Isometric vs Perspective Camera

Recently I’ve been experimenting with using an isometric camera for Pawns for the iPhone.

Isometric views have always felt a little cheesy to me, for historical reasons. In the old days it was often used to fake 3D. Since things don’t get smaller as they move further away from an isometric viewpoint, you could use 2D sprites instead of drawing true 3D objects. This was useful when the graphics hardware was only good at drawing sprites. (For example, old arcade games like Q*Bert or Zaxxon painted their 3D graphics this way.)

The iPhone is of course perfectly capable of rendering true 3D. And with Unity I don’t gain any speed just by switching to a isometric view. Even so, the isometric view has a few advantages.

Firstly, the squares near the rear of the board are the same size as those in front, making it easier for the player to place arrows. Pieces in the back are also more visible this way.

I can also optimize the appearance of the 3D pieces. Under perspective it’s hard to make out the crosspiece on top of the king, for example, depending on the angle. In an isometric view the king’s rotation relative to the camera is always the same, whether it is on the left side of the board or the right. So each model only needs to look good from one angle.

This isn’t just a matter of aesthetics, or covering up my mediocre artistic skills. Pawns will not be fun on the iPhone unless each type of piece is instantly recognizable despite the small screen.

For that matter, with care I could improve the graphics by prerendering high-resolution chess models to make 2D sprites. This might improve their appearance- I’ve been having wrestling with lowering the polygon counts without having the pieces look too crappy. (A topic for a future blog entry, perhaps.)

Of course, if I go to billboarded sprites I can’t simply reposition the camera or lights whenever I feel like. And after seeing Pawns in perspective for so many years, I’m having a hard time getting used to the isometric look. Still, I’ll leave it this way for a while longer and see if it grows on me.