From 459d07a302cae23febd752b4b2b1d0b2f28143ca Mon Sep 17 00:00:00 2001
From: erwincoumans <erwin.coumans@gmail.com>
Date: Tue, 12 Jun 2018 16:10:49 -0700
Subject: [PATCH] add example for enableSAT, using separating axis test
 (instead of GJK) for contact between polyhedral convex hull shapes (and
 convex hull vs triangle in a concave triangle mesh)

---
 data/cube_concave.urdf                     | 32 ++++++++++++++++++++++
 examples/pybullet/examples/satCollision.py | 14 ++++++++++
 2 files changed, 46 insertions(+)
 create mode 100644 data/cube_concave.urdf
 create mode 100644 examples/pybullet/examples/satCollision.py

diff --git a/data/cube_concave.urdf b/data/cube_concave.urdf
new file mode 100644
index 000000000..0124c5ab1
--- /dev/null
+++ b/data/cube_concave.urdf
@@ -0,0 +1,32 @@
+<?xml version="0.0" ?>
+<robot name="cube">
+  <link name="baseLink">
+    <contact>
+      <lateral_friction value="1.0"/>
+      <rolling_friction value="0.0"/>
+      <contact_cfm value="0.0"/>
+      <contact_erp value="1.0"/>
+    </contact>
+    <inertial>
+      <origin rpy="0 0 0" xyz="0 0 0"/>
+       <mass value="1.0"/>
+       <inertia ixx="1" ixy="0" ixz="0" iyy="1" iyz="0" izz="1"/>
+    </inertial>
+    <visual>
+      <origin rpy="0 0 0" xyz="0 0 0"/>
+      <geometry>
+				<mesh filename="cube.obj" scale="1 1 1"/>
+      </geometry>
+       <material name="white">
+        <color rgba="1 1 1 1"/>
+      </material>
+    </visual>
+    <collision concave="yes">
+      <origin rpy="0 0 0" xyz="0 0 0"/>
+      <geometry>
+	 			<mesh filename="cube.obj" scale="1 1 1"/>
+      </geometry>
+    </collision>
+  </link>
+</robot>
+
diff --git a/examples/pybullet/examples/satCollision.py b/examples/pybullet/examples/satCollision.py
new file mode 100644
index 000000000..84111bf6c
--- /dev/null
+++ b/examples/pybullet/examples/satCollision.py
@@ -0,0 +1,14 @@
+import pybullet as p
+import time 
+
+p.connect(p.GUI)
+p.setGravity(0,0,-10)
+p.setPhysicsEngineParameter(enableSAT=1)
+p.loadURDF("cube_concave.urdf",[0,0,-25], globalScaling=50, useFixedBase=True)
+p.loadURDF("cube.urdf",[0,0,1], globalScaling=1)
+p.loadURDF("duck_vhacd.urdf",[1,0,1], globalScaling=1)
+
+while (p.isConnected()):
+	p.stepSimulation()
+	time.sleep(1./240.)
+	
\ No newline at end of file