chore: rework vertical stacks demo

benchmarks2d/all_benchmarks2.rs

@@ -58,7 +58,7 @@ pub fn main() {
         ("Convex polygons", convex_polygons2::init_world),
         ("Heightfield", heightfield2::init_world),
         ("Pyramid", pyramid2::init_world),
-        ("Verticals tacks", vertical_stacks2::init_world),
+        ("Verticals stacks", vertical_stacks2::init_world),
         ("(Stress test) joint ball", joint_ball2::init_world),
         ("(Stress test) joint fixed", joint_fixed2::init_world),
         (

benchmarks2d/vertical_stacks2.rs

@@ -10,10 +10,14 @@ pub fn init_world(testbed: &mut Testbed) {
     let impulse_joints = ImpulseJointSet::new();
     let multibody_joints = MultibodyJointSet::new();
 
+
+    let num = 40;
+    let rad = 50.0 / 2.0; // 0.5;
+
     /*
      * Ground
      */
-    let ground_size = 100.0;
+    let ground_size = num as f32 * rad * 10.0;
     let ground_thickness = 1.0;
 
     let rigid_body = RigidBodyBuilder::fixed();
@@ -24,18 +28,22 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Create the cubes
      */
-    let num = 30;
-    let rad = 0.5;
 
-    let shift = rad * 2.0;
-    let centery = shift / 2.0 + ground_thickness;
+    let shiftx_centerx = [
+        (rad * 2.0, -(num as f32) * rad * 2.0 * 1.5),
+         (rad * 2.0 + rad, num as f32 * rad * 2.0 * 1.5),
+    ];
+
+    for (shiftx, centerx) in shiftx_centerx {
+        let shifty = rad * 2.0;
+        let centery = shifty / 2.0 + ground_thickness;
 
         for i in 0..num {
             for j in 0usize..1 + i * 2 {
                 let fj = j as f32;
                 let fi = i as f32;
-            let x = (fj - fi) * shift; // (shift + rad / 2.0);
-            let y = (num as f32 - fi - 1.0) * shift + centery;
+                let x = (fj - fi) * shiftx + centerx;
+                let y = (num as f32 - fi - 1.0) * shifty + centery;
 
                 // Build the rigid body.
                 let rigid_body = RigidBodyBuilder::dynamic().translation(vector![x, y]);
@@ -44,6 +52,7 @@ pub fn init_world(testbed: &mut Testbed) {
                 colliders.insert_with_parent(collider, handle, &mut bodies);
             }
         }
+    }
 
     /*
      * Set up the testbed.

src/dynamics/integration_parameters.rs

@@ -1,6 +1,8 @@
 use crate::math::Real;
 use std::num::NonZeroUsize;
 
+// TODO: enabling the block solver in 3d introduces a lot of jitters in
+//       the 3D domino demo. So for now we dont enable it in 3D.
 pub(crate) static BLOCK_SOLVER_ENABLED: bool = cfg!(feature = "dim2");
 pub(crate) static DISABLE_FRICTION_LIMIT_REAPPLY: bool = false;