diff --git a/src/AIModel/AIMultiplayer.cxx b/src/AIModel/AIMultiplayer.cxx index 41d10d6c9..f46cbfb00 100644 --- a/src/AIModel/AIMultiplayer.cxx +++ b/src/AIModel/AIMultiplayer.cxx @@ -319,35 +319,53 @@ void FGAIMultiplayer::update(double dt) int ival; float val; - switch ((*prevPropIt)->type) { - case props::INT: - case props::BOOL: - case props::LONG: - ival = (int) (0.5+(1-tau)*((double) (*prevPropIt)->int_value) + - tau*((double) (*nextPropIt)->int_value)); - pIt->second->setIntValue(ival); - //cout << "Int: " << ival << "\n"; - break; - case props::FLOAT: - case props::DOUBLE: - val = (1-tau)*(*prevPropIt)->float_value + - tau*(*nextPropIt)->float_value; - //cout << "Flo: " << val << "\n"; - pIt->second->setFloatValue(val); - break; - case props::STRING: - case props::UNSPECIFIED: - //cout << "Str: " << (*nextPropIt)->string_value << "\n"; - pIt->second->setStringValue((*nextPropIt)->string_value); - break; - default: - // FIXME - currently defaults to float values - val = (1-tau)*(*prevPropIt)->float_value + - tau*(*nextPropIt)->float_value; - //cout << "Unk: " << val << "\n"; - pIt->second->setFloatValue(val); - break; - } + /* + * RJH - 2017-01-25 + * During multiplayer operations a series of crashes were encountered that affected all players + * within range of each other and resulting in an exception being thrown at exactly the same moment in time + * (within case props::STRING: ref http://i.imgur.com/y6MBoXq.png) + * Investigation showed that the nextPropIt and prevPropIt were pointing to different properties + * which may be caused due to certain models that have overloaded mp property transmission and + * these craft have their properties truncated due to packet size. However the result of this + * will be different contents in the previous and current packets, so here we protect against + * this by only considering properties where the previous and next id are the same. + * It might be a better solution to search the previous and next lists to locate the matching id's + */ + if (*nextPropIt && (*nextPropIt)->id == (*prevPropIt)->id ) { + switch ((*prevPropIt)->type) { + case props::INT: + case props::BOOL: + case props::LONG: + ival = (int)(0.5 + (1 - tau)*((double)(*prevPropIt)->int_value) + + tau*((double)(*nextPropIt)->int_value)); + pIt->second->setIntValue(ival); + //cout << "Int: " << ival << "\n"; + break; + case props::FLOAT: + case props::DOUBLE: + val = (1 - tau)*(*prevPropIt)->float_value + + tau*(*nextPropIt)->float_value; + //cout << "Flo: " << val << "\n"; + pIt->second->setFloatValue(val); + break; + case props::STRING: + case props::UNSPECIFIED: + //cout << "Str: " << (*nextPropIt)->string_value << "\n"; + pIt->second->setStringValue((*nextPropIt)->string_value); + break; + default: + // FIXME - currently defaults to float values + val = (1 - tau)*(*prevPropIt)->float_value + + tau*(*nextPropIt)->float_value; + //cout << "Unk: " << val << "\n"; + pIt->second->setFloatValue(val); + break; + } + } + else + { + SG_LOG(SG_AI, SG_WARN, "MP packet mismatch during lag interpolation: " << (*prevPropIt)->id << " != " << (*nextPropIt)->id << "\n"); + } } else {