Provided bullet physics collision callback methods.

3 files changed, 71 insertions, 1 deletions

diff --git a/src/core/entity.cc b/src/core/entity.cc
index 1b879f3..46bcd5d 100644
--- a/src/core/entity.cc
+++ b/src/core/entity.cc
@@ -646,6 +646,7 @@ void Entity::reset()
 		//entity_body->setActivationState(ISLAND_SLEEPING);
 		entity_body->setActivationState(WANTS_DEACTIVATION);
 		entity_body->setCollisionFlags(entity_body->getCollisionFlags() | btCollisionObject::CF_STATIC_OBJECT);
+		entity_body->setUserPointer((void *) this);
 		
 		if (zone())
 			zone()->physics()->addRigidBody(entity_body);
@@ -779,6 +780,10 @@ void EntityDynamic::reset()
 		// create physics body
 		entity_body_info = new btRigidBody::btRigidBodyConstructionInfo(entity_mass, entity_motionstate, entity_collision_shape, inertia);	
 		entity_body = new btRigidBody(*entity_body_info);
+		// point the bullet user pointer to the entity
+		entity_body->setUserPointer((void *) this);
+		// enable custom collision callback
+		entity_body->setCollisionFlags(entity_body->getCollisionFlags() | btCollisionObject::CF_CUSTOM_MATERIAL_CALLBACK); 
 		
 		if (entity_mass) {
 			entity_body->setActivationState(DISABLE_DEACTIVATION);
@@ -800,6 +805,9 @@ void EntityDynamic::reset()
 		motionstate()->setWorldTransform(t);
 	}
 
+	/* Does not work
+	
+	
 	if (entity_mass) {
 		if (entity_state == Docked) {
 			entity_body->setActivationState(DISABLE_SIMULATION);
@@ -809,6 +817,7 @@ void EntityDynamic::reset()
 			entity_body->setActivationState(DISABLE_DEACTIVATION);
 		}
 	}
+	*/
 	
 	set_dirty();
 }
@@ -845,6 +854,10 @@ void EntityDynamic::frame(const unsigned long elapsed)
 	}
 }
 
+void EntityDynamic::collision(Entity *other)
+{
+}
+
 void EntityDynamic::serialize_server_create(std::ostream & os) const
 {
 	Entity::serialize_server_create(os);
@@ -1253,6 +1266,11 @@ void EntityControlable::reset()
 		entity_body_info = new btRigidBody::btRigidBodyConstructionInfo(entity_mass, entity_motionstate, entity_collision_shape, inertia);		
 		entity_body = new btRigidBody(*entity_body_info);
 		entity_body->setActivationState(DISABLE_DEACTIVATION);
+		// point the bullet user pointer to the entity
+		entity_body->setUserPointer((void *) this);
+		// enable custom collision callback
+		entity_body->setCollisionFlags(entity_body->getCollisionFlags() | btCollisionObject::CF_CUSTOM_MATERIAL_CALLBACK); 
+		
 		//entity_body->setCollisionFlags(entity_body->getCollisionFlags() | btCollisionObject::CF_KINEMATIC_OBJECT); 
 		
 		entity_actioninterface = new ActionInterface(this);
@@ -1269,6 +1287,8 @@ void EntityControlable::reset()
 	body()->setWorldTransform(t);
 	motionstate()->setWorldTransform(t);
 
+	/* Does not work
+	 
 	if (entity_state == Docked) {
 		entity_body->setActivationState(DISABLE_SIMULATION);
 		entity_body->setCollisionFlags(entity_body->getCollisionFlags() | btCollisionObject::CF_NO_CONTACT_RESPONSE);
@@ -1276,7 +1296,7 @@ void EntityControlable::reset()
 		entity_body->setActivationState(DISABLE_DEACTIVATION);
 		entity_body->setCollisionFlags(entity_body->getCollisionFlags() & ~btCollisionObject::CF_NO_CONTACT_RESPONSE);
 	}
-
+	*/
 	set_dirty();
 }
 
diff --git a/src/core/entity.h b/src/core/entity.h
index 19e47bc..092f4a7 100644
--- a/src/core/entity.h
+++ b/src/core/entity.h
@@ -630,6 +630,16 @@ public:
 	 * @brief reset the physics state
 	 */
 	virtual void reset();
+	
+	/**
+	 * @brief physics collision callback
+	 * This funcion is called by the physics engine if the entity collides with another entity.
+	 * It can be implemented by game child classes to provide collision effects and feedback.
+	 * If the collision happens between two EntityDynamic instances (or subclasses thereof)
+	 * the method will be called on each collision partner.
+	 * Warning: this can be called multiple times for a single collision
+	 * */
+	virtual void collision(Entity *other);
 
 protected:
 	float			entity_mass;
diff --git a/src/core/physics.cc b/src/core/physics.cc
index 9ffe13c..2c7dd96 100644
--- a/src/core/physics.cc
+++ b/src/core/physics.cc
@@ -8,10 +8,47 @@
 #include "core/physics.h"
 #include "core/zone.h"
 
+#include "btBulletDynamicsCommon.h"
 #include "BulletCollision/Gimpact/btGImpactCollisionAlgorithm.h"
 
 namespace core {
 
+/* ---- Bullet collision callbacks --------------------------------- */
+
+//extern ContactAddedCallback              gContactAddedCallback;
+
+/*
+ * 	see http://bulletphysics.org/mediawiki-1.5.8/index.php/Collision_Callbacks_and_Triggers
+ */
+
+bool bullet_contact_added_callback(btManifoldPoint &cp, const btCollisionObject *body0, int partId0, int index0, const btCollisionObject *body1, int partId1, int index1)
+{
+	Entity *entity0 = static_cast<Entity *>(body0->getUserPointer());
+	Entity *entity1 = static_cast<Entity *>(body1->getUserPointer());
+	
+	assert(entity0 && entity1);
+	
+	// FIXME there should probably be an entity flag indiciating wether or not it has a collision callback
+	
+	if ((entity0->type() == Entity::Dynamic) || (entity0->type() == Entity::Controlable)) {
+		static_cast<EntityDynamic *>(entity0)->collision(entity1);
+	}
+	
+	if ((entity1->type() == Entity::Dynamic) || (entity1->type() == Entity::Controlable)) {
+		static_cast<EntityDynamic *>(entity1)->collision(entity0);
+	}
+	//con_debug << "collision " << entity0->label() << " - " << entity1->label() << std::endl;
+	
+	// the return value should be ignored by bullet.
+	return true;
+}
+
+//bool bullet_contact_processed_callback(btManifoldPoint& cp,void* body0, void* body1);
+
+//bool bullet_contact_destroyed_callback(void* userPersistentData);
+
+/* ---- Bullet physics engine and algorithms ----------------------- */
+
 btDefaultCollisionConfiguration *Physics::physics_configuration = 0;
 btCollisionDispatcher *Physics::physics_dispatcher = 0;
 btSequentialImpulseConstraintSolver *Physics::physics_solver = 0;
@@ -26,6 +63,9 @@ void Physics::init()
 	physics_dispatcher = new btCollisionDispatcher(physics_configuration);
 	btGImpactCollisionAlgorithm::registerAlgorithm(physics_dispatcher);
 	physics_solver = new btSequentialImpulseConstraintSolver;
+	
+	// set custom bullet callbacks
+	gContactAddedCallback = bullet_contact_added_callback;
 }
 
 void Physics::done()