Wracking my brain over PPU vs Camera size

Unity Engine
1

I’m building a simple retro game based on a game I wrote for the C64 decades ago. I want to use my original graphics, which were 8x8 pixels, and have that map to a modern screen not only so it looks right, but so I don’t run into unintended consequences later.

So imagine the source: Original game was 320x200 pixels. Sprites and tiles were 8x8 each. So that’s 40 tiles x 25 tiles. I set the Game view to 320x200 (8:5 aspect ratio)

I’ve cut up the graphics keeping them at 8x8, and use Point Sampling to keep them crisp. So far so good.

Now, how about Pixels Per Unit and Camera size? It seems the combinations are almost infinite with regard to making the graphics LOOK right, but clearly there are impacts to other things and I want to get it right before I hit a wall.

  • At first I did 24 PPU for the sprites, and set the camera to 4.2.
  • Another alternative is 8 PPU, with camera size at 12.5
  • Or 16 PPU with Camera at 6.3
  • Or how about 100 PPU with Camera set to 1 ??

So which is right? I have read to use 100 PPU to keep physics correct. But Some say to use a different PPU so that 1 unit = 1 “tile”.

Insight and discussion is appreciated.

2

Pixels per unit is exactly that, how many pixels do you want to equal 1 unity unit?

Since you say each tile is 8 pixels, I would recommend using 8 pixels per unit, so that each tile is 1 unit. That way you know that something that is 5 units away is 5 tiles, and that 5.5 units away would be the center of a tile, etc.

It is largely preference, but I believe having PPU that is very low can impact how physics will behave.