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Galaga - Breaking the 8 sprite limit

Galaga - Breaking the 8 sprite limit
by on (#200565)
Hi everyone!

This is my very first post of what will hopefully be many!

I've just started NES development and I'm learning all of the system's quirks and limitations.

I was just playing through a bunch of games on my NES Classic to see how certain things are done and I noticed that Galaga has WAY more than 8 sprites per scanline and there is no flicker!

How is this achieved? My first guess is background tiles. Am I right?

Anyway, I'm currently working on a side scrolling shooter - sequel to my first ever game that I released on iPhone back in 2010 and I have to say working on NES is way more fun!

Cheers!
Re: Galaga - Breaking the 8 sprite limit
by on (#200566)
mantanz wrote:
I was just playing through a bunch of games on my NES Classic to see how certain things are done and I noticed that Galaga has WAY more than 8 sprites per scanline and there is no flicker!

How is this achieved? My first guess is background tiles. Am I right?


Run the game in an emulator with a PPU debugger and you'll see that the enemies are only represented by sprites while they're flying around - once they're in formation, they become part of the background (which is why they don't move as smoothly).

You'll also see that the stars scrolling by in the background are also sprites.
Re: Galaga - Breaking the 8 sprite limit
by on (#200569)
Ha! Why didn't I think to do that? Probanly because I've done everything in Unity for the last 7 years. lol. Thanks!
Yeah the movement is what made me think it was background tiles. Pretty clever trick!
I think the most fun thing about NES dev is dealing with its limitations.