BGE physics: When colliding, report first contact point to Python

This patch adds two parameters to the functions in the
collisionCallbacks list. The callback function should thus be like
this:

```
def on_colliding(other, point, normal):
    print("Colliding with %s at %s with normal %s" % (other, point, normal))

game_ob.collisionCallbacks.append(on_colliding)
```

The `point` parameter will contain the collision point in world
coordinates on the current object, and the `normal` contains the
surface normal at the collision point.

The callback functions are checked for the number of arguments
`co_argcount`. The new `point` and `normal` arguments are only passed
when `co_argcount > 1` or when `co_argcount` cannot be determined.

Reviewers: brita_, campbellbarton

Subscribers: sergey, sybren, agoose77

Projects: #game_physics

Differential Revision: https://developer.blender.org/D926

1 files changed, 21 insertions, 3 deletions

diff --git a/source/gameengine/Ketsji/KX_TouchEventManager.cpp b/source/gameengine/Ketsji/KX_TouchEventManager.cpp
index 7ec379eec26..eb774960d41 100644
--- a/source/gameengine/Ketsji/KX_TouchEventManager.cpp
+++ b/source/gameengine/Ketsji/KX_TouchEventManager.cpp
@@ -60,7 +60,7 @@ bool	KX_TouchEventManager::NewHandleCollision(void* object1, void* object2, cons
 	PHY_IPhysicsController* obj1 = static_cast<PHY_IPhysicsController*>(object1);
 	PHY_IPhysicsController* obj2 = static_cast<PHY_IPhysicsController*>(object2);
 	
-	m_newCollisions.insert(std::pair<PHY_IPhysicsController*, PHY_IPhysicsController*>(obj1, obj2));
+	m_newCollisions.insert(NewCollision(obj1, obj2, coll_data));
 		
 	return false;
 }
@@ -209,9 +209,11 @@ void KX_TouchEventManager::NextFrame()
 				}
 			}
 			// Run python callbacks
-			kxObj1->RunCollisionCallbacks(kxObj2);
-			kxObj2->RunCollisionCallbacks(kxObj1);
+			PHY_CollData *colldata = cit->colldata;
+			kxObj1->RunCollisionCallbacks(kxObj2, colldata->m_point1, colldata->m_normal);
+			kxObj2->RunCollisionCallbacks(kxObj1, colldata->m_point2, -colldata->m_normal);
 
+			delete cit->colldata;
 		}
 			
 		m_newCollisions.clear();
@@ -219,3 +221,19 @@ void KX_TouchEventManager::NextFrame()
 		for (it.begin();!it.end();++it)
 			(*it)->Activate(m_logicmgr);
 	}
+
+
+KX_TouchEventManager::NewCollision::NewCollision(PHY_IPhysicsController *first,
+                                                 PHY_IPhysicsController *second,
+                                                 const PHY_CollData *colldata)
+    : first(first), second(second), colldata(new PHY_CollData(*colldata))
+{}
+
+KX_TouchEventManager::NewCollision::NewCollision(const NewCollision &to_copy)
+	: first(to_copy.first), second(to_copy.second), colldata(to_copy.colldata)
+{}
+
+bool KX_TouchEventManager::NewCollision::operator<(const NewCollision &other) const
+{
+	return first < other.first || second < other.second || colldata < other.colldata;
+}