Golden Sun Hacking Community

Golden Sun Games => Golden Sun: The Lost Age => Topic started by: Plexa on October 05, 2017, 06:43:13 PM

Title: The Magic River
Post by: Plexa on October 05, 2017, 06:43:13 PM

So this is a thing.

Frostfx made this convenient image to help explain the glitch:

Title: Re: The Magic River
Post by: Fox on October 06, 2017, 12:06:52 AM
Not exactly a "river," if going by the graphics, but that looks amazing!

:Alex:  Continental shelves are shifting!  And in an unexpected way, no kidding!

I feel like I want to call it The Magic Roundabout. (Referencing a UK cartoon, I think.) ... (And also secretly references something I was part of on RuneScape years ago. :P A clan I joined was named Skilling Central, and they changed their name to The Magic Roundabout, eventually, the clan "died", and owner moved on to another clan: The Round Table. (King Arthur reference, I assume.) I also followed, and that clan is still here today... Though, I haven't been on RS much lately.... I do want to eventually get back to it, but I was planning to hold off until AT LEAST the release of the bank rework. :/ )


Seems to be a 16-pixel margin? 0x1F00-0x1F0F

Map when not scaled is 0x2000px x 0x2000px, I think... but with the scaling, likely doubled... (Referring to current x and y location, since the top of the screen is shorter/bottom is longer.)... so 0x1F00 being right under the half way mark is interesting... (I feel like some rounding thing could be going on... like adding 1 when a number is negative, but I have no idea. Can probably look into it, though. Expecting it to be as simple as a breakpoint write on tilemap ram data. *crosses fingers*)

But first:  Going left/right with Map view open... (using auto-update).... And I'm not sure I understand this...  (Attachement... the column in the middle/at the bottom... when I walked left.) Did not need an encounter to see this... (But I imagine if it is the same as the glitch above.. then you probably would need one to "abuse" it?)
(Also see the same "flickering" on the left side when going right. (First column in map view.))

Almost forgot:  I should test it without messing up the flags... sso this is with messing up storybook flags.... in case it doesn't happen in cannon.

Title: Re: The Magic River
Post by: Atrius on October 07, 2017, 10:44:00 PM
He's correct about the map being split up, but the sections are 256x256 pixels, or 16x16 tiles that are 16x16px.  I don't know what's happening with this glitch beyond that.

FYI there's a full rip of TLA's world map as stored in the game data (except some tilesets are incorrect) available here ( (8192x8192px, 10.8MB)

I could understand why the graphical glitch might happen because of how the graphics rendering is optimized (see Fox's post above), but the fact that the collisions are incorrect too baffles me.

Title: Re: The Magic River
Post by: Fox on October 08, 2017, 06:45:15 AM
@FYI: That's cool, but a lot of those tiles are incorrect. (Since the tileset is switched.) ... Um? Not sure why the link sometimes doesn't work? Says it contains errors. Might be due to memory, though.

Anyway: From gsmagic (At least my version.):  ... (Prox/Mars Lighthouse area.... Gaia Falls... Snow areas... etc.)
Looks like I got some tiles wrong! (I lack water where it is needed.)  Thank you for posting that link!!
(I think I might know why.....) Fixed: (And yes, some of the water tiles are snow in the second huge segment = That is correct. It'll look like water when you're off those tiles, though.)

I know there's a collision tileset (Just for World Map.),... so isn't the indexes that are used for graphics also used for that tileset too? So that would kind of make sense... However, I kind of forgot what I researched a long time ago, so....

World Map tilemap is pasted at 02020000. (Instead of 02010000 as normal maps do.) - 4 square maps are loaded at a time.
zz = Can effect the tileset used.
yy = Event ID
xxxx = Graphical index , but also collision index?(Not confirmed?) (World Map only?) (May not necessarily be 16-bit, but for example...)

Update:  Been too lazy to put that breakpoint in. :/ (It's possible I may even have the function already documented, even if I don't have its contents documented.)

Title: Re: The Magic River
Post by: Plexa on October 13, 2017, 08:49:37 PM
Thanks for the map Atrius. Having explored that area using the first flight cutscene glitch its really cool to actually see what is there :)

But your map also reminded me that there is another point in the game where the overworld is updated - after you fix the boat and set Briggs free.

Getting an encounter with y-coordinate as indicated in the image will cause the bridge to un-fix itself (EDIT: its actually way more lenient, there's a large band of y values than work south of where I am standing). I can't see any other errors caused in this occurrence of the glitch. Of course, opening the menu and closing it again will fix the bridge - as illustrated in this gif:

I guess then the next question is this - when Venus lighthouse is lit at the start of the game, are those cutscenes happening on the copy of gondowan far to the west of the world map? Or is it happening within the world map but having tiles updated?

Title: Re: The Magic River
Post by: Fox on October 14, 2017, 09:30:04 AM
Attachment: An image showing where a flag check is done, and how two map sections (side by side) are copied over. (For the Contigo area.)

In map code initialization....

Arguments: srcx, srcy, desx, desy
No size values or anything, so the whole square (16x16 tiles) should be "copied" over...  By putting a file number in the 03001448 list.

Calls a function that hasn't really been documented, but is in an expected area.


r6 = 02032640 = screen x
r7 = src position
r12 = 02032648 = screen y

to be continued?

Not sure where glitch occurs yet, but I now at least have something about this function in my doc.