From f06cd56f1317f4d1be33a6eae70ecc88a422d0e3 Mon Sep 17 00:00:00 2001
From: dajiaohuang <mikewushuwen@outlook.com>
Date: Fri, 16 Oct 2026 19:33:52 +0800
Subject: [PATCH] fix(gjk): scale shape-cast convergence tolerance

---
 crates/parry3d-f64/tests/shape_cast.rs | 28 ++++++++++++++++++++++++++
 src/query/gjk/gjk.rs                   |  6 +++++-
 2 files changed, 33 insertions(+), 1 deletion(-)
 create mode 100644 crates/parry3d-f64/tests/shape_cast.rs

diff --git a/crates/parry3d-f64/tests/shape_cast.rs b/crates/parry3d-f64/tests/shape_cast.rs
new file mode 100644
index 00000000..b4578180
--- /dev/null
+++ b/crates/parry3d-f64/tests/shape_cast.rs
@@ -0,0 +1,28 @@
+use parry3d_f64::math::{Pose, Vector};
+use parry3d_f64::query::{cast_shapes, ShapeCastOptions};
+use parry3d_f64::shape::Cuboid;
+
+#[test]
+fn cast_starting_at_touching_boundary_and_moving_inward_hits() {
+    let floor = Cuboid::new(Vector::new(38.0, 0.5, 4.0));
+    let floor_pos = Pose::from_translation(Vector::new(42.0, -0.5, 2.0));
+    let boxy = Cuboid::new(Vector::splat(0.25));
+    let options = ShapeCastOptions {
+        max_time_of_impact: 6.54806820868758261e-3,
+        target_distance: 0.01,
+        stop_at_penetration: false,
+        compute_impact_geometry_on_penetration: true,
+    };
+    let start = Vector::new(
+        f64::from_bits(0x4038019999998b41),
+        f64::from_bits(0x3fd0a3d70a3d7099),
+        f64::from_bits(0xbe095faa25f26d8d),
+    );
+    let dir = Vector::new(9.54479978035029708e-1, -2.98274993135946798e-1, 0.0);
+
+    for dy in [0.0, -1e-9, 1e-9] {
+        let pos = Pose::from_translation(start + Vector::Y * dy);
+        let hit = cast_shapes(&floor_pos, Vector::ZERO, &floor, &pos, dir, &boxy, options).unwrap();
+        assert!(hit.is_some(), "cast missed with start offset {dy}");
+    }
+}
diff --git a/src/query/gjk/gjk.rs b/src/query/gjk/gjk.rs
index 56f4caea..1f68e851 100644
--- a/src/query/gjk/gjk.rs
+++ b/src/query/gjk/gjk.rs
@@ -741,7 +741,11 @@ where
 
         let neg_proj_coords = -proj;
         let (normalized, dist) = neg_proj_coords.normalize_and_length();
-        if dist > _eps_tol {
+        let mut support_scale: Real = 1.0;
+        for i in 0..=simplex.dimension() {
+            support_scale = support_scale.max((simplex.point(i).point + curr_ray.origin).length());
+        }
+        if dist > _eps_tol * support_scale {
             dir = normalized;
             max_bound = dist;
         } else {