more dpi fixes:

- margin and padding
- Widget::draw_batch
- trip timeline
- custom buttons

and finally enable automatically setting DPI based on the monitor!!!
[rebuild]

ezgui/src/geom.rs

@@ -189,6 +189,14 @@ impl GeomBatch {
             self.fancy_push(color, poly.translate(dx, dy));
         }
     }
+
+    /// Scales the batch by some factor.
+    pub fn scale(mut self, factor: f64) -> GeomBatch {
+        for (_, poly) in &mut self.list {
+            *poly = poly.scale(factor);
+        }
+        self
+    }
 }
 
 pub enum RewriteColor {

ezgui/src/managed.rs

@@ -223,7 +223,12 @@ impl Widget {
     // TODO These are literally just convenient APIs to avoid importing JustDraw. Do we want this
     // or not?
     pub fn draw_batch(ctx: &EventCtx, batch: GeomBatch) -> Widget {
-        JustDraw::wrap(ctx, batch)
+        let scale = ctx.get_scale_factor();
+        if scale == 1.0 {
+            JustDraw::wrap(ctx, batch)
+        } else {
+            JustDraw::wrap(ctx, batch.scale(scale))
+        }
     }
     pub fn draw_svg<I: Into<String>>(ctx: &EventCtx, filename: I) -> Widget {
         JustDraw::svg(ctx, filename.into())
@@ -287,7 +292,13 @@ impl Widget {
     }
 
     // Populate a flattened list of Nodes, matching the traversal order
-    fn get_flexbox(&self, parent: Node, stretch: &mut Stretch, nodes: &mut Vec<Node>) {
+    fn get_flexbox(
+        &self,
+        parent: Node,
+        scale_factor: f32,
+        stretch: &mut Stretch,
+        nodes: &mut Vec<Node>,
+    ) {
         if let Some(container) = self.widget.downcast_ref::<Container>() {
             let mut style = self.layout.style.clone();
             style.flex_direction = if container.is_row {
@@ -298,7 +309,7 @@ impl Widget {
             let node = stretch.new_node(style, Vec::new()).unwrap();
             nodes.push(node);
             for widget in &container.members {
-                widget.get_flexbox(node, stretch, nodes);
+                widget.get_flexbox(node, scale_factor, stretch, nodes);
             }
             stretch.add_child(parent, node).unwrap();
             return;
@@ -308,6 +319,32 @@ impl Widget {
                 width: Dimension::Points(self.widget.get_dims().width as f32),
                 height: Dimension::Points(self.widget.get_dims().height as f32),
             };
+            if scale_factor != 1.0 {
+                if let Dimension::Points(ref mut px) = style.padding.start {
+                    *px *= scale_factor;
+                }
+                if let Dimension::Points(ref mut px) = style.padding.end {
+                    *px *= scale_factor;
+                }
+                if let Dimension::Points(ref mut px) = style.padding.top {
+                    *px *= scale_factor;
+                }
+                if let Dimension::Points(ref mut px) = style.padding.bottom {
+                    *px *= scale_factor;
+                }
+                if let Dimension::Points(ref mut px) = style.margin.start {
+                    *px *= scale_factor;
+                }
+                if let Dimension::Points(ref mut px) = style.margin.end {
+                    *px *= scale_factor;
+                }
+                if let Dimension::Points(ref mut px) = style.margin.top {
+                    *px *= scale_factor;
+                }
+                if let Dimension::Points(ref mut px) = style.margin.bottom {
+                    *px *= scale_factor;
+                }
+            }
             let node = stretch.new_node(style, Vec::new()).unwrap();
             stretch.add_child(parent, node).unwrap();
             nodes.push(node);
@@ -509,7 +546,12 @@ impl Composite {
             .unwrap();
 
         let mut nodes = vec![];
-        self.top_level.get_flexbox(root, &mut stretch, &mut nodes);
+        self.top_level.get_flexbox(
+            root,
+            ctx.get_scale_factor() as f32,
+            &mut stretch,
+            &mut nodes,
+        );
         nodes.reverse();
 
         // TODO Express more simply. Constraining this seems useless.

ezgui/src/runner.rs

@@ -164,7 +164,7 @@ pub struct Settings {
     profiling_enabled: bool,
     default_font_size: usize,
     dump_raw_events: bool,
-    scale_factor: f64,
+    scale_factor: Option<f64>,
     window_icon: Option<String>,
 }
 
@@ -176,7 +176,7 @@ impl Settings {
             profiling_enabled: false,
             default_font_size: text::DEFAULT_FONT_SIZE,
             dump_raw_events: false,
-            scale_factor: 1.0,
+            scale_factor: None,
             window_icon: None,
         }
     }
@@ -196,7 +196,7 @@ impl Settings {
     }
 
     pub fn scale_factor(&mut self, scale_factor: f64) {
-        self.scale_factor = scale_factor;
+        self.scale_factor = Some(scale_factor);
     }
 
     pub fn window_icon(&mut self, path: &str) {
@@ -224,7 +224,9 @@ pub fn run<G: 'static + GUI, F: FnOnce(&mut EventCtx) -> G>(settings: Settings,
         assets: Assets::new(
             settings.default_font_size,
             settings.font_dir,
-            settings.scale_factor,
+            settings
+                .scale_factor
+                .unwrap_or_else(|| prerender_innards.monitor_scale_factor()),
         ),
         num_uploads: Cell::new(0),
         inner: prerender_innards,

ezgui/src/widgets/button.rs

@@ -402,12 +402,12 @@ impl BtnBuilder {
             }
             BtnBuilder::Custom(normal, hovered, hitbox, maybe_t) => Button::new(
                 ctx,
-                normal,
-                hovered,
+                normal.scale(ctx.get_scale_factor()),
+                hovered.scale(ctx.get_scale_factor()),
                 key,
                 &action_tooltip.into(),
                 maybe_t,
-                hitbox,
+                hitbox.scale(ctx.get_scale_factor()),
             ),
         }
     }

game/src/info/trip.rs

@@ -423,7 +423,7 @@ fn make_timeline(
                 normal.add_svg(
                     ctx.prerender,
                     "../data/system/assets/timeline/current_pos.svg",
-                    Pt2D::new(p * phase_width, 7.5),
+                    Pt2D::new(p * phase_width, 7.5 * ctx.get_scale_factor()),
                     1.0,
                     Angle::ZERO,
                     RewriteColor::NoOp,
@@ -450,7 +450,7 @@ fn make_timeline(
                 TripPhaseType::Remote => "../data/system/assets/timeline/delayed_start.svg",
             },
             // TODO Hardcoded layouting...
-            Pt2D::new(0.5 * phase_width, -20.0),
+            Pt2D::new(0.5 * phase_width, -20.0 * ctx.get_scale_factor()),
             1.0,
             Angle::ZERO,
             RewriteColor::NoOp,