Topic: Sonic 3D Blast (Genesis)

[TerraEsperZ]

I first tried mapping this game in 2005, which was nine years ago ! Needless to say, I was nowhere near as good at mapping at the time as I am today (and compared to some, I'm still not that good so don't think I'm on some ego trip) so I gave up after assembling serviceable maps of a few stages that had a lot of areas I couldn't capture.

Anyway, after experimenting with Sonic Advance 2 on the GBA, I decided to see if I could use a modified version of my camera Lua script for this game since Gens-ReRecording also supports Lua. I wasn't as successful as I would have wanted since I was not able to control the camera directly this time; although I found the coordinates for it, trying to change them makes the display super jittery and only shows the sprites at the intended location, with the actual stage graphics being all messed up. I *can* move Sonic himself around freely though along the isometric axes, and since the camera automatically centers on him I can eventually capture the entire map, even if it's harder than by moving the camera vertically and horizontally like on the GBA.

I wasted a lot of time capturing the starting position and orientation of the various enemies and obstacles only to eventually realize that that there's absolutely no consistency there, with enemies of the same type never starting on the same frame of animation as each other. I decided to introduce some order, by only using one or two frames per type of enemy and obstacles and using the closest one as seen in game because otherwise, it would have looked sloppier while being more accurate.

I also decided to use transparencies to add in two hidden paths, one leading to a cannon on the right edge of the stage and another behind the waterfall. Something to note (if you care about such details) is that the graphics of the right path are actually there but are hidden underneath those of the cliff, while there are no graphics for the path behind the waterfall so I had to assemble it by hand based on the space where Sonic can move after hiding the layer with the waterfall.

Finally, I've attached two pictures at the end of this post to show just how much empty space there is on the first map and how much filler I had to add (don't mind the eye-searing purple). At first, I thought I'd leave the map as is but after taking a look at smaller versions of all the maps on another site, I realized I could pretty much extend the map vertically with very little editing. I only had to remove a few tiles on the outer edges that weren't visible anyway.

Green Grove Zone, Act 1:


Green Grove Zone, Act 2:


Green Grove Zone, Act 3:


Rusty Ruin Zone, Act 1:


Rusty Ruin Zone, Act 2:


Rusty Ruin Zone, Act 3:


Spring Stadium Zone, Act 1:

[BumFengShui]

I also made an attempt at this game last summer except I quit simply because I had burnt out on mapping at the time. Anyway I may be able to help you out. Completely by accident I came across an address with Cheat Engine that when frozen allows you to walk freely over everything. The address changes based on the emulator so if you let me know which emulator you're using I will try to find that address once more. I found it in both of these emulators 'gens_kmod_maxim_003' 'Gens11svn341' with Cheat Engine 6.2.

[TerraEsperZ]

That would be awesome! I'm currently using "Gens11svn341" but can easily upgrade to "Gens11svn341" if needed. I just started using "Gens11svn341" after making sure that nothing major had changed so you can use that one.

Of course, you *have* to teach me how you found that address because I've been searching for something like that but I don't know how to use Cheat Engine for anything other than basic memory search.

[Trop]

I remember playing this game.  It looked so futuristic when it came out.  The idea of mapping it never occurred to me but it looks great, way to go.

[BumFengShui]

Unfortunately I found it completely by accident. When I'm searching for an address I usually narrow it down to a couple hundred results, lock them all at once and then just unlock them so many at a time until I find the one I'm looking for.
I was looking for Sonic's Z address (jump height, I think that would be considered Z?) After getting it down to a low enough number of possible addresses I saved them all & locked them while mid jump, after I found my Z address I still had a bunch of others locked which didn't seem to do anything until I started running, I realized 1 of them was letting me go everywhere. It was just pure luck that I found it.

007DFF72  - 2 Bytes
Remember to make a save state before doing this or you could get stuck in purgatory.
Jump and freeze it mid-air without pausing, when you hit the ground you should be free to roam the stage. A few enemies and objects will still be able hit you but you run over or under most of them.

007D47F8  - 1 Byte
Lock the value at 255 to freeze the water animation. (This is the only other address I have saved for this emulator)

Keep in mind I never finished mapping Stage 2 so I don't know if these work past that point.

[TerraEsperZ]

I'm not too concerned with freezing animation as I'm used to moving one frame at a time when capturing them.

In any case, I tried your addresses this morning but they didn't seem to work. I ran into a similar problem with my Makai Toushi SaGa maps for the Wonderswan, where the addresses for the player's coordinates would change every time I restarted the emulator, which happened often thanks to screenshots no longer being saved after exactly one hundred of them. Okay, so I don't know why exactly it didn't work this morning, but it seemed to have something to do with the fact that the address might have been a pointer? In any case, it works perfectly now so thanks a whole bunch!

In any case, I never would have thought to go after Sonic's Z coordinate on my own. I kept trying to see if there was a variable that would change whenever Sonic couldn't move in a particular direction but I guess collision detection is a bit more complex than that.

[TerraEsperZ]

Well it turns out this is going to be even easier than I thought and won't even require Cheat Engine. It just never even came to my mind to simply alter how I calculated Sonic's new coordinates after pressing a key so that he'd move horizontally and vertically instead of diagonally. For example, pressing up to move him on the Y isometric axis would move him upward to the right, so I added an additional move to the left on the X axis which would move him upward and to left, thereby resulting in Sonic appearing to move vertically in respect to the screen. I did that with all four directions and can now move freely around all the maps (old games like that most likely didn't employ dynamic memory addressing so the coordinates are probably always in the same location).

Also, for some reason, the game has stopped glitching where it would it would show a screen telling me I found a special stage every minute or so. Win-win!

[TerraEsperZ]

Updated first post with the map for Green Grove Zone, Act 2.

And just for fun, I'm also including "before" and "after filler" for comparison. This one was messier than the first map, with that big hole right in the middle but I think it ended up looking quite good. The next map is a small boss arena so it should be done quickly.

[TerraEsperZ]

Updated first post with the map for Green Grove Zone, Act 3.

As you can (hopefully) see in the attached thumbnails, there was a river at the bottom of the map but it ended abruptly near the center of the map in such a way that I pretty much had to alter it so it became a waterfall. I'm really happy with the result.

Now, onward to Rusty Ruin Zone!

[alucard]

Great job as usual. So glad this game is getting mapped.

[TerraEsperZ]

I'm almost finished with the next stage but I'm starting to get doubts about using transparencies to denote hidden paths and areas. It just never seems to look right; it's always either too visible, or not enough. I'm experimenting a bit with the final presentation but I'm probably going to do two version of each map, one with the secrets and one without (especially since I want to point out secret warps with big letters). It might not be a great Sonic game or even a good looking one, but I think it deserves to have clean versions of its stages visible for all.

[TerraEsperZ]

Updated the first post with the map for Rusty Ruin Zone, Act 1.

Not much to mention about this map except that there was some visibly bad tiling on the periphery of the map and especially on the right edge, which I corrected. However, it also features a hidden shortcut and a secret passage. I wanted to show them on the map but I really felt that Sonic maps shouldn't be burdened by labels, letters and arrows. Because of that, I've removed the hidden stuff from the previous maps and I'll only add them back on separate maps if/once I find a way to depict them that I'm happy with.

[TerraEsperZ]

Updated the first post with the map for Rusty Ruin Zone, Act 2.

[TerraEsperZ]

Updated the first post with the map for Rusty Ruin Zone, Act 3.

I'm not going to bother with the thumbnails anymore, since I doubt anyone except me is really interested in them. I'm such a geek...

[TerraEsperZ]

Updated the first post with the map for Spring Stadium Zone, Act 1. That one was a real bitch to fill up, what with having to extend all the walls diagonally and all those little round yellow tiles having more variations than you would think. I also made a few corrections to Green Grove Zone, Act 1 (for consistency with later maps, I decided to show both sets of gates near the start as being closed instead of the second set being open) and Rusty Ruin Zone, Act 1 (there were a few errant purple pixels left on the map that were supposed to be black).