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"Pure" racing tracks are back in fashion it seems  

Track spoilers : You will find a few unusual track sections when racing Presto. If they feel too bewildering after your first try, read on...

• The bridge chicane. Don't be confused by the optical illusions and just drive it as a walled right-left chicane. By finding the right breaking point and trajectory you should be able to drive it at least as fast as a conventional small corner.
• The fast chicane with barriers. The solid bridge pieces being used as barriers are there to prevent fast grass shortcuts. So what you need to do is to keep the car on the asphalt, especially through the middle part of the chicane, and you should be fine.
• The final section. Again, don't be scared by the special effects and just drive straight through the jump and to the finish as fast as possible.

As for the rest of the track the key point is finding an effective trajectory, potentially using grass cuts, speed adjustments and maybe controlled slides. That is especially true for the tricky sections after the loop and the banked road stretch, where there are multiple reasonable racing lines to choose. In general, however, there is one easier way to do a section if you'd prefer to think about it later. Having a good look at the track map helps too...

The key message is : don't get scared!

A while ago I asked dstien and clvn for the toolkit they are using for the reverse engineering stuff so that I could fool around a bit with the disassembled code. Goals of doing so include understanding the basics of assembly, performing some analysis which might some day be relevant to their porting efforts and, if possible, finding possible immediate targets for modding in the .EXE itself. As for the latter of these goals, there some interesting and maybe even useful modifications which are possible already, but I won't give details until they actually come into fruition in order to avoid creating vaporware. Thing is, inserting any piece of code into an existing executable may require fixing thousands of memory addresses, and even trivial modifications can become complicated due to issues such as the way the code is optimized, which reduce a lot the flexibility of the "dirty" approach to hacking I am forced to take (as I can't code neither C nor assembly properly).

There is, however, one very amusing discovery which was made possible by understanding how track elements are built. To make a long story very short, after the game reads a tile value from the .TRK it uses it to load a chunk of data which contains all relevant information about the track element. Within this piece of data, there is a number which tells the game what the physical model of the element should be. The number points to one of many branches of code in one particular place of the .EXE. When you drive through a track element, the game (among many many other things) runs through the branch assigned to the element, where it uses the car coordinates to decide what the car will have to face (whether there will be a sloped surface at that particular position, or ice, or a wall...).

These branches of code (there are around 50 of them IIRC) are a royal mess to understand for even slightly complex track elements. But for flat roads and corners they are not complicated at all. For a straight road all it does is check whether the x coordinate of the car is between +120 and -120 (the limits of the paved part of the track). If so, it sets a flag which assigns the correct paving (asphalt, dirt or ice). If not, it will just default to grass. Corners (both small and large) are pretty much the same thing, except that before checking the boundaries the game calls a helper routine to trace a circumference to be used as centerline instead of a straight line, and then checks the +-120 limits around the relevant part of the circumference.

Now, something funny happens when you read the code for chicanes. Initially I expected to find either some glaring obvious bug to account for fast grass or nothing at all. Instead, there is a neat little bit of code which makes use of the large corner routine. It looks somewhat like this:



"Very clever!", one might think. By mirroring the tile along x and z axes whenever you cross to the right half of the element you should get two symmetrical half-corners which, when connected, make a chicane. A nice solution in theory. But there is a slight problem, which can be better explained with this pic...



This is the result of a quick n' dirty Stressed experiment in which I mirrored the four tarmac segments at the end of a corner along x and z and strapped them at the other end, which is roughly what the code I described is supposed to do. As you can see, it doesn't quite match...

But, if the code is broken, whatever happened to our chicanes? The answer is discreetly nested in the "few extra lines" I mentioned in the diagram. In fact, I can even picture how the developing team came to the actual solution. They probably were in the final stages of design and decided to code the chicane as an afterthought, after someone came up with the idea of mirroring a half-corner. Soon enough, however, they noticed it wasn't working as expected. By that point they must have been in a rush to finish the game already, and so instead of trying to figure out how to fix it they chose the "screw it" route and added this little coding gem, which looks like this in assembly:

mov     al, [bp+var_12]
mov     byte_44D47, al

What does it do? Simple answer. [bp+var_12] is the flag which indicates the track surface associated with the OWOOT part of the chicane (asphalt in this case), and byte_44D47 is the flag which tells the game on which kind of surface the car is currently on. By copying one to the other this early in the code they assured the whole four-tile area of a chicane would behave as asphalt, regardless of whatever broken code they left behind.   And thus fast grass was born - not as a true bug, but rather as a, hmm... "crude"   improvised solution to avoid having an obviously broken track element.

(In case you are wondering, I am trying to work out a way to disable the fast grass "feature". But more on that later on... )

The classic PHP track viewer by Jonas Baehr is now out of order, so I wrote a new one.

http://scr.stunts.hu/trkview.php

It is fully functional already, but I will likely make some small improvements. It was designed to be lightweight and modular, so that the code can be reused in other contexts (say, in an online track database browser). I will gladly share the sources and comments if Zak or other site owners are interested. Feedback is appreciated as well, of course. Have fun!

An "Awards" section was just inaugurated with the awarding of the first Alpha Crux Medal to Mark L. Rivers for his title on the 2009 season. Visit it here. Southern Cross is still a operational organization, so more events are expected to be held eventually - and you will be able to challenge for a Medal too 

How come we didn't have this thread yet? Big rule changes, major driver line-up reshuffling, several new teams, last-minute financial dramas... and some of the best-looking cars in a long while - please vote on the poll! (you can change your vote later to account for still unreleased cars)

I propose ZCT105 to be somehow a hacking-themed track in order to celebrate the 2 year anniversary of Dstien's revolution and next-gen Stunts modding.

First, a rule interpretation question. Does the sanity-check "you must cross the finish line rule" mean you need to cross the line on the road (that is, passing under the banner), or are other ways of crossing the line (through the grass, from the "wrong" direction with penalty time, etc.) valid as long as you do cross the start/finish tile?

Also: come on and race, folks! The track is short enough for everyone to be able to drive at least one lap... 

Here is a quick test on the evenness of car choices along the races with the bonus system. I only included races from Z91 onwards to avoid flawed conclusions - it is known that 2008 rules resulted in bonuses which tended to favour PG cars. The method consisted in adding points for cars in each race as if in a normal scoreboard. In order to give extra weight to podium results, I chose to deploy the 2009 F1 scoring system (1st to 8th receive points; 10-8-6-5-4-3-2-1). Here is the overall rank:

Countach: 67
Skyline: 56
Ranger: 47
Ferrari: 46
Lancia: 41
Audi: 40
Corvette: 39
Carrera: 35
LM002: 33
Speedgate: 32
Acura: 22
P962: 18
Indy: 18
Jaguar: 13

Comments:

• Most cars are in the 30-40 range. Considering the maximum score for a single race is 39 and that there are more cars than tracks in a season, that fact speaks well of the current bonus system.
• The cars topping the rank either were used by most pipsqueaks on a track but failed to win it (Countach @Z93, Skyline @Z94, Ranger @Z95) or were used exclusively by the winner on a race (Ferrari @Z91) and ended up resurfacing late in the season. Nothing wrong with that.
• Cars lying low on the rank are now, after the averaging of bonuses for the new season, in a good position to be deployed in 2010. Audi, which was largely ignored through 2009, already dominated Z103; the IMSA cars will likely play a major role on the next few races and Indy and NSX (which were arguably over-used during 2008) will surely appear again by mid-season when their bonuses accumulate a bit more.

Thumbs up for the bonus system, I guess  In case anybody is curious, here is the full "season scoreboard" copy-pasted from OpenOffice Calc:

Code Select Expand


Z91 Z92 Z93 Z94 Z95 Z96 Z97 Z98 Z99 Z100 Z101 Z102 Z103
ANSX 22
AUDI 8 32
VETT 39
FGTO 10 31 5
RANG 17 30
JAGU 1 10 2
COUN 28 39
LANC 2 39
LM02 4 29
NSKY 17 39
P962 18
PC04 35
PMIN 18
GATE 4 9 10 9


...for a week. Since the Holidays season left me in a super-lazy mood, I will only get down to racing on all those wonderful tracks when I return. But I promise to come back with a vengeance, or something like that   

Feel free to let me know how did you feel about the tracks, the management and everything else - it surely can will be useful for a novice like myself!

Initial draft just finished, right now I am in the process of sorting the good ideas from the stupid ones (current ratio is about 50:50). As for the car, please refer to this post by Bonzai Joe  

Track building started today. So far I can tell you two things about the next round. First of all, expect a long track, as I do not think I'll be able to pull off the desired effect with a standard-length circuit (those of you who raced or followed JACStunts will have a rough idea on what to expect). Second: a key design goal this time is making the track as beautiful as possible  

This competition needs more of you. Who else would better show us the way around the roads?

[epic]

The sense of anticipation and excitement Mark mentioned on the news page is very real - Z100 is shaping up to be The Race, indeed. I mean, it's not everyday we have the chance of reuniting so many stars from different eras in one single race. In fact, with the recent comebacks it seems we're very close to getting all of the champions in it! Roy and Renato are already on Z99. Soon enough, BJ will have his DOSBox setup up and running, and CTG will find a bit of time to rejoin the fight. Ayrton and Gutix were racing earlier this year, and it probably won't be so hard to bring them back (c'mon Rotoi, time for the MeganiuM Red Alert!  ). Only Alain remains missing - but at the very least his (digital) whereabouts are known, thus a convocation can be issued. That would be simply epic, and not to mention all the other pipsqueaks which are to take part...

Since people do not seem to be very keen on racing Battery  )-: , I'll leak some info on the forthcoming track. I already have a design concept set, and a track draft that portrays very well what I want the circuit to be like. Problem is, the draft is (as they always are) slightly too long (~1:50) and, more importantly, it has a jump over the start/finish line, which would mean mandatory penalty time or worse.

Anyway, expect something completely different from the current track.

I have been wondering a bit about some historical records that might change hands in the near-future. For instance...

• Most podiums in a row: obviously Ayrton has 12 consecutive podiums (all these victories in 07/08). I wonder if anyone had topped that before. Maybe Roy or some other early champion?
• Longest gap between victories: BJ took this at the start of the year (Z62...Z91). But now we have three strong potential claimants on the scoreboards...

(Original title: Track 2...)
...is being designed right now. First draft was almost two minutes long so I'm shortening it a bit. I still haven't decided which car will be used...   although my shortlist has only two viable options at the moment.  

[The Southern Cross Stunts Trophy]

It's with the utmost satisfaction I announce the launch of a new competition:

The Southern Cross Stunts Trophy

Some of the main facts about the tournament were already leaked in the discussion threads we had here; now it's time to confirm them:

• IRC rules;
• Five rounds with three weeks each;
• First race will start at August 3rd (a Monday - deadlines will be on Sundays)

Other details (such as the preliminary rule code and a tentative schedule) are already available at the competition site: http://scr.stunts.hu , so I kindly invite you all to check it. And please report any bugs, broken links, Internet Explorer issues, layout suggestions, etc., as small as they may be - I have no web access at home right now, so I will have trouble to test things properly in the following few days.

See you on the scoreboard... in August  

1. Duplode (*)
2. Alan
3. Friker
4. BJ
5. CTG
6. Zak
7. para-Mingva
8. SuperBrian
9. Chulk
10. dstien

(*) This is just for, after I lose this race, illustrating to Alan why I do not bet on my own victories