Topic: Alien 3 and parallax backgrounds

[Master Bait]

When I tried to map again today I came to the conclusion that, like we mentioned, more of the layers are put in the memory than what's currently displayed. Sadly they can be chopped up and put out of order. It also seemed to me that rather then fluidly updating the layer I inspected, it was given to you in chunks. As if you enter a new area as you progress through the level.
Therefore you're prevented from making the graphics overlap to make sure it's in its right position when putting your map together. You simply have to trust that it is cut at the exact right spot. Of course there's no reason why it shouldn't be cut right where it left off plus you should be able to spot if it wasn't. But that is just not how I've been working so far.

Don't know if I made myself clear. English is not my native language. I can sort of see that what I write myself might sound a bit awkward, but I'm still not able to improve it =S

[Peardian]

At least for bgmapper, the position of the tiles upon first loading the scene is related to the camera. There's a button (9?) that lets you automatically position the tiles in the top left corner of each layer's map as it is in memory (as you'd see in VBA). Each room is (typically) it's own separate room file, so the coordinates will always be relative to the current room and not the level as a whole. I hope that is what you were talking about.

[Trop]

OK seriously, which rooms have these parallax backgrounds?  I've looked through a ton of levels and I can't find them.

[Master Bait]

All of you seem to praise VBA. I should map something using it to see for myself. And hopefully learn something also.

OK seriously, which rooms have these parallax backgrounds?  I've looked through a ton of levels and I can't find them.

Alien 3 on the SNES. Not in the starting corridore but as soon as you enter a door.

[Trop]

Oh, I thought you were talking about something else.  Yeah that can't be fixed with a code because the any code that holds the animation still also causes it to move with you.  Example: 7E002499

BgMapper works great though.  Here's what I made using it and photoshop.  SNES transparencies usually use Linear Dodge.

[Master Bait]

We might misunderstand eachother slightly. Probably because I wasn't clear enough from the beginning. My apologies.

That layer you show us in the picture is another issue and honestly I was thinking of leaving it out.
No, for me the very background is enough hassle.

Hope I can make some sense with my picture.



As you all can see, it is possible to produce a map from this. It's just that I've always used some overlapping to make sure everything is correct.

[DarkWolf]

I'm not sure if the applies to SNES savestates, but back before Maxim made his changes to Gens Kmod, I ripped the Sonic 3 two-player stages by opening the savestate in a hex editor and changing the background color in the video memory.  What I did was make a savestate where I wanted an image, edit the color in the hex editor, load the state while emulation was paused, then took my screen shot.  As soon as I resumed emulation, of course the palette was refreshed so I had to repeat the steps, but it did make it possible to rip these levels.

[Peardian]

Ohhhhh I see. It is entirely possible that the background is actually 1024, making it twice as wide as the loading area. It could also be more. Keep moving to the right and see if you can find the other matching piece to what it started with.

[Trop]

That's the problem?  You should have just said "the background is too dark".  Here try these in regular old ZSNES:
7E0200FF
7E0202FF
7E0204FF
7E0206FF
7E0208FF

[Master Bait]

That's the problem?  You should have just said "the background is too dark".  Here try these in regular old ZSNES:
7E0200FF
7E0202FF
7E0204FF
7E0206FF
7E0208FF

It works perfectly.
I'm sorry. I tried to explain in my very first post. When I said "make the emulator display an obscure color, like pink (or even better, transparent for the output image), as its background rather than black." this is exactly what I was looking for. I just don't know what the emulators can do if you fiddle with them a little. Especially not zsnes since I don't use it.


About this.

Ohhhhh I see. It is entirely possible that the background is actually 1024, making it twice as wide as the loading area. It could also be more. Keep moving to the right and see if you can find the other matching piece to what it started with.

I made another image to show you.

That it's twice as wide seems accurate. So this method can be used to map faster. But again, look where it is cut on the left side. At the exact same spot as it was in my previous picture.
But actually, this is something good too. If you trust it, you won't even have to figure out where the joint is. It is right where you left off.

[TerraEsperZ]

That's the problem?  You should have just said "the background is too dark".  Here try these in regular old ZSNES:
7E0200FF
7E0202FF
7E0204FF
7E0206FF
7E0208FF

Out of curiosity, mind explaining what these codes actually do? What memory values are they actually changing, and do they apply to all games (oh please, oh please, say yes...)?

[Trop]

OK this is how this went.  I realized Bait wanted a background re-coloration code when I tried to make a test map myself.  With the main background switched off you get, like Bait said, a black background.  Unfortunately the black in the background is the same black as the black in the foreground.  So the original outline of the foreground is gone and if you try to move the foreground away from the now black background you tear holes in it.  I've encountered this problem before and the only way I was able to fix it was with a code that changed the background color.

This kind of code isn't easy to find or get right but before when I was confused about what Bait wanted I looked around at all the different levels and I remembered one of the last levels has a background that changes color.  Here's what I did:

Enter password SQUIRREL
Walk forward through door immediately in front of you to wind up in a kind of metalworking area
Note the background fades from dark red to bright red
Begin a 1 byte comparative value search
Return to game, allow the color of the background walls to change, return to cheat search as soon as they do
Select != and click the SEARCH button
Repeat the two previous steps until # OF RESULTS: is 50 or less
put in all codes in with VIEW and ADD then switch them on and off testing each until the background stops changing color
Take a working code, like 7E020471, and set the last two numbers as high or low as they will go 7E020400 or 7E0204FF
If only some of the background has changed look for related codes like 7E020632 and follow the pattern
00  02  04  06  08 all starting with 7E02 and, in this case, ending with FF
If this pattern fails in another level or area just push it further with something like 7E03 or 7E01

Remember with ZSNES codes: 7E** (first four numbers) are the base address, the next two numbers will be the more variable address, and the last two just the amount you want with 0 being the lowest and 255 the highest.

So sorry, these codes are just for this game, but the technique should work for any game.  And if there's no cheat gizmo built unto the program you're using give Cheat Engine a try.

[TerraEsperZ]

Ah, I understand. It's a bit more complicated than I thought, but still workable. I was wondering if you simply weren't doing what the latest VBA-M allows you to do, mainly editing the first color entry in the first (background) layer color palette. It's too bad that this method will not work if the background color never changes anywhere during the game, thus preventing you from finding a changing value.

[Master Bait]

I've started mapping this game for real now, thanks to all of you.
So far, so good.

Oh, I thought you were talking about something else.  Yeah that can't be fixed with a code because the any code that holds the animation still also causes it to move with you.  Example: 7E002499

BgMapper works great though.  Here's what I made using it and photoshop.  SNES transparencies usually use Linear Dodge.

I managed with this aswell. Only difference is that I got the layer from vSnes and I use Paint.NET so the correct blending mode is called "Additive".
Just wanted to add that. This thread has taught me alot and maybe it can even be of use for someone else some time 

[feos]

Hi, I created a thread announciing that this problem for SNES games was solved, now backdrop color is a matter of 1 click.
https://www.vgmaps.com/forums/index.php?topic=1859.0