fix collision events for sleeping pairs, closes #1077

src/collision/Pairs.js

@@ -64,9 +64,6 @@ var Common = require('../core/Common');
  if (pair.isActive) {
  // pair exists and is active
  collisionActive[collisionActiveIndex++] = pair;
- } else {
- // pair exists but was inactive, so a collision has just started again
- collisionStart[collisionStartIndex++] = pair;
  }
 
  // update the pair
@@ -89,16 +86,21 @@ var Common = require('../core/Common');
  for (i = 0; i < pairsListLength; i++) {
  pair = pairsList[i];
 
- if (pair.timeUpdated < timestamp) {
+ // pair is active if updated this timestep
+ if (pair.timeUpdated >= timestamp) {
+ // keep active pairs
+ pairsList[pairsListIndex++] = pair;
+ } else {
  pairSetActive(pair, false, timestamp);
- collisionEnd[collisionEndIndex++] = pair;
 
- // remove inactive pairs
- if (!pair.collision.bodyA.isSleeping && !pair.collision.bodyB.isSleeping) {
+ // keep inactive pairs if both bodies may be sleeping
+ if (pair.collision.bodyA.sleepCounter > 0 && pair.collision.bodyB.sleepCounter > 0) {
+ pairsList[pairsListIndex++] = pair;
+ } else {
+ // remove inactive pairs if either body awake
+ collisionEnd[collisionEndIndex++] = pair;
  delete pairsTable[pair.id];
  }
- } else {
- pairsList[pairsListIndex++] = pair;
  }
  }