Add another SEGA logo into Wonder Boy V/MW III

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ArcadeTV
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Add another SEGA logo into Wonder Boy V/MW III

Post by ArcadeTV » Tue Dec 04, 2018 12:02 pm

Hi guys,

I started my take on a translation for Wonder Boy V / Monster World III and no problems so far.
This is my latest build: https://www.dropbox.com/s/zj6dlzvoyrzao ... 5.bin?dl=1

My perception of the logo in the title screen is that it doesn't represent the MW identity, so I took the graphics for an upgrade using the same palette and arrangement as seen in the JP version of the game.
eu_us.png
eu_us.png (8.37 KiB) Viewed 1902 times
jp.png
jp.png (8.22 KiB) Viewed 1902 times
>>
new.png
new.png (241.09 KiB) Viewed 1902 times
So far so good and absolutely doable for a asm-rookie like me.

Now it turns out that the US/EU version displays the tiles for the logo in a different arrangement - so tiles I would need to replaced are not filled.
I replaced some tiles with numbers to see how they get arranged by the routine:
https://www.dropbox.com/sh/40luqc99gi1h ... kDx1a?dl=0

I suspect there is a script for this, similar to their text-engine:
While using breakpoints for "reading" in GENS and comparing the DIFF between the US/EU rom and the derivate Turma da Monica na Terra dos Monstros (Brazil) I see something that looks like the right hole to dig, but I don't understand what the bytes do.

Around $1B640 is one block, from $7300 is another that I suspect to be responsible for the arrangement of the title screen.


If you have loaded up my current rom, you'll notice that I replaced the SEGA logo with a nice MW30th Anniversary graphic.
The other thing I would like to accomplish is doubling the sega-logo-routine and changing it to show my graphic after the SEGA and then enter the title screen menu.


If anybody feels like helping me out with this, you might like something in return...
Well, today is the release day of "Monster Boy and the cursed Kingdom" which is the latest addition to the MONSTER WORLD saga.
I'll be happy to buy this game for the system of choice for anybody who helps me solve my problem.

Thanks guys!
Last edited by ArcadeTV on Sun Dec 23, 2018 3:05 pm, edited 1 time in total.

Miquel
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Re: Need help with tile-generator-script in Wonder Boy V/MW III

Post by Miquel » Wed Dec 05, 2018 12:14 am

Script to do something that's done once or twice? why do you believe so? Unless all the game is scripted makes no sense to me.
You can bring back that big cylinder now.

ArcadeTV
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Re: Need help with tile-generator-script in Wonder Boy V/MW III

Post by ArcadeTV » Wed Dec 05, 2018 12:31 am

I'm not an expert, I just try to get along with Gens ShellMod, Exodus and very little IDA. What I see is something similar how the text engine works so I thought it kinda make sense..

I could use a hint or two to understand how the logo is being displayed.

Sik
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Re: Need help with tile-generator-script in Wonder Boy V/MW III

Post by Sik » Wed Dec 05, 2018 4:54 pm

Miquel wrote:
Wed Dec 05, 2018 12:14 am
Script to do something that's done once or twice? why do you believe so? Unless all the game is scripted makes no sense to me.
I mean, I've done it a lot of times when the effort to do it manually was still higher (or more tedious, which is a very good way to get distracted and never finish).
ArcadeTV wrote:
Wed Dec 05, 2018 12:31 am
I could use a hint or two to understand how the logo is being displayed.
There's probably some tilemap stored in the ROM (besides the graphics themselves), likely compressed.
Sik is pronounced as "seek", not as "sick".

ArcadeTV
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Re: Need help with tile-generator-script in Wonder Boy V/MW III

Post by ArcadeTV » Wed Dec 05, 2018 5:12 pm

Sik wrote:
Wed Dec 05, 2018 4:54 pm
There's probably some tilemap stored in the ROM (besides the graphics themselves), likely compressed.
That's the kind of hints I was hoping for. Thanks!
Is there something I could read to understand stuff like that?

Miquel
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Re: Need help with tile-generator-script in Wonder Boy V/MW III

Post by Miquel » Wed Dec 05, 2018 9:23 pm

Sik wrote:
Wed Dec 05, 2018 4:54 pm
Miquel wrote:
Wed Dec 05, 2018 12:14 am
Script to do something that's done once or twice? why do you believe so? Unless all the game is scripted makes no sense to me.
I mean, I've done it a lot of times when the effort to do it manually was still higher (or more tedious, which is a very good way to get distracted and never finish).
Writing a script machine easier than two loops... I'm begging to wander in what planet you are. oh! common you have to tell us! Give us a hint at least: When you look around you what do you see: magma, plasma, water or air?

I have asked them repetly how their programing languages work. Not much success so far, can you help me in this endeavor?
Sik wrote:
Wed Dec 05, 2018 4:54 pm
ArcadeTV wrote:
Wed Dec 05, 2018 12:31 am
I could use a hint or two to understand how the logo is being displayed.
There's probably some tilemap stored in the ROM (besides the graphics themselves), likely compressed.
In those cases could be that having a map is contra productive because it could waste more space than having some repeat tiles, and when compressed those repeated tile become very small.
Instead I would search for:
- the code that copies the tiles to vram
- the code that builds the map on vram OR the one that copies it
that’s a more certain bet.

Edit:
Oh my God! Sik, are you the one who is flashing? Because after this message someone is!
You can bring back that big cylinder now.

ArcadeTV
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Re: Need help with tile-generator-script in Wonder Boy V/MW III

Post by ArcadeTV » Sat Dec 15, 2018 1:02 pm

I just wanted to leave a feedback, with some help we managed to overcome the problems I had rebuilding the tiles for the title-screen.
Also the pointer-table-base for the menu items was extended to 8 instead of 6 chars, while relocating the whole table plus strings.

The only thing left to figure out is how to alter the routine for the sega-logo to display my MW 30th Anniversary screen after that.

I'll keep you updated once I made some progress. Thanks!

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Re: Need help with tile-generator-script in Wonder Boy V/MW III

Post by ArcadeTV » Sun Dec 23, 2018 3:01 pm

Hey guys, I've been struggeling with a thing and hopefully one of you has an idea how to solve this:

Since I changed the gfx for the original SEGA logo to a custom "MW 30th Anniversary" logo, I wanted to add a standalone SEGA logo back into the ROM with some effort..

Here's what I came up with:

I used the the disassembly of "COLUMNS" which I found on rh.net to dissect the sega logo to an 8KB standalone version and managed to change the offset of its EntryPoint to somewhere higher in the ROM. (works)

Then I inserted the binary without the header into my MW3 rom into free space.

I changed the EntryPoint given in the header to the new location and JMP back to the original EntryPoint upon when the Logo finishes (same as when Columns enters the Main Menu or a Button is pressed during the logo) (works)

Now I ran into an issue - the V-interrupt routines of MW3 and COLUMNS are rather different -
I tried to circumvent this by writing a byte to an unused area in the RAM which is set when the programm changes from the logo to the game.
Then I merged both V-int routines, branching them conditionally if this byte is set or not.

The final thing works in MAME, but in GENS I run into an Exception offset where the programm counter hangs.

I suspect it has something to do with a routine that's being written to RAM and executed from there on the columns-side, MW3 on the other hand relies on a word-sized value in RAM $FF8006 which seems to get lost on the way.


If it's not too much to ask for I could really use some help debugging this issue.

These are my files:

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