I've been reading guides and watching tutorials on YouTube to learn the basics.
Instead of starting with editing/designing levels, I want to learn how to use custom graphics. I want to eventually create a ROM hack that is completely unique with custom images.
A ROM hack that has been very inspiring is "Call of Cthulhu", from the custom title, intro, character sprites, music, etc. It's very unique and one of my favorites.
To begin, I want to change the "Nintendo Presents" logo that appears at the beginning. I've found the sprite map in Lunar Magic, however I would like to use my own image, but also don't want to be limited to a tiny area.
I've applied the patch "Nintendo Presents Logo Expansion v1.3" using ASAR, and imported the included "ExGFXBD.bin" file into the ROM using Lunar Magic, however I don't understand how to apply the imported ExGFX using the "Super GFX Bypass" window to see the new image. I don't know which drop-down to choose, etc.
The GFX bypass options and most other stuff you do in Lunar Magic's level editor only applies to the levels. Since the Nintendo Presents sequence is a special game mode the graphics will need to be loaded in a different way. In this case, it looks like just inserting the ExGFX in the ROM is all you need (assuming you didn't change its number, in which case you'd need to change "!GFX_FILE = $BD" inside the asm file), since the patch will take care of pulling the correct graphics from the ROM.
1) Open ROM "Super Mario World (USA).sfc" with Lunar Magic.
2) Press mushroom buttons to extract images.
3) Place ExGFX file in the newly created folder.
4) Press mushroom buttons to import the graphics.
5) Patch ROM using ASAR.
ASAR responds with "Warning: The ROM title appears to be "☻ΦΦÑû↑}¥²←)≡↑i♥Öⁿ↨Ñùi", which looks like garbage. Is this your ROM title? (Note that inproperly answering "yes" will crash your ROM.)"
I continue, and upon loading the ROM in SNES9X emulator, I see the NORMAL "Nintendo Presents" logo, and then a black screen with no intro.
1) Patch ROM first using ASAR.
2) Load ROM into Lunar Magic.
Lunar Magic responds with "The ROM's checksum has been tampered with, which means the file has either been previously modified by another program or is corrupt. Although Lunar Magic can still open the ROM, it's usually best to use a fresh ROM when first starting out."
3) Use mushroom buttons to extract and then import graphics after including the ExGFX file from the patch.
I keep getting errors about Checksum and file header, etc.
Rename the ROM to .smc, or asar will assume it's headerless (while it's not, since Lunar Magic will add the header the first time you open it) and print that error.
For the checksum error, it can happen but when opening the rom in LM and saving it, it should be fixed automatically.
That worked! Thank you very much! The issue was due to the .sfc file extension. Renaming to .smc was the correct solution.
For a beginner (not to computers or coding), hacking this ROM is difficult. I was able to change the image by copying & pasting some simple pixel art into the ExGFX file, then find out I'm restricted in which colors can be displayed, so none of my colors were correctly represented...