public unsafe bool ConfigureContactManifold <TManifold>(int workerIndex, CollidablePair pair, ref TManifold manifold, out PairMaterialProperties pairMaterial) where TManifold : struct, IContactManifold <TManifold>
 {
     pairMaterial = new PairMaterialProperties {
         FrictionCoefficient = 1, MaximumRecoveryVelocity = 2, SpringSettings = new SpringSettings(30, 1)
     };
     Characters.TryReportContacts(pair, ref manifold, workerIndex, ref pairMaterial);
     return(true);
 }
 public unsafe bool ConfigureContactManifold(int workerIndex, CollidablePair pair, ConvexContactManifold *manifold, out PairMaterialProperties pairMaterial)
 {
     GetMaterial(out pairMaterial);
     Characters.TryReportContacts(pair, ref *manifold, workerIndex, ref pairMaterial);
     return(true);
 }