diff --git a/src/bin/flat.rs b/src/bin/flat.rs
index 2fc69a9..36149e7 100644
--- a/src/bin/flat.rs
+++ b/src/bin/flat.rs
@@ -20,25 +20,7 @@ pub fn main() {
 		let canvas = create_drawing_window("Refraction");
 		canvas.draw(|gc| {
 			gc.canvas_height(1000.0);
-
-			gc.new_path();
-			//gc.circle(0.0, 0.0, space.coil_r + space.coil_w + space.coil_m);
-			//gc.circle(0.0, 0.0, space.coil_r + space.coil_w);
-			//gc.circle(0.0, 0.0, space.coil_r - space.coil_w);
-			//gc.circle(0.0, 0.0, space.coil_r - space.coil_w - space.coil_m);
-			gc.winding_rule(WindingRule::EvenOdd);
-			gc.fill_color(Color::Rgba(0.8, 0.8, 0.8, 1.0));
-			gc.fill();
-
-			gc.line_width(0.5);
-			gc.stroke_color(Color::Rgba(1.0, 0.5, 0.0, 1.0));
-			for y in itertools_num::linspace(-1.0, 1.0, 101) {
-				draw_ray(gc, &space, vec2(-500.0, 0.0), vec2(1.0, y));
-			}
-			// gc.stroke_color(Color::Rgba(0.0, 0.5, 1.0, 1.0));
-			// for y in itertools_num::linspace(-1.0, 1.0, 101) {
-			// 	draw_ray(gc, &space, vec2(0.0, space.coil_r), vec2(1.0, y));
-			// }
+			space.render(gc);
 		});
 	});
 }
@@ -56,6 +38,52 @@ fn draw_ray(gc: &mut Vec<Draw>, space: &impl Metric, base: Vec2, dir: Vec2) {
 	gc.stroke();
 }
 
+fn draw_fan(gc: &mut Vec<Draw>, space: &impl Metric, base: Vec2, dir: Vec2, spread: f32) {
+	let dir = dir.normalize();
+	let v = vec2(-dir.y, dir.x);
+	for y in itertools_num::linspace(-spread, spread, 101) {
+		draw_ray(gc, space, base, dir + y * v);
+	}
+}
+
+trait Renderable {
+	fn render(&self, gc: &mut Vec<Draw>);
+}
+
+impl Renderable for Coil {
+	fn render(&self, gc: &mut Vec<Draw>) {
+		gc.new_path();
+		gc.circle(0.0, 0.0, self.coil_r + self.coil_w + self.coil_m);
+		gc.circle(0.0, 0.0, self.coil_r + self.coil_w);
+		gc.circle(0.0, 0.0, self.coil_r - self.coil_w);
+		gc.circle(0.0, 0.0, self.coil_r - self.coil_w - self.coil_m);
+		gc.winding_rule(WindingRule::EvenOdd);
+		gc.fill_color(Color::Rgba(0.8, 0.8, 0.8, 1.0));
+		gc.fill();
+		gc.line_width(0.5);
+		gc.stroke_color(Color::Rgba(1.0, 0.5, 0.0, 1.0));
+		draw_fan(gc, self, vec2(-500.0, 0.0), vec2(1.0, 0.0), 1.0);
+		gc.stroke_color(Color::Rgba(0.0, 0.5, 1.0, 1.0));
+		draw_fan(gc, self, vec2(0.0, self.coil_r), vec2(1.0, 0.0), 1.0);
+	}
+}
+
+impl Renderable for Rect {
+	fn render(&self, gc: &mut Vec<Draw>) {
+		gc.new_path();
+		gc.rect(self.box_a.x - self.box_m.x, self.box_a.y - self.box_m.y, self.box_b.x + self.box_m.x, self.box_b.y + self.box_m.y);
+		gc.rect(self.box_a.x, self.box_a.y, self.box_b.x, self.box_b.y);
+		gc.winding_rule(WindingRule::EvenOdd);
+		gc.fill_color(Color::Rgba(0.8, 0.8, 0.8, 1.0));
+		gc.fill();
+		gc.line_width(0.5);
+		gc.stroke_color(Color::Rgba(1.0, 0.5, 0.0, 1.0));
+		draw_fan(gc, self, vec2(-500.0, 0.0), vec2(1.0, 0.0), 1.0);
+		gc.stroke_color(Color::Rgba(0.0, 0.5, 1.0, 1.0));
+		draw_fan(gc, self, vec2(0.0, 0.5 * self.box_a.y), vec2(1.0, 1.0), 1.0);
+	}
+}
+
 struct Coil {
 	coil_m: f32,
 	coil_scale: f32,