feat: expose clipper builder, add path methods

* Exposes the Clipper builder struct that uses a
  type state API to allow boolean operations on
  multiple paths at once.
* Create Clipper builders from Paths::to_clipper_subject() and
  Paths::to_clipper_open_subject().
* Add inflate/simplify methods to Path and Paths
* Update documentation and examples

README.md

@@ -28,7 +28,7 @@ mod helpers;
 #[macroquad::main("Difference and inflate")]
 async fn main() {
     let circle = circle_path((5.0, 5.0), 3.0, 32);
-    let rectangle: Paths = vec![(0.0, 0.0), (5.0, 0.0), (5.0, 6.0), (0.0, 6.0)].into();
+    let rectangle = vec![(0.0, 0.0), (5.0, 0.0), (5.0, 6.0), (0.0, 6.0)];
     let circle2 = circle_path((7.0, 7.0), 1.0, 32);
 
     let result = difference(circle, rectangle, FillRule::default())

examples/difference-and-inflate.rs

@@ -5,18 +5,31 @@ use macroquad::prelude::*;
 mod helpers;
 
 #[macroquad::main("Difference and inflate")]
-async fn main() {
+async fn main() -> Result<(), ClipperError> {
     let circle = circle_path((5.0, 5.0), 3.0, 32);
-    let rectangle: Paths = vec![(0.0, 0.0), (5.0, 0.0), (5.0, 6.0), (0.0, 6.0)].into();
-    let circle2 = circle_path((7.0, 7.0), 1.0, 32);
+    let circle2 = circle_path((6.0, 6.0), 2.0, 32);
+    let circle3 = circle_path((7.0, 7.0), 1.0, 32);
+    let rectangle = vec![(0.0, 0.0), (5.0, 0.0), (5.0, 6.0), (0.0, 6.0)];
 
-    let result = difference(circle, rectangle, FillRule::default())
-        .expect("Failed to run boolean operation");
+    // Functional API
+    let _result = difference(circle.clone(), circle2.clone(), FillRule::default())?;
+    let _result = difference(_result, circle3.clone(), FillRule::default())?;
+    let _result = difference(_result, rectangle.clone(), FillRule::default())?;
 
-    let result = difference(result.clone(), circle2, FillRule::default())
-        .expect("Failed to run boolean operation");
+    let _result2 = inflate(_result, 1.0, JoinType::Round, EndType::Polygon, 0.0);
+    let _result2 = simplify(_result2, 0.01, false);
 
-    let result2 = inflate(result.clone(), 1.0, JoinType::Round, EndType::Polygon, 0.0);
+    // Alternative Clipper builder API
+    let result = circle
+        .to_clipper_subject()
+        .add_clip(circle2)
+        .add_clip(circle3)
+        .add_clip(rectangle)
+        .difference(FillRule::default())?;
+
+    let result2 = result
+        .inflate(1.0, JoinType::Round, EndType::Polygon, 0.0)
+        .simplify(0.01, false);
 
     loop {
         clear_background(BLACK);

examples/difference.rs

@@ -5,12 +5,18 @@ use macroquad::prelude::*;
 mod helpers;
 
 #[macroquad::main("Difference")]
-async fn main() {
+async fn main() -> Result<(), ClipperError> {
     let path_a: Paths = vec![(0.2, 0.2), (6.0, 0.2), (6.0, 6.0), (0.2, 6.0)].into();
     let path_b: Paths = vec![(5.0, 5.0), (8.0, 5.0), (8.0, 8.0), (5.0, 8.0)].into();
 
-    let result = difference(path_a.clone(), path_b.clone(), FillRule::default())
-        .expect("Failed to run boolean operation");
+    // Functional API
+    let _result = difference(path_a.clone(), path_b.clone(), FillRule::default())?;
+
+    // Alternative Clipper builder API
+    let result = path_a
+        .to_clipper_subject()
+        .add_clip(path_b.clone())
+        .difference(FillRule::default())?;
 
     loop {
         clear_background(BLACK);

examples/inflate.rs

@@ -8,7 +8,11 @@ mod helpers;
 async fn main() {
     let path: Paths = vec![(2.0, 2.0), (6.0, 2.0), (6.0, 10.0), (2.0, 6.0)].into();
 
-    let result = inflate(path.clone(), 1.0, JoinType::Round, EndType::Polygon, 0.0);
+    // Functional API
+    let _result = inflate(path.clone(), 1.0, JoinType::Round, EndType::Polygon, 0.0);
+
+    // Alternative paths API
+    let result = path.inflate(1.0, JoinType::Round, EndType::Polygon, 0.0);
 
     loop {
         clear_background(BLACK);

examples/intersect.rs

@@ -5,12 +5,18 @@ use macroquad::prelude::*;
 mod helpers;
 
 #[macroquad::main("Intersect")]
-async fn main() {
+async fn main() -> Result<(), ClipperError> {
     let path_a: Paths = vec![(0.2, 0.2), (6.0, 0.2), (6.0, 6.0), (0.2, 6.0)].into();
     let path_b: Paths = vec![(5.0, 5.0), (8.0, 5.0), (8.0, 8.0), (5.0, 8.0)].into();
 
-    let result = intersect::<Centi>(path_a.clone(), path_b.clone(), FillRule::default())
-        .expect("Failed to run boolean operation");
+    // Functional API
+    let _result = intersect::<Centi>(path_a.clone(), path_b.clone(), FillRule::default())?;
+
+    // Alternative Clipper builder API
+    let result = path_a
+        .to_clipper_subject()
+        .add_clip(path_b.clone())
+        .intersect(FillRule::default())?;
 
     loop {
         clear_background(BLACK);

examples/simplify.rs

@@ -1,20 +1,26 @@
 use clipper2::*;
-use helpers::{draw_paths, draw_paths_points};
+use helpers::{draw_path, draw_path_points};
 use macroquad::prelude::*;
 
 mod helpers;
 
 #[macroquad::main("Simplify")]
 async fn main() {
-    let path: Paths = vec![(1.0, 2.0), (1.0, 2.5), (1.2, 4.0), (1.8, 6.0)].into();
-    let path_simplified = simplify(path.translate(3.0, 0.0), 0.5, false);
+    let path: Path = vec![(1.0, 2.0), (1.0, 2.5), (1.2, 4.0), (1.8, 6.0)].into();
+
+    // Functional API
+    let _path = path.translate(3.0, 3.0);
+    let _simplified = simplify(path.clone(), 0.5, false);
+
+    // Alternative paths API
+    let simplified = path.translate(3.0, 0.0).simplify(0.5, false);
 
     loop {
         clear_background(BLACK);
-        draw_paths(&path, SKYBLUE);
-        draw_paths(&path_simplified, SKYBLUE);
-        draw_paths_points(&path, GREEN);
-        draw_paths_points(&path_simplified, GREEN);
+        draw_path(&path, SKYBLUE);
+        draw_path(&simplified, SKYBLUE);
+        draw_path_points(&path, GREEN);
+        draw_path_points(&simplified, GREEN);
         next_frame().await
     }
 }

examples/union.rs

@@ -5,12 +5,18 @@ use macroquad::prelude::*;
 mod helpers;
 
 #[macroquad::main("Union")]
-async fn main() {
+async fn main() -> Result<(), ClipperError> {
     let path_a: Paths = vec![(0.2, 0.2), (6.0, 0.2), (6.0, 6.0), (0.2, 6.0)].into();
     let path_b: Paths = vec![(5.0, 5.0), (8.0, 5.0), (8.0, 8.0), (5.0, 8.0)].into();
 
-    let result = union(path_a.clone(), path_b.clone(), FillRule::default())
-        .expect("Failed to run boolean operation");
+    // Functional API
+    let _result = union(path_a.clone(), path_b.clone(), FillRule::default())?;
+
+    // Alternative Clipper builder API
+    let result = path_a
+        .to_clipper_subject()
+        .add_clip(path_b.clone())
+        .union(FillRule::default())?;
 
     loop {
         clear_background(BLACK);

examples/xor.rs

@@ -5,12 +5,18 @@ use macroquad::prelude::*;
 mod helpers;
 
 #[macroquad::main("XOR")]
-async fn main() {
+async fn main() -> Result<(), ClipperError> {
     let path_a: Paths = vec![(0.2, 0.2), (6.0, 0.2), (6.0, 6.0), (0.2, 6.0)].into();
     let path_b: Paths = vec![(5.0, 5.0), (8.0, 5.0), (8.0, 8.0), (5.0, 8.0)].into();
 
-    let result = xor(path_a.clone(), path_b.clone(), FillRule::default())
-        .expect("Failed to run boolean operation");
+    // Functional API
+    let _result = xor(path_a.clone(), path_b.clone(), FillRule::default())?;
+
+    // Alternative Clipper builder API
+    let result = path_a
+        .to_clipper_subject()
+        .add_clip(path_b.clone())
+        .xor(FillRule::default())?;
 
     loop {
         clear_background(BLACK);