Thanks for the save. I was partially right, my explaination was correct. However, unfortunately it's not the only condition for successful OMF change. Only some missions can be exploited by it, because most of them change OMF twice: on mission activation (entering the marker) and on mission start (after fade). Unfortunately both Home Invasion and House Party are not usable for the glitch.

Although my assumption was correct and I will try to modify some save before Grove 4 Life to make duping possible.

On last cars in memory: game generally keeps two latest entered cars unless they are mission tied. In your case, truck from trucking is mission tied and isn't used in player vehicles array, and there was only one vehicle you entered after Maverick/NRG.

You have to start the mission before the call happens. Only then the mission flag will be set to 0. But I am not sure if this can be done in all circumstances. The phonecall should be active, but delayed for some reason, like previous mission just finished or something like that.

Also maybe the method I described won't work at all, then it is about timing. It has to work if you start the mission within 150 ms after the phonecall call thread is started. In this case OMF has to be set to 0.

Btw, I would really appreciate a save with scheduled phonecall to run some tests myself OpieOP

Update.

I analysed the conditions for the glitched call. I may be wrong, but it seems to be working this way. There are two types of glitched calls. If a player has a progress with a girlfriend of -15 or lower (but not -100 and -999, probably constants for killing girlfriends), then the call will be generated as only player gets within a rectangle of 65 meters with her house in the center.

The second type is a usual call, when progress is higher than -15. If a player is within the same rectangle, then game chooses random hour and random minute for next call. This call would happen only if player is within that rectangle again at generated time.

It is possible that while waiting for chosen time no "consistent" calls can happen, and maybe it can be reset by dating another girl.

This is just an analysis of scripts, I didn't test it ingame, but maybe it will shed some light onto this call.

I have found what leads to OMF == 0 with girlfriend. It's an error in phonecall thread after all.

thread 'MOB_GF' .. :MOB_GF_38 wait 150 gosub @SUB_GET_TIME_FROM_LAST_CALL

This subroutine gets time from last call and uses $TIME_FROM_LAST_CALL_GOT_FLAG as a flag that the time was calculated. This flag equals to 0 in some cases like being in interior, being in a car and so on. But most notably it is set to 0 if player is on a mission.

Every phonecall thread checks this flag and if it's 0 it just goes back the start again. In case of a girlfriend call it's not the case: if $TIME_FROM_LAST_CALL_GOT_FLAG == 1 else_jump @MOB_GF_1050 :MOB_GF_1050 08C0: clear $391 bit 11 gosub @SUB_END_CALL end_thread In girlfriend's case it prevents from further calling, and behaves like player missed this call (hence the progress decrease). This includes setting OMF to 0: :SUB_END_CALL .. $ONMISSION = 0

So the thing is, player is scheduled to get a girlfriend phonecall, but suddenly starts a mission. This leads to abandoning a phonecall and setting OMF to 0, even though OMF was set to 1 by a mission, not a phonecall.

The only question is when a call is scheduled for.

I tried to see how onmission flag can be related to gf progress and unfortunately haven't seen any connections. Phonecall on the other hand can affect it. I tried to track down what creates a phonecall thread and found two such instructions, one of which was definitely a planned phonecall with random time of call, the other seems to create a call thread right after some event. Unfortunately, girlfriend agent script is complicated and I didn't find any obvious relation.

The best thing of course is to turn scm-code into something more readable, understanding meanings of all variables, but that's not too easy.

Of course, I may be wrong with the real cause of onmission flag change, but I just couldn't find anything like that around girl progress change instructions.

BubbleBobbler is right, sorry for inaccurate description. Every time state is changed, new random number between 30000 and 50000 is generated.

This is not even a glitch, but rather an explaination of a game mechanics, that may be useful in runs.

Unlike previous versions of GTAs, San Andreas has both police bikes and police cars. However, game doesn't choose random vehicle among these two. At each moment of time, game is guaranteed to have only one model loaded in memory, and even if it has both, it it still determined which one will be used as police vehicle.

There is a special flag, that defines which vehicle will be loaded (no matter, random police vehicle in traffic, ot pursuit vehicle from wanted level, however, of no more than 2 stars). At the beginning of the game, right after player appears outside of interior, it sets default vehicle to copbike and chooses a random number between 30000 and 50000, the time in ms when value of this flag will be changed. This change, however, happens only if all of the following conditions are true:

1. player is outside of interior
2. player has less than 3 wanted stars
3. player is either in LS, SF or LV (not badlands, desert, etc)
4. mission script hasn't explicitly forbidden to spawn police bikes If any of these conditions is not satisfied, game will use cop car as a default vehicle and the state change time will not be updated (until all the conditions are true again).

How does it work: at the beginning of the game, for a period of 30 to 50 seconds, game's default cop vehicle is cop bike. Any time game decides to spawn a police vehicle it will be a bike. After it the state changes, default cop vehilcle is LS cop car, and this lasts for a period of 30 to 50 seconds and so on.

About condition 4: there are two missions that forbid cop bikes to spawn, which are Drive By and Cop Wheels. This explains why a cop bike spawning trick works at the end of Drive By: right after mission ends, game state is released, and since time condition has been satisfied a long time ago, it immediately changes to cop bike.

Now a little bit about thing I am not sure. The fact is that it's not only a vehicle that is loaded, the driver model is loaded as well. And the possible thing that I didn't test is that with loading a new vehicle and a driver game may add the old ones to possibly unnecessary models. As far as I know, cop car driver is the same model as a usual cop. So if the default vehicle is cop bike it may be possible that there will not be on-foot cop spawns at this time. This may explain why sometimes during Big Smoke there are no cops on the street.

I found out how exactly parachute is given when player leaves the plane or heli (which is used in NOE). Here is is short video (sorry for horrible quality): Parachute is given after player leaves the plane or heli only if the timer shown on video is not equal to 0. The timer is set to 5000 when player is in plane/heli and the camera position (not the vehicle itself!) is at least 50 meters above ground level and it is currently at 0. Otherwise during each frame its value is decreased by a length of a frame.

This (if I understand correctly) means that getting parachute on the hill in NOE is inconsistent because it depends on value of timer when camera starts being lower than 50 meters above ground. On the other hand, using rock (as in video) can be a guaranteed way to get a parachute. Pay attention to the fact that it is possible to put a camera in such a position that it is acutally not above rock, but above ground, that sets the timer to 5000 if it reaches 0.

Patriot is for some reason unreferenced by game script after player damaging one of Waltons. Most likely this is just an overlook of developers. So to avoid despawning, you can't be too far from Patriot or always keep it on the screen after damaging first of Waltons. If you enter it after it, it can't despawn.

I've tried to track down what exactly causes heli to despawn during Lance pickup cutscene and now I can share my findings.

In fact, the heli despawns even before player reaches Lance as game thinks that it is not needed just like some faraway random traffic. Usually it doesn't happen, because (unless vehicle is tied to a mission) last 2 player's cars are specifically prevented from despawning. However, the thing is that heli can be removed from player's vehicles list and it leads to a despawn.

What leads to this removal? It's an strange behavior of ped's AI process. Vehicle is removed from this list if there is a ped that has the vehicle as a target and (this is just a hypothesis, but it seems realistic) game can't find coordinates that can be used for jacking it. In fact, it is guaranteed to be removed from list if a left door is blocked. So if you exit the heli through the right door, it is guaranteed to despawn. However, exiting through left door doesn't guarantee anything. At first, if a door was blocked at any moment after entering junkyard (when guys become hostile), it is removed already and further maneuvers don't matter. Secondly, there are cases when door was never fully blocked, but the vehicle is still removed. I am not sure what exactly causes it in this case, but I have two ideas: first, the safe area used for this calculation is slightly bigger than used for actual entering, second, the path can't be created to those coordinates (the way to a door is blocked). I don't know exact answer, though.

So, if you feel that at some point left door was blocked or was in awkward position, you can quickly relocate it to a safe position, exit it, immediately enter it again and exit it again. If the position was safe, this should prevent it from despawing.

Duping taxi before is not necessary. It is enough to start and cancel it, then do vigilante taxi start.

In fact it's the same technique that is used in instapasses. Taxi mission is just skipped to the point when a destination is generated and it happens to be an offset corresponding to Washington Beach. The only thing that can fail is the fact that due to a skip game originally doesn't know which car Tommy uses. This value is initialized by regular starting taxi driver and cancelling it. The only condition is that the car that was used for original taxi start is still alive, at least for a few frames before the other copy of taxi driver finds player's vehicle.

Also it counts as one fare since the other copy of taxi driver works as intended and waits for chosen ped to enter cab.

There is totally useless coding error in High Stakes, Low Rider, so weird that one may say it was made deliberately. If you fail High Stakes, Low Rider mission (not the race itself) in any way except destroying your own car, the screen will turn black. It's usual fade (just like when starting missions) but without set ending value. If you fail the mission by getting wasted or busted, the fade will be reset, but if you manage to destroy Cesar's car, the fade will stay. Also all sounds will be removed, but they work fine after pause. Fade is removed if you manage to get to mission marker, for example, or if you die or get busted.

To destroy Cesar's car, get a parachute and hit the car while having parachute equipped. Maybe his car can be pushed to the water, that would "destroy" it too.

The glitch does not work during the race itself (it's technically different mission) and with other cars (destroying them doesn't fail the mission).

Yes, it would

Crash depends on which camera was chosen at the start of Chaperone. If you see this camera, then game will crash on Blowfish instapass: ($2033 = 3) These cameras are fine: ($2033 = 2) ($2033 = 1) ($2033 = 0)

Unfortunately this instapass will crash the game with 25% chance and nothing can be done about it. Edit: nvm, you actually can by restarting Chaperone

During missions with people following you, it is possible to shoot at yourself.

One of the best glitch I've ever heard of is so called hobos tunnel glitch. It is well known that there is a fixed spawn of 4 hobos in Portland tunnel near 8-ball's. Take a high enough vehicle (Rumpo is fine) to this tunnel and stop not far from them. Jump on top of the car. You'll notice that hobos start moving. Wait a little bit and drop to ground. New 4 hobos will spawn. Keep doing it until a fairly noticable graphical change will happen (it happened to me after 30 respawns). After it you may leave the tunnel and watch how the city looks like. Spending time in this "mode" leads to further graphical changes.

Spawning even more hobos eventually leads to game crashing because, as far as I know, ped pool can't contain more than 140 peds.

This is a risky trick but luckily with more or less a fail-safe method. The start is usual: start Evidence Dash and reach on_mission == 0. After it the most risky trick has to be executed. The thing is that if you just enter the marker, one copy of Gangcar Round-Up will instapass (the one that was originally Evidence Dash), the other will still be running and since instapassing will set on_mission to 0 again, Kingdom Come will start (the player stays in the marker). And this would crash the game.

So how to avoid this? You have to activate mission while still moving and exit the marker by the end of the movement. However since the game activates this particular mission only when player is not moving (not using keyboard as far as I understand), there is only one way to execute this trick: by jumping off the phone. The most consistent way in terms of fail-safety in shown on video. Mission will start, one copy will instapass and the other will still be running. If may require a few tries but it shouldn't crash the game.

To cancel the other copy of mission you need to start vigilante. The next problem that now both Kingdom Come and Gangcar Round-Up are available. If you immediately enter the marker, first mission to start would be Kingdom Come with Gangcar Round-Up being second. As we know, this leads to the second of the missions to be active. However after reloading the game the order of mission-starting scripts will reverse. So Kingdom Come will be activated. It can be passed normally, however you have to start vigilante after its completion once again because one more copy of Kingdom Come will still be running.

This instapass works for 100% only since it doesn't affect mission counter. However the percentage is increased.

Also thanks to Powdinet for original discovery of instapass and video.

As it was suggested, weather is fixed in GTA III. There are 4 types of weather: sunny (0), cloudy (1), rainy (2), foggy (3). Here is the array of weather loop: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 01 02 02 01 00 00 00 01 03 03 01 00 00 01 01 00 00 00 00 00 00 00 00 01 01 02 02 01 02 01 00 00 00 00 00 00 00 00 00 00 03 03 00 00 00 02 01

Weather changes only when another hour advances. Sometimes (like sunny->fog) change doesn't happen immediately. The first weather is fixed, it is 1 (cloudy) up until 8-ball is spawned after safehouse cutscene. After it next hour advance will mean that the current weather will be set to 0, element #2 of the array (first 0 it skipped). At next hour advance the weather will be set to 0, and previous weather will be set to 0 as well and so on. There are 3 missions that lock weather the same way: Blow Fish after Trashmaster is in fish factory until the end of the mission, Last Requests from getting to boat until the end of the mission, and Gone Fishing from the start to finish. During these missions running under these circumstances the weather loop will not advance (so weather changes will be postponed). Similarly, arriving too late at safehouse (approximately 4:46 and later) will pospone it as well. The Exchange locks weather as well during ending cutscene until mission end.

Cartel can also be spawned by entering any car.