Fix "panic" in BoolOps by introducing i_overlay

We've had several reports of crashes in our BooleanOps implementation
over the years. Some of them have been addressed, but there remains a
long tail of crashes.

FIXES #913, #948, #976, #1053, #1064, #1103, #1104, #1127, #1174, #1189, 1193

The root of the issue (as I understand it) is that floating point
rounding errors break the invariants of our sweep line algorithm. After
a couple years, it seems like a "simple" resolution is not in sight.

In the meanwhile, the i_overlay crate appeared. It uses a strategy that
maps floating point geometries to a scaled fixed point grid, which
nicely avoids the kind of problems we were having.

Related changes included:

Included are some tests that cover all reports in the issue tracker of the existing BoolOps panic'ing

JTS supports Bops between all geometry types. We support a more limited
set:

1. Two 2-Dimensional geometries `boolean_op`.
2. A 1-Dimenstinoal geometry with a 2-D geometry, which we call `clip`.

So this maps JTS's Line x Poly intersection tests to our Clip method.

- rm unused sweep code now that old boolops is gone

  I marked a couple fields as `allow(unused)` because they are used for
  printing debug repr in tests.

Speed up benches by only benching local boolop impl by default

geo-bool-ops-benches/Cargo.toml

@@ -5,6 +5,10 @@ edition = "2021"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
+[features]
+# If you want to bench against the `geo-booleanop` crate as a comparison, enable this feature.
+bench-foreign-booleanop = []
+
 [dependencies]
 geo = { path = "../geo" }
 geo-types = { path = "../geo-types" }

geo-bool-ops-benches/benches/boolean_ops.rs

@@ -1,12 +1,8 @@
 use std::f64::consts::PI;
 
 use criterion::{measurement::Measurement, *};
-use geo::{
-    algorithm::{BooleanOps, Rotate},
-    Relate,
-};
+use geo::algorithm::{BooleanOps, Rotate};
 
-use geo_booleanop::boolean::BooleanOp as OtherBooleanOp;
 use rand::{thread_rng, Rng};
 use rand_distr::Standard;
 
@@ -60,33 +56,39 @@ fn run_complex<T: Measurement>(c: &mut Criterion<T>) {
             );
         });
 
-        group.bench_with_input(
-            BenchmarkId::new("rgbops::intersection", steps),
-            &(),
-            |b, _| {
+        #[cfg(feature = "bench-foreign-booleanop")]
+        {
+            use geo::algorithm::Relate;
+            use geo_booleanop::boolean::BooleanOp as OtherBooleanOp;
+
+            group.bench_with_input(
+                BenchmarkId::new("rgbops::intersection", steps),
+                &(),
+                |b, _| {
+                    b.iter_batched(
+                        polys.sampler(),
+                        |(_, _, poly, poly2)| OtherBooleanOp::intersection(poly, poly2),
+                        BatchSize::SmallInput,
+                    );
+                },
+            );
+
+            group.bench_with_input(BenchmarkId::new("rgbops::union", steps), &(), |b, _| {
                 b.iter_batched(
                     polys.sampler(),
-                    |(_, _, poly, poly2)| OtherBooleanOp::intersection(poly, poly2),
+                    |(_, _, poly, poly2)| OtherBooleanOp::union(poly, poly2),
                     BatchSize::SmallInput,
                 );
-            },
-        );
+            });
 
-        group.bench_with_input(BenchmarkId::new("rgbops::union", steps), &(), |b, _| {
-            b.iter_batched(
-                polys.sampler(),
-                |(_, _, poly, poly2)| OtherBooleanOp::union(poly, poly2),
-                BatchSize::SmallInput,
-            );
-        });
-
-        group.bench_with_input(BenchmarkId::new("geo::relate", steps), &(), |b, _| {
-            b.iter_batched(
-                polys.sampler(),
-                |(poly, poly2, _, _)| poly.relate(poly2).is_intersects(),
-                BatchSize::SmallInput,
-            );
-        });
+            group.bench_with_input(BenchmarkId::new("geo::relate", steps), &(), |b, _| {
+                b.iter_batched(
+                    polys.sampler(),
+                    |(poly, poly2, _, _)| poly.relate(poly2).is_intersects(),
+                    BatchSize::SmallInput,
+                );
+            });
+        }
     });
 }
 

geo/CHANGES.md

@@ -127,6 +127,8 @@
   * <https://github.com/georust/geo/pull/1148>
 * Point in `Triangle` and `Rect` performance improvemnets
   * <https://github.com/georust/geo/pull/1057>
+* Fix crashes in `BooleanOps`
+  * <https://github.com/georust/geo/pull/1234>
 
 ## 0.27.0
 

geo/Cargo.toml

@@ -30,6 +30,7 @@ proj = { version = "0.27.0", optional = true }
 robust = "1.1.0"
 rstar = "0.12.0"
 serde = { version = "1.0", optional = true, features = ["derive"] }
+i_overlay = "1.7.2"
 
 [dev-dependencies]
 approx = ">= 0.4.0, < 0.6.0"