High Kerbs, Low Kerbs, No Kerbs?
The most basic way of manipulating kerbs is done in the TRACK CHANGE DIALOG box. From here you can choose to place a kerb on the left or the right or both sides of the track, or to have no kerbs at all, which is done in the KERB section of the TCD box. The other option available to you here is to set a HIGH or LOW kerb. This is done in the ROAD SIGNS area of the TCD box. For a HIGH kerb, don't worry about this at all. To set a LOW kerb, check the box marked '0x4 Kerb Selector'. N.B. Sometimes when a low kerb is set in a track section where there was previously no kerb or a high kerb, no kerb will appear at all, or it will not fill the entire length of the track section. This can be fixed, so read on. N.B. When there are kerbs on either side of the track, they BOTH will be either high or low, depending on what you set them too. I don't believe that you can have one high and one low. In the Editor, high kerbs are a blue dotted line, low kerbs red.
Kerb Characteristics. (Commands 0xca, 0xcb)
You may have noticed that kerbs vary from track to track, from the wide, flat kerbs of Jerez, to the evil things you'll find in the Hockenheim chicanes. All of this is defined in the above mentioned commands. I'm fairly certain now that 0xca defines the characteristics of HIGH kerbs, and 0xcb LOW kerbs. Each command occurs only once in each track, and are found in the zero track section (the exception is Adelaide, where it is found in the number six track section. And no, I can't explain why Adelaide is as such). Each command has five variables which are as follows: Variable 1 - Unknown? (Possibly unused) Variable 2 - Kerb Profile Variable 3 - Kerb Width Variable 4 - Kerb Height (at track edge) Variable 5 - Kerb Height (at far edge of kerb)
I'll leave Var2 till last as it is dependent on the values of Var3, 4, and 5.
Variable 3 - Kerb Width Pretty self explanatory. Low value gives a narrow kerb, high value gives a wide kerb. Can be as low as zero, which means no kerb (perhaps you should have just set no kerbs instead?), and a realistic highest value is 350. Those who need it any higher should perhaps consider a change in setup, or longer applications of the brake pedal! N.B. Don't take this as read, but I think that when the distance between the track edge and the wall is less than that of the kerb (This is trial and error, as wall distance is in different units to kerb width), the kerb will not appear. I think that this is what happened to me at the bus stop chichane exit at Spa, but I'm not absolutely certain. As always, experiment.
highprof.gif: W=300 H(T)=1 H(B)=25 P=0. High profile
(low value)
medprof.gif: W=300 H(T)=1 H(B)=25 P=150. Medium profile
lowprof1.gif: W=300 H(T)=1 H(B)=25 P=300. Low profile
(high value)
lowprof2.gif: W=300 H(T)=1 H(B)=25 P=300+. (350 here)
The profile value actually determines how far along the width of a kerb it will be flat, and will rise to the kerb edge (bank) height from this point. This kinds of discredits the convex/concave theory, but that idea is close and easy to understand. N.B. The closer the value of the profile is to the kerb width, the more stupid a kerb becomes (look at the pics) Use about 0-3/4 Width as a realistic range of profiles.
As a final note on the 0xca and 0xcb commands, GP2 will only read one of each command for every track. So placing one of these further into the track in hope of changing a particular kerb or all the kerbs of that type following will not work. GP2 will read this command, but it will override the same command in the zero (Adelaide- 6) track section, and use it for the entire track, more's the pity. N.B. I have defined the high and low kerbs from how the kerbs are made in the original Microprose tracks. If you so desire you can make a 0xca HIGH kerb a low kerb by changing values around, and a 0xcb (0x4) LOW kerb high. Whatever gets you excited, I guess!
Kerb Placement (Commands 0x8e, 0x8f)
These two commands determine where along a track section or sections a kerb will be placed. These commands are to be found (rare), or can be placed, in any track section that will accept a kerb. 0x8e appears to apply to kerbs on the left hand side of the track, and 0x8f the right. Each command has three variables, which are as follows: Variable 1 - Unused Variable 2 - Start position in track section Variable 3 - Length of kerb.
As far as I know, a high kerb (non 0x4) can be placed anywhere and will always fill the entire length of the track section so you will use these commands more frenquently on low kerbs (0x4).
Variable 2 - Start position in track section This defines how many length units into a track section a kerb will begin. This value is in the same units as the track lengths. N.B. Depending on the values you use, kerb adjust commands can be used to affect kerbs in following sections as well, as long as there are kerbs set within the following sections. This is true for the length value, and it is also possible to set the start position to greater than that of the track section length the command is set in, so that the kerb will begin in the following section/s. You may wonder why you'd do this but it could be quite useful to you, as I'll explain later.
Variable 3 - Length of Kerb This variable sets how long a kerb will extend from its start position. As mentioned above, as long as a kerb has been set in the following track section/s, the added value of the start and the length can be greater than that of the track section the command is in, and so you can determine how far the kerb will extend into these sections. The alternative to this is to set commands in these sections as well, but that is slower. Where the kerb adjust commands are really useful is on low (0x4) kerbs. Occasionally when you set a low kerb on a track section, it won't run the entire length of the section or will not appear at all. I've shown you how to fix the first problem, but now I'll tell you how to 'force' a low kerb. There are some cases in GP2 where you want to replace a high kerb with a low kerb in a chicane, but when you do, no kerb will appear. The Casio Chicane at Suzuka and the fist chicane at Monza have this problem.
What you need to do is to find the last track section before the one where you want the kerb that WILL ACCEPT a low kerb on the SAME SIDE of the track. Set a low kerb for this section, and place a 0x8e or 0x8f command in it depending whether it is on the left or right hand side of the track. We'll assume that you don't want this kerb to appear on the track. Now you'll need to add up the lengths of this track section, the track section where you want the kerb, and any in between if that is the case. Let's say we have our kerb command on a track section of length 10, and we want the low kerb on the next section, which is of length 5. With low kerbs set on both track sections, remember, set the start to 10 and the kerb length to 5, and you've got a low kerb where you want it, and no kerb in the preceding section where you don't. If you don't want the kerb exactly as I explained, fiddle around 'til it's how you want it. N.B. It appears that when there is a pit entrance/exit in the middle of a kerb placement command region, the above example won't work. Sorry, but I can't do anything about that.
Individual Kerb Height Adjustment? (Command 0xe0) I suspect that this may have nothing to do with kerbs at all. If anybody can clear this up, email me at the address at the bottom of the page.
Just a little bit of extra trivia here. Each circuit has a JAM file called pavXXXXX.jam (xxxxx being the abreviated name of the circuit), in it's own directory. There are two kerb textures printed here, one near the top, running across the full width of the page, and one near the bottom, likewise. The top texture will be displayed on 0xca kerbs, and the bottom texture is displayed on 0xcb (0x4) kerbs.
Questions, corrections, hate mail, love letters, or bomb threats to Nic Prins n2176572@sparrow.qut.edu.au