Converting Grand Prix Legends Tracks:
Thanks to the GPL2TRK tool created by T. Fastwalker we can convert GPL tracks to N3 and ICR2 relatively fast. This is not as straightforward as it may sound, because it is not a full converter like the track converters by Dave Noonan. It's really more a suplement to both N3 Sandbox and those converters.
Let's start by describing what you need to do to convert a GPL track to N3, then we will move on to making them work for ICR2, which needs some more work.
[You will need GPL2TRK, the GPL2N3 converter. Depending on which problems you encounter you might also need the N3 Sandbox, Winmip the Ins2Ope toolkit, an image editor and GPLdef]
Converting GPL tracks to N3:
Everything that we do in this part of the tutorial is needed for the ICR2 conversion proces as well, it is not for N3 only.
1. Install the GPL2N3 converter if you don't have it installed already.
Now I need to explain some things to you. The GPL2N3 converter converts a lot of the GPL track files to N3 by taking the file, doing something to it to make it work in N3 and then copying it into the new N3 track. But there are some files that do not get treated that way. Instead, they have been made in advance, reside in the GPL2N3 folder and are copied into the track during the conversion proces. Examples of those files are the <track>.txt file, the .lp files and the <track>.trk file. This last one is very important, because as you know by now it holds all the physical data of the track. So that is the reason why you can only use the converter to convert a preset list of tracks and no other. Or can you ?
2. Rename the GPL track that you want to convert to N3 to one that the converter can convert. Let's assume you pick Silverstone so you need to rename the track to Silver. Backup that track first of course ! Renaming the track is done by renaming the <track> folder, <track>.dat and the <track>.trk, <track>.3do and <track>.cam inside the <track>.dat. When you use DooDAT you do not have to unpack the .dat file, just open the <track>.dat with it, locate the .cam, .3do and .trk files and rename them.
3. Now run the GPL2N3 converter, select the track that you renamed your new track to [Silver] and hit convert. Then select Convert to N3 and the track will be converted.
Now you have a track in your N3 folder called Silver that is your new track. Except for the .trk file which will be a Silverstone .trk file, as well as the rest of the files I told you were not converted but copied. The .lp files and the <track>.txt for example. But ALL the other tracks were converted and are good to go for N3 ! That means all graphical data is now in place. All you need is the .trk file at this point and that is where the GPL2TRK Tool comes in:
4. Download the GPL2TRK Tool from this site, it can be found in The Archive -> Tools. Now extract to a folder on your hard drive.
5. Go to your version of the track in GPL, the one you ran through the converter. Copy the <track>.trk file and paste it into your GPL2TRK folder. Now you can use the gpl2icr2.bat file to convert the GPL .trk file to the N3/ICR2 format. The .bat file will assume that your GPL .trk is called gpl.trk, the new .trk will be called icr2.trk. If you have problems converting a certain .trk you can open up the Setup.ini that is in the GPL2TRK folder, it contains some flags that you can set. Playing with them can sometimes help you get a better .trk to work with.
Right, so now you have your .trk file. When you are a N3 editor, just dump it into the N3 converted track and test it. Only in testing mode though, because those .lp files are still the ones for Silverstone and will not work in this track causing odd AI behaviour or even game crashes. You will also need to make a new <track>.txt file of course, but other then that the track should work now.
I tried the above proces once with Watkins Glen 1970 and it worked beautifully, the .trk needed no work whatsoever. So the above method can be very rewarding. But I also tried it with St Jovite and then there was an invisible wall right in the middle of the track. When that happens you can try going back to step 5 and change some parameters in the Setup.ini file to see if that gets rid of the problem. If it does not cure it sufficiently, you will need to edit the .trk file.
Editing the .trk:
A. Copy the icr2.trk that you got in step 5 to the folder where you have the trk2sg tool installed and run trk2sg.exe on the file to get an .sg that you can then edit in SGE/SFE. If you can not remember how to use trk2sg.exe, then refresh your memory with tutorial 12.
Unfortunately for us, GPL tracks often have more detail in them then the .sg file format can store. The tool will tell you "SG FILE SUPPORTS TOO FEW SURFACES". Then you will need to edit the GPL .trk file before converting it. In that case the GPL <track>.trk file will need to be edited before converting it to a N3/ICR2 .trk. We will do that with GPLdef.
B. Install GPLdef [found at www.simcyberworld.com].
C. Start GPLdef and choose TRK > Decompile, then browse to the GPL .trk file that you want to edit. The folder selected in the Set Working Directory box is where your .def file will end up.
D. Open the .def file with your .txt edit tool of choice. I like the simplicity of Windows Notepad but usually the file is too big for it so I just use my copy of UltraEdit.
All that data that you see is the .trk data in .txt format. Unfortunately here is where my knowledge about this proces ends. Sander has done this in the past so you can try bugging him to write up something to go here.
Converting GPL tracks to ICR2:
For some reason, the N3 versions of the GPL converted tracks do not convert properly to ICR2. There is probably some data missing that ICR2 needs to run it. This means that for the track to work in ICR2 we need to rebuild the track using N3 Sandbox. But because of Ins2ope this should not have to take long. I will assume you have a working .trk file already, either straight out of the GPL2trk converter or edited with SGE/SFE.
1. Build a .3d from the .trk and a .3do from the .3d file using the N3 Sandbox tools.
2. Open the N3 <track>.3do in 3doEd and use the List Inserts option, then convert the inserts.txt to ope.txt with the Ins2Ope toolbox. If you are not sure how to do all that, then refresh your memory with tutorial 13.
3. Copy all of the N3 track files [.3do/.mip/etc] to your OPE folder, along with the newly built .trk, .3d and .3do files. Then start OPE and load the TSO's by pressing F1 > 3 and typing the name of the ope.txt file.
4. Do any other work that you might want to do in OPE [for example putting in some TSD's, loading additional objects or moving them around]. Then save the track as a .3dn file.
5. Rename the .3dn to .3d and use 3d23do.exe to build a new .3do file.
6. Copy the <track>.3do and <track>.trk to the N3 track and convert it to ICR2. Do not forget to take out the MRON sections in the .3do's first. There will not be a lot, indications are that the GPL2N3 converter was actually designed to build N2 format .3do files, which means that most of the objects do not even have an MRON section in them.
After conversion you will have an ICR2 version of your GPL track ready to be raced. Again, as with N3, the .lp files are still missing and you will need to add things like camera files and some good looking track screens. So if at this point you have a working track move on to the tutorials that describe those files and how to make them.
Problem solving:
However, sometimes during the conversion proces the N2 to ICR2 Converter will crash. If it does that do not click Close on the error screen just yet because it will delete all of the files that it did convert properly, instead:
A. Go to the track in your ICR2 tracks folder that the converter was building. You should see a lot of .3do and .mip files. Make a new folder here called Temp and copy all of the files to it. Then click Close on the N2ICR2 Converter error screen. Copy any .stg, .txt and .lp files to the normal track folder and leave all of the others in the Temp folder.
I am going to assume you took out all of the .3do's MRON sections correctly, which means that the problem lies with the .mip files. Some of them are in a different form then the converter expects them to be. This is how I solve that :
B. Use Winmip to convert all of the N3 .mip files to .bmp. Make sure to have the N2 and Sunny options selected when you use Winmip 1 or that you have the right game selected when using Winmip2.
C. Start your image editor [I use PSP so will tell you how to do this part with that program in mind] and browse to the Temp folder, then open the sunny.pcx file. Save the palette as a .pal file.
D. Again, in your image editor, open all of the N2 .bmp files and for all of them load the .pal file with the ICR2 color palette. Close and save them all.
E. Again, using Winmip, convert all the .bmp files to .mip. This time you should save them in the ICR2 format.
F. Copy all of the newly created .mip files to your ICR2 track's Temp folder.
G. Pack this folder into a .dat and you should have a working track.