The freeway is definitely an under utilised vehicle in SA. I have always been jealous of VC and the ability of the freeway to land big air stunts there. However, I don't believe the freeway has been used VC in such a technical way as it has been used in SA and especially in this video.

Of note are the curved front side grinds on the highway on/off ramps. Those looked damn good. The finisher is also a really good find.

lovely vid 
so there is a mod with sparks in replay?

We are in 2024 bro: https://www.gtastunting.net/index.php?topic=72220.0

Sparks Replay Fix

Introduction

After, getting the wheels and suspensions of bikes to work in replays I set out to get sparks in replays. One of the two reasons why grinds in SA are so much lamer is that there are no sparks to show the friction of the body of the vehicle with the rail or ledge. The other being of course that grinds lose speed very quickly when FL is turned off.

Getting the sparks to work has been a real challenge. Once I got something to work something else would pop-up and would require twice as much work as needed before. In short these are the following bugs features I needed to implement. First of all the camera matrix did not update properly when using the replay system. This caused the sparks to always be flying towards the camera that was still at the position of the player outside of the replay. In SA sparks are dependent on the position of the camera and this is why they move when you rotate the camera.

Secondly, collision had been turned off when replays are playing. Collision detection is used to determine whether two objects are touching. Sparks are created inside this collision procedure, but only when certain speed limits are passed and some flags are enabled. This was understandable as enabling it causes all types of problems. When enabling it collision forces will still be applied when a collision is detected and because the replay system will update the position of the player every frame, this would give all sorts of weird interactions. After a lot of trial and error I was able to get it into a reasonably stable state. I hope the player does not go flying off in random locations anymore.

The sparks are only enabled for the player vehicle, when the player is riding it. I had to do it this way because of the aforementioned reasons.

All in all, I think I got it in a pretty decent state. It has taken many days and long nights of frantic disassembly scrolling and dealing with ASM bugs, and frankly I don't wish to work on this anymore.

Results

Here you can see the results on some simple grinds I landed with the script.

https://www.youtube.com/watch?v=aFSE0QgbUmk

Compatibility and Bugs

The replays generated when using this fix are able to be played when the fix is not active. It would look exactly the same as before. It should work with replays not landed with this fix. No data is read from the replay in order to get the sparks and therefore any old replay will do.

With cars there can still be quite some bugs and it can appear unstable. In general it seems to work okay, but the collisions around cars and their wheels are more finicky.

For some down-hill rails no sparks are created and during RADs there aren't as many sparks as in game. I am not sure if I can fix this problem. It may happen that the game does not detect any collisions, there is not much I can do about this.

I have not tested if it is compatible with freeplay or other .asi scripts but I foresee no problems there.

Download

You can download it here

Instructions

Put the .asi script in the GAME_FOLDER/scripts folder and use your favourite .asi loader to load it. I recommend Silent's which you can find here.

Disclaimer

I am not responsible for any corrupt replays if you choose to use this fix.

Thanks

Thanks people on the GTAS discord for their support along the way. I hope you can appreciate this work.

That's awesome, dope job . I wish to learn programming every time I see cool things like this.

Just do it.

I have a question based on the replay system's source code, I tried to read it but I could only understand so much as someone with zero programming experience. I was once under the impression that SA captures replay data every 40ms (25fps), but later down the line, I compared live footage to replays, and noticed that playing replays at 30fps is often closer to the actual game speed, particularly with FL off replays. This lead me to believe that SA might actually capture replays at 33.3*ms (30fps), and they're simply being played back too slowly due to SA's frame limiter being 25fps. Now that I've attempted () to read the replay system's source code, I'm questioning my conclusions.

Quote from: Replay.cpp

static uint32& s_FrameRecordCounter = *reinterpret_cast<uint32*>(0x97FB40); // STATICREF
    if (Mode == MODE_PLAYBACK) {
        PlayBackThisFrame();
    } else if (CTimer::GetTimeInMS() - s_FrameRecordCounter > 26) {
        s_FrameRecordCounter = CTimer::GetTimeInMS();
        RecordThisFrame();
    }

I might be understanding this totally wrong, but I'm guessing it means that with FL on, the game captures 25 frames into the replay buffer per second, and with FL off (26fps or above), it switches from calculating time in frames (25fps) to calculating time in milliseconds (40ms), to get the same amount of frames without suffering VC's variable frame rate replay issues, but without programming knowledge I'm probably just making stupid guesses . The main reason I'm interested is to try and match SA's replay recordings in future videos to game speed as closely as possible, and it seems like you have insight .

Speaking of game and replay speed, I have a second question if I may. It's known that SA's FL off replays are usually slower than FL on replays, but I'm not 100% certain why. I'm guessing they're slower either due to interpolation issues when the frame rate rapidly changes, or when the frame rate isn't a multiple of 25fps or 30fps (depending on which most closely resembles the rate of capture), but is that misguided? Your knowledge would be very helpful .

It is actually a bit of mystery to myself as well. It seems indeed that the game tries to capture a frame for a replay every 26 milliseconds. Which would make it record at 38~fps, but I'm not sure if this is actually the case. I have experimented before with this changing the value of 26 to other values and I remember that by changing it to 3 ms it would save replays at about 60 fps. However, this does not make much sense. Actually I believe the main game runs at 30 fps, but there is another performance delay that locks the FPS at 25 in the main game idle function. You can manipulate this delay by altering a single byte located at 0x53E94C. You can change it to 1 to have replays to play at 30 fps. You can do this easily with CheatEngine. With some more hacking it should be possible to record and play replays at any framerate, but this would change the way physics is processed and thus counts as modding.

Quote from: Reynard The Fox on December 31, 2022, 04:47:46 AM

Conversely, older replays are able to be played, but the wheels of bikes will most likely bug out. There is no actual bike wheel data so it tries to read whatever gibberish is present in the replay.

That's very unfortunate to hear. Do you maybe happen to have a visual example of how faulty it can look?
Also, does this count for the spinning wheels only or also the suspensions? Having those work independently could still make a neat lil improvement for older replays.

It counts for both spinning wheels and suspensions. It looks terrible actually, the wheels will jump all over the place moving quite far away from the bike at one frame and then completely on the other side in the other frame. There is no actual bike wheel data in normal replays.

This video was absolutely crazy. Really shows what is possible to do in stunting if only you are lucky enough. I wish we could leave this virtual machine and saved state bullshit behind us, but I fear that in the future people are still going to abuse it.

I love the shiny ass gold bike and all the interlude work. My favourite stunt was the ledge grind around the corners switching from front to back. It is so pleasing to see. The combo in the LS was also insane. The little bump the bike does on the finisher is just too perfect, even for a TAS video!

Great work Dannye! This should not be very hard to port to SA as the replay system is nearly identical as most methods seem to be the same. One would just have to identify the mentions of the buffer in these methods. I'm not sure if this is needed in SA at all as replays can be quite long already.

Quote from: DeathCobra on August 01, 2022, 09:33:19 AM

Ah neat. I thought it was the old close packer on Infernus psm from bitd

I was actually first to do this multiple times in this video: https://youtu.be/q0-IeYLkiis
In those cases the packer is stuck by driving the packer ramp into the traffic light. But the same principle applies the ramp is lifted and that is bumped. I think a lot people assumed I did the third car stuck but this is not the case.