BGE bug #18883: Softbodies being hit by ghost objects. Added a one liner fix in Bullet. I will also report the fix to Erwin so that it can be added to next Bullet version.

1 files changed, 17 insertions, 15 deletions

diff --git a/extern/bullet2/src/BulletSoftBody/btSoftBody.cpp b/extern/bullet2/src/BulletSoftBody/btSoftBody.cpp
index a90acb99f04..0d19fd193e7 100644
--- a/extern/bullet2/src/BulletSoftBody/btSoftBody.cpp
+++ b/extern/bullet2/src/BulletSoftBody/btSoftBody.cpp
@@ -2780,21 +2780,23 @@ void btSoftBody::PSolve_RContacts(btSoftBody* psb, btScalar kst, btScalar ti)
 	{
 		const RContact&		c = psb->m_rcontacts[i];
 		const sCti&			cti = c.m_cti;	
-		btRigidBody* tmpRigid = btRigidBody::upcast(cti.m_colObj);
-
-		const btVector3		va = tmpRigid ? tmpRigid->getVelocityInLocalPoint(c.m_c1)*dt : btVector3(0,0,0);
-		const btVector3		vb = c.m_node->m_x-c.m_node->m_q;	
-		const btVector3		vr = vb-va;
-		const btScalar		dn = btDot(vr, cti.m_normal);		
-		if(dn<=SIMD_EPSILON)
-		{
-			const btScalar		dp = btMin( (btDot(c.m_node->m_x, cti.m_normal) + cti.m_offset), mrg );
-			const btVector3		fv = vr - (cti.m_normal * dn);
-			// c0 is the impulse matrix, c3 is 1 - the friction coefficient or 0, c4 is the contact hardness coefficient
-			const btVector3		impulse = c.m_c0 * ( (vr - (fv * c.m_c3) + (cti.m_normal * (dp * c.m_c4))) * kst );
-			c.m_node->m_x -= impulse * c.m_c2;
-			if (tmpRigid)
-				tmpRigid->applyImpulse(impulse,c.m_c1);
+
+		if (cti.m_colObj->hasContactResponse()) {
+			btRigidBody* tmpRigid = btRigidBody::upcast(cti.m_colObj);
+			const btVector3		va = tmpRigid ? tmpRigid->getVelocityInLocalPoint(c.m_c1)*dt : btVector3(0,0,0);
+			const btVector3		vb = c.m_node->m_x-c.m_node->m_q;	
+			const btVector3		vr = vb-va;
+			const btScalar		dn = btDot(vr, cti.m_normal);		
+			if(dn<=SIMD_EPSILON)
+			{
+				const btScalar		dp = btMin( (btDot(c.m_node->m_x, cti.m_normal) + cti.m_offset), mrg );
+				const btVector3		fv = vr - (cti.m_normal * dn);
+				// c0 is the impulse matrix, c3 is 1 - the friction coefficient or 0, c4 is the contact hardness coefficient
+				const btVector3		impulse = c.m_c0 * ( (vr - (fv * c.m_c3) + (cti.m_normal * (dp * c.m_c4))) * kst );
+				c.m_node->m_x -= impulse * c.m_c2;
+				if (tmpRigid)
+					tmpRigid->applyImpulse(impulse,c.m_c1);
+			}
 		}
 	}
 }