Some(fill) = fill {
+                if fill != TRANSPARENT {
                     debug_assert!(
                         closed,
                         "You asked to fill a path that is not closed. That makes no sense."
                     );
                     fill_closed_path(&path.0, fill, options, out);
                 }
-                if let Some(line_style) = outline {
-                    let typ = if closed { Closed } else { Open };
-                    paint_path_outline(&path.0, typ, line_style, options, out);
-                }
+                let typ = if closed { Closed } else { Open };
+                paint_path_outline(&path.0, typ, outline, options, out);
             }
         }
         PaintCmd::Rect {
@@ -652,12 +646,8 @@ pub fn tessellate_paint_command(
                 rect.max = rect.max.min(pos2(1e7, 1e7));
 
                 path.add_rounded_rectangle(rect, corner_radius);
-                if let Some(fill) = fill {
-                    fill_closed_path(&path.0, fill, options, out);
-                }
-                if let Some(line_style) = outline {
-                    paint_path_outline(&path.0, Closed, line_style, options, out);
-                }
+                fill_closed_path(&path.0, fill, options, out);
+                paint_path_outline(&path.0, Closed, outline, options, out);
             }
         }
         PaintCmd::Text {
@@ -666,6 +656,9 @@ pub fn tessellate_paint_command(
             text_style,
             color,
         } => {
+            if color == TRANSPARENT {
+                return;
+            }
             galley.sanity_check();
 
             let num_chars = galley.text.chars().count();
@@ -737,8 +730,8 @@ pub fn tessellate_paint_commands(
                 PaintCmd::Rect {
                     rect: *clip_rect,
                     corner_radius: 0.0,
-                    fill: None,
-                    outline: Some(LineStyle::new(2.0, srgba(150, 255, 150, 255))),
+                    fill: Default::default(),
+                    outline: LineStyle::new(2.0, srgba(150, 255, 150, 255)),
                 },
                 options,
                 fonts,

egui/src/painter.rs

@@ -131,8 +131,8 @@ impl Painter {
         self.add(PaintCmd::Rect {
             rect: rect.expand(2.0),
             corner_radius: 0.0,
-            fill: Some(Srgba::black_alpha(240)),
-            outline: Some(LineStyle::new(1.0, color::RED)),
+            fill: Srgba::black_alpha(240),
+            outline: LineStyle::new(1.0, color::RED),
         });
         self.galley(rect.min, galley, text_style, color::RED);
     }
@@ -151,8 +151,8 @@ impl Painter {
         self.add(PaintCmd::Circle {
             center,
             radius,
-            fill: Some(fill_color.into()),
-            outline: None,
+            fill: fill_color.into(),
+            outline: Default::default(),
         });
     }
 
@@ -160,8 +160,8 @@ impl Painter {
         self.add(PaintCmd::Circle {
             center,
             radius,
-            fill: None,
-            outline: Some(outline.into()),
+            fill: Default::default(),
+            outline: outline.into(),
         });
     }
 
@@ -169,8 +169,8 @@ impl Painter {
         self.add(PaintCmd::Rect {
             rect,
             corner_radius,
-            fill: Some(fill_color.into()),
-            outline: None,
+            fill: fill_color.into(),
+            outline: Default::default(),
         });
     }
 
@@ -178,8 +178,8 @@ impl Painter {
         self.add(PaintCmd::Rect {
             rect,
             corner_radius,
-            fill: None,
-            outline: Some(outline.into()),
+            fill: Default::default(),
+            outline: outline.into(),
         });
     }
 }

egui/src/style.rs

@@ -139,11 +139,11 @@ impl Interacted {
 #[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct WidgetVisuals {
     /// Background color of widget
-    pub bg_fill: Option<Srgba>,
+    pub bg_fill: Srgba,
 
     /// For surrounding rectangle of things that need it,
     /// like buttons, the box of the checkbox, etc.
-    pub bg_outline: Option<LineStyle>,
+    pub bg_outline: LineStyle,
 
     /// Button frames etc
     pub corner_radius: f32,
@@ -226,32 +226,32 @@ impl Default for Interacted {
     fn default() -> Self {
         Self {
             active: WidgetVisuals {
-                bg_fill: Some(Srgba::black_alpha(128)),
-                bg_outline: Some(LineStyle::new(2.0, WHITE)),
+                bg_fill: Srgba::black_alpha(128),
+                bg_outline: LineStyle::new(2.0, WHITE),
                 corner_radius: 0.0,
                 main_fill: srgba(120, 120, 200, 255),
                 stroke_color: WHITE,
                 stroke_width: 2.0,
             },
             hovered: WidgetVisuals {
-                bg_fill: None,
-                bg_outline: Some(LineStyle::new(1.0, WHITE)),
+                bg_fill: TRANSPARENT,
+                bg_outline: LineStyle::new(1.0, WHITE),
                 corner_radius: 2.0,
                 main_fill: srgba(100, 100, 150, 255),
                 stroke_color: Srgba::gray(240),
                 stroke_width: 1.5,
             },
             inactive: WidgetVisuals {
-                bg_fill: None,
-                bg_outline: Some(LineStyle::new(1.0, Srgba::gray(128))),
+                bg_fill: TRANSPARENT,
+                bg_outline: LineStyle::new(1.0, Srgba::gray(128)),
                 corner_radius: 4.0,
                 main_fill: srgba(60, 60, 80, 255),
                 stroke_color: Srgba::gray(200), // Mustn't look grayed out!
                 stroke_width: 1.0,
             },
             disabled: WidgetVisuals {
-                bg_fill: None,
-                bg_outline: Some(LineStyle::new(0.5, Srgba::gray(128))),
+                bg_fill: TRANSPARENT,
+                bg_outline: LineStyle::new(0.5, Srgba::gray(128)),
                 corner_radius: 4.0,
                 main_fill: srgba(50, 50, 50, 255),
                 stroke_color: Srgba::gray(128), // Should look grayed out
@@ -361,8 +361,8 @@ impl WidgetVisuals {
             stroke_width,
         } = self;
 
-        let _ = bg_fill; // ui_color(ui, bg_fill, "bg_fill"); // TODO
-        let _ = bg_outline; // bg_outline.ui(ui, "bg_outline");// TODO
+        ui_color(ui, bg_fill, "bg_fill");
+        bg_outline.ui(ui, "bg_outline");
         ui.add(Slider::f32(corner_radius, 0.0..=10.0).text("corner_radius"));
         ui_color(ui, main_fill, "main_fill");
         ui_color(ui, stroke_color, "stroke_color");
@@ -417,7 +417,7 @@ impl LineStyle {
         let Self { width, color } = self;
         ui.horizontal_centered(|ui| {
             ui.label(format!("{}: ", text));
-            ui.add(Slider::f32(width, 0.0..=10.0));
+            ui.add(Slider::f32(width, 0.0..=10.0).text("width"));
             ui_color(ui, color, "color");
         });
     }

egui/src/widgets.rs

@@ -233,7 +233,7 @@ impl Button {
             text: text.into(),
             text_color: None,
             text_style: TextStyle::Button,
-            fill: None,
+            fill: Default::default(),
             sense: Sense::click(),
         }
     }
@@ -289,11 +289,11 @@ impl Widget for Button {
         let rect = ui.allocate_space(size);
         let response = ui.interact(rect, id, sense);
         let text_cursor = response.rect.left_center() + vec2(padding.x, -0.5 * galley.size.y);
-        let bg_fill = fill.or(ui.style().interact(&response).bg_fill);
+        let fill = fill.unwrap_or(ui.style().interact(&response).bg_fill);
         ui.painter().add(PaintCmd::Rect {
             rect: response.rect,
             corner_radius: ui.style().interact(&response).corner_radius,
-            fill: bg_fill,
+            fill,
             outline: ui.style().interact(&response).bg_outline,
         });
         let stroke_color = ui.style().interact(&response).stroke_color;
@@ -372,8 +372,8 @@ impl<'a> Widget for Checkbox<'a> {
                     pos2(small_icon_rect.right(), small_icon_rect.top()),
                 ]),
                 closed: false,
-                outline: Some(LineStyle::new(ui.style().visuals.line_width, stroke_color)),
-                fill: None,
+                outline: LineStyle::new(ui.style().visuals.line_width, stroke_color),
+                fill: Default::default(),
             });
         }
 
@@ -448,8 +448,8 @@ impl Widget for RadioButton {
             painter.add(PaintCmd::Circle {
                 center: small_icon_rect.center(),
                 radius: small_icon_rect.width() / 3.0,
-                fill: Some(stroke_color),
-                outline: None,
+                fill: stroke_color,
+                outline: Default::default(),
             });
         }
 
@@ -515,10 +515,6 @@ impl Widget for Separator {
 
         let available_space = ui.available_finite().size();
 
-        // TODO: only allocate `spacing`, but not our full width/height
-        // as that would make the false impression that we *need* all that space,
-        // which would prevent regions from auto-shrinking
-
         let (points, rect) = match ui.layout().dir() {
             Direction::Horizontal => {
                 let rect = ui.allocate_space(vec2(spacing, available_space.y));

egui/src/widgets/slider.rs

@@ -164,18 +164,18 @@ impl<'a> Slider<'a> {
             ui.painter().add(PaintCmd::Rect {
                 rect: rail_rect,
                 corner_radius: rail_radius,
-                fill: Some(ui.style().visuals.background_fill),
-                outline: Some(LineStyle::new(1.0, Srgba::gray(200))), // TODO
+                fill: ui.style().visuals.background_fill,
+                outline: LineStyle::new(1.0, Srgba::gray(200)), // TODO
             });
 
             ui.painter().add(PaintCmd::Circle {
                 center: pos2(marker_center_x, rail_rect.center().y),
                 radius: handle_radius(rect),
-                fill: Some(ui.style().interact(response).main_fill),
-                outline: Some(LineStyle::new(
+                fill: ui.style().interact(response).main_fill,
+                outline: LineStyle::new(
                     ui.style().interact(response).stroke_width,
                     ui.style().interact(response).stroke_color,
-                )),
+                ),
             });
         }
     }

egui/src/widgets/text_edit.rs

@@ -183,7 +183,7 @@ impl<'t> Widget for TextEdit<'t> {
             painter.add(PaintCmd::Rect {
                 rect: bg_rect,
                 corner_radius: ui.style().interact(&response).corner_radius,
-                fill: Some(ui.style().visuals.dark_bg_color),
+                fill: ui.style().visuals.dark_bg_color,
                 outline: ui.style().interact(&response).bg_outline,
             });
         }