处理基于像素的Android游戏的不同分辨率

Question

I am developing a 2D platformer game for the android platform, so I don't really care about the screen DPI, but much more about the actual resolution in pixels. From what I've gathered on the net, there are a couple of different resolutions (and aspect ratios) present. According to my search, the two resolutions that are currently widespread are 480x320 (1.5) and 800x480 (1.666), is that right? I'd like to target these two resolutions to reach most customers. Now, I can deal with the different aspect ratios by showing a black border of 40 pixel for the bigger display, essentialy reducing it to 720x480 pixel and a ratio of 1.5.

The problem with my game is that it is essential for gameplay that the players see the same amount of the world on each screen. Otherwise, some players would get an unfair advantage. Furthermore, I trigger some events depending on the visibility. For example, an enemy is only allowed to start shooting when the player starts seeing it. Otherwise, the enemies' bullets would seem to come from nowhere.

So I figured I need to either create my graphics for one resolution and scale them for the other. Or I create separate graphics for each resolution. Is that right? Unfortunately, both ways are suboptimal for pixel graphics.

On another note: How can I restrict my game to these resolutions only (especially for the Android Market)? I know about the "supports-screens" tag in the manifest, but that works depending on the effective screen-size, not the size in pixel, or am I mistaken? I am also interested in personal experiences of other android game developers when it comes to resolution independence.

Thanks!

Answer 1

My question would be: what do you think would do on a PC? For game development, Android should be looked at much more like a PC target than a console. You just intrinsically need to accept that there will be some diversity of screens that you can't totally predict up-front.

So I think there are two main approaches to take:

(1) Use a constant "display size" as if you were setting a fixed video resolution on the PC and letting the user's monitor deal with it. On these devices of course there is no monitor, just one fixed display, so it doesn't make sense to modify the core resolution. Instead, you can set up the SurfaceView showing your game to have a fixed resolution, and let the platform's compositor take care of scaling it (in hardware) as it composites to the screen.

(2) More intelligently adjust to the actual resolution of the screen you find yourself running in. Scale up or down graphics yourself to create the playing area you want. Maybe have some different sizes of textures and select the appropriate ones for the screen resolution.

You could probably also do a combination of these, where you have a couple fixed sizes you pick for the surface view depending on the total resolution available which the game can run well with. In either case, you can do letter-boxing as appropriate to keep your aspect ratio constant on different screens, if that is what you want.

Answer 2

There are three approaches to differences in aspect ratio:

1. Show opaque borders on some ratios ("letterboxing").
2. Show more of the game world on some ratios.
3. Don't work at all on some ratios.

With approach (1) you waste screen space on some devices. Not such a big deal for televisions, but miserable on handheld devices where screen space is limited. With approach (2) players on some devices get advantages (they can see more of the world) and disadvantages (sprites are smaller, so touch precision is harder). Approach (3) just sucks.

Obviously it depends on the details of your game which is better, but as a player I much prefer approach (2). The constituency who care if players on other devices get a bit of a hypothetical advantage is pretty small compared to the constituency who care if their screen is partly obscured by unnecessary black bars.

(Similar approaches and remarks apply to differences in resolution.)