Bezier-rs: Add function to smoothly join bezier curves (#1037)

* Added bezier join

* Stylistic changes per review

website/other/bezier-rs-demos/src/features/bezier-features.ts

@@ -483,6 +483,56 @@ const bezierFeatures = {
 		},
 		chooseTVariant: true,
 	},
+	join: {
+		name: "Join",
+		callback: (bezier: WasmBezierInstance): string => {
+			const points = JSON.parse(bezier.get_points());
+			let examplePoints = [];
+			if (points.length === 2) {
+				examplePoints = [
+					[120, 155],
+					[40, 155],
+				];
+			} else if (points.length === 3) {
+				examplePoints = [
+					[40, 150],
+					[95, 195],
+					[155, 145],
+				];
+			} else {
+				examplePoints = [
+					[140, 150],
+					[85, 110],
+					[65, 180],
+					[30, 140],
+				];
+			}
+			return bezier.join(examplePoints);
+		},
+		demoOptions: {
+			Linear: {
+				customPoints: [
+					[45, 40],
+					[130, 90],
+				],
+			},
+			Quadratic: {
+				customPoints: [
+					[153, 40],
+					[40, 20],
+					[75, 85],
+				],
+			},
+			Cubic: {
+				customPoints: [
+					[20, 80],
+					[40, 20],
+					[90, 100],
+					[130, 55],
+				],
+			},
+		},
+	},
 };
 
 export type BezierFeatureKey = keyof typeof bezierFeatures;