Outsource the contact manifold, SAT, and some shapes.

benchmarks3d/trimesh3.rs

@@ -1,6 +1,6 @@
-use na::Point3;
+use na::{ComplexField, DMatrix, Point3, Vector3};
 use rapier3d::dynamics::{JointSet, RigidBodyBuilder, RigidBodySet};
-use rapier3d::geometry::{ColliderBuilder, ColliderSet};
+use rapier3d::geometry::{ColliderBuilder, ColliderSet, HeightField};
 use rapier_testbed3d::Testbed;
 
 pub fn init_world(testbed: &mut Testbed) {
@@ -14,28 +14,27 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Ground
      */
-    let ground_size = 200.0f32;
-    let ground_height = 1.0;
+    let ground_size = Vector3::new(200.0, 1.0, 200.0);
     let nsubdivs = 20;
 
-    let quad = rapier3d::ncollide::procedural::quad(ground_size, ground_size, nsubdivs, nsubdivs);
-    let indices = quad
-        .flat_indices()
-        .chunks(3)
-        .map(|is| Point3::new(is[0], is[2], is[1]))
-        .collect();
-    let mut vertices = quad.coords;
+    let heights = DMatrix::from_fn(nsubdivs + 1, nsubdivs + 1, |i, j| {
+        if i == 0 || i == nsubdivs || j == 0 || j == nsubdivs {
+            10.0
+        } else {
+            let x = i as f32 * ground_size.x / (nsubdivs as f32);
+            let z = j as f32 * ground_size.z / (nsubdivs as f32);
 
-    // ncollide generates a quad with `z` as the normal.
-    // so we switch z and y here and set a random altitude at each point.
-    for p in vertices.iter_mut() {
-        p.z = p.y;
-        p.y = (p.x.sin() + p.z.cos()) * ground_height;
-
-        if p.x.abs() == ground_size / 2.0 || p.z.abs() == ground_size / 2.0 {
-            p.y = 10.0;
+            // NOTE: make sure we use the sin/cos from simba to ensure
+            // cross-platform determinism of the example when the
+            // enhanced_determinism feature is enabled.
+            <f32 as ComplexField>::sin(x) + <f32 as ComplexField>::cos(z)
         }
-    }
+    });
+
+    // Here we will build our trimesh from the mesh representation of an
+    // heightfield.
+    let heightfield = HeightField::new(heights, ground_size);
+    let (vertices, indices) = heightfield.to_trimesh();
 
     let rigid_body = RigidBodyBuilder::new_static().build();
     let handle = bodies.insert(rigid_body);