Topic: Advice / help wanted for mapping 3D DOS game with vector graphics

[tetris42]

I'm very interested in mapping the old game "Test Drive III" released on DOS in 1990.  I think the detail of the level design in what's a fully 3D sandboxed world for 1990 is incredible.  Unfortunately I have no programming knowledge and because the game is in 3D, I can't exactly just stitch screenshots together.  My guess is there is maybe two possible approaches to this:

1. The game includes built-in camera controls that let you fly around to some degree.  This includes a camera tilt up / down function, but it stops at maybe a 45 degree angle each way.  If the executable could be modified so that it could look 90 degrees down, I could stitch together screenshots that way by flying around and taking ground shots.  Changing the .exe is definitely possible, in the version of the game I played, somebody already modified it to have unlimited lives.  This method would be tedious and there would be some inaccuracies due to perspective differences of being in 3D, but it's better than nothing.  I was thinking maybe the program Cheat Engine might be able to assist with this.

2. Since the game is in 3D, find some method of having the whole area rendered at an isometric angle, similar to how I've seen some N64 games here.  This would be the ideal method, but unfortunately this would require programming knowledge and experimentation, I simply don't have the skillset or software to do this.


If anyone out there has ideas on how to accomplish either of these methods or is willing to assist, please let me know. I'm very keen on trying to have this game mapped out.

Abandonware link for the game

Sample Screenshots:

[Peardian]

Wow, that is impressive.


I know quite a lot about 3D, but not programming. If anybody with programming skills wants to take up the challenge, I'd be more than happy to help with all of the 3D aspects, such as how to generate models, use them, etc.

[TerraEsperZ]

That would be quite a project if you could manage to do it. I remember making hand-drawn maps of this game decades ago and being surprised when I found out that some tracks would loop around from one side of the map to the other.

Given how old this game is, the 3D is pretty primitive and should be (relatively) easy to decipher IF you have some experience with basic 3d geometry. That unfortunately is not my case , and nobody seems to care about hacking games this old.

All I can contribute is this page I just found that talks about the game and even includes a map of the first track.

[tetris42]

Wow, well that map for the first track is more than I ever found on it.  Even then, there's an incredible amount of details not on it; like farmland patches, sandbars, additional ponds, extensions of some roads / train tracks, a lighthouse, etc.  Thanks for the initial interest, I'm keeping my fingers crossed someone knowledgeable enough will be attracted to this project, even if it is kind of a longshot.

[Maxim]

Hacking the game is unlikely to get you very far, I think. The most likely approach would be to extract the 3D data, but that would be quite hard too, especially without programming or 3D experience.

[tetris42]

Hacking the game is unlikely to get you very far, I think. The most likely approach would be to extract the 3D data, but that would be quite hard too, especially without programming or 3D experience.

Well my reasoning is that if someone else was already able to hack the game enough to change how many lives are given to the player, maybe hacking it to change the limit of the tilt angle when in camera mode (shown in the 2nd screenshot) to 90 degrees down might be doable as well.  It's by no means the preferred solution, but anything else requires programming knowledge, which is I'm guessing will be even more unlikely to get.

[Peardian]

Well, even hacking it to change the camera viewing angle would require at least a little bit of programming knowledge (to know what to look for, change, etc.), but it would certainly be easier than extracting level data. That said, getting 3D data and working with it shouldn't be too hard, if the game is organized nicely enough.

[DarkWolf]

The game engine might not be designed to display an angle of 90 degrees.  Early 3d games use custom software rendering, and the developer might have only made sure the engine worked for the camera angles it was designed for.  It looks like some of the decorations are sprites instead of models, so those will either disappear at a 90 degree angle or could be displayed improperly if the developers never intended for the camera to be at that angle.  It doesn't hurt to try thought, just know you might not get a usable result.

Extracting the 3d data from a game that old might be difficult.  Even if it's stored in a format that's easy to reverse engineer, you'll still have to know how to use that information to recreate a 3d scene.  I tried working with some Quake map files once (un-compiled, not BSP) and they stored brushes as 3d vectors, but who knows what format this game uses.

[tetris42]

You're right, there are sprites used for trees and brush and MAYBE some of the small guard posts like in the center of the first shot (I couldn't tell from in-game), however the vast majority of the content is in 3D, including the road signs.  For example, the sign and house in the 2nd shot are both in full 3D.  So yes, vegetation would probably look off from a top-down perspective, but I consider this a minor thing since I believe almost everything else would be displayed properly.

Also multiple people are saying "who knows" when regarding the 3D model data; if anyone is inclined, by all means download the game and see for yourself how intelligible it is.  It's abandonware now and I included a link to it in the first post.

[Grizzly]

The credits for the game say:
3D Landscaping: Tom Loughry, Cyndi Kirkpatrick, Tomi Quintana, Jerry Pape

So if one could contact, for example, Tom Loughry, it might be possible to find out how (and where) the maps and objects are stored. If he is allowed to talk about that and still knows it after all these years.

Another Accolade game from 1992, Grand Prix Unlimited, uses a tile based editor and from two short tests I made I am confident that the data is also stored with tile references instead of full vector data. The graphics look similar but I don't know if the same engine and data model is used. Could also be totally different. But if Test Drive III uses a tile based option to store the maps, one would need to find out where the single objects like houses, tunnels and mountain parts are stored after getting the map data itself. And then combine all this.

I cannot do any of the needed tasks, I fear. I tried, but I don't understand enough of the materia. If it would be possible to log all file accesses (and the exact number of bytes and offsets read from those files and in which order) via DOSBox, it could be possible to narrow down the exact data that is accessed when loading a new map, but from my few-minute check it looks like the built-in debugger doesn't log these informations.

[tetris42]

Well it's been so long I'm pretty sure the original developers aren't terribly worried about talking about it, whether they remember it though is another matter.  I could definitely email them if I can find contact info at all.

It is sounding like my camera angle idea may be the more viable option, I may make a post in the cheat engine forums to see if there's any insight on trying to isolate the camera angle value.

[TerraEsperZ]

If you manage to change the camera angle, remember that perspective will still distort the map a little. Stitching screenshots of a hill or mountain will get a bit tricky in that they will not line up perfectly with one another.

[tetris42]

If you manage to change the camera angle, remember that perspective will still distort the map a little. Stitching screenshots of a hill or mountain will get a bit tricky in that they will not line up perfectly with one another.

This method would be tedious and there would be some inaccuracies due to perspective differences of being in 3D, but it's better than nothing. 

[TerraEsperZ]

Sorry, didn't read all the way through :s

[Grizzly]

If it's possible to get the game to display a parallel projection (display objects in distance at the same size as near to the camera) combined with an isometric angle, the game could be mapped even with the sprites. Similar to what has been done with the Wolfenstein 3D and Doom maps.
But forums with more people with hacking experience will be a better place to ask. If they can help you, please write back here.