SGDK needs 8BPP, 4BPP, 1BPP

Hello everyone:

This is my first post! I tried searching for this before hand, and if i’ve missed it or perhaps I’m not using the right words to search please feel free to point me to the posting(s). Long story short, i’m doing some Sega Genesis development using the SGDK and when playing around with sprites I get error messages with any of them that I try to use saying that only 8BPP, 4BPP, 1BPP is supported and I keep finding sprite sheets that are 24 or 32bpp format. I’ve even tried opening them up in Photoshop and the mode for the images states that its 8 channel which confuses me.

So, now with the background. I’m looking for a product such as Aseprite that i can build my own sprites but with that photo shop feel; but I need to know when i go to save/export any creation will it support 8BPP, 4BPP, 1BPP?

Thanks again!

Photoshop lists bits per channel rather than bits per pixel. So, in a 3-channel image (RGB, no alpha) that’s 24bpp, and in a 4-channel image (RGBA) that’s 32bpp.

Aseprite does not have bit depth options, AFAIK. You can save in Indexed Color mode, or in RGBA (32bpp) mode.

Unfortunately I’m not aware of any modern image editors that support lower bit depths, but you might be able to find or write a converter for bitmaps, since that format’s fairly simple and the conversion is easy.

Thanks again, I think I eventually figured out a way to make this work. It seems, for the purposes of creating sprites for the sega genesis you cannot do anymore than 16 colors in your palate and you definitely must have your sprite set to indexed.