wiki

Playfield

The playfield is a portion of the game window where hit objects are placed. On screen resolutions with a 4:3 aspect ratio, the playfield is partially covered with interface elements such as the leaderboard, key counter, or replay controls.

Gameplay

The osu! window (purple) with the playfield (blue), 4:3 aspect ratio.

The osu! window (purple) with the playfield (blue), 16:9 aspect ratio.

The playfield's coordinate system uses resolution-independent units called game pixels, or osu! pixels, such that a game pixel is equivalent to a pixel when osu! is running at a 640x480 resolution. On higher resolutions, the visual size of game pixels stays the same. The playfield is slightly shifted vertically, placed 8 game pixels lower than the window's centre.

The beatmap editor's grid is 512x384 game pixels.

Playfield top left Playfield bottom right Playfield centre
(0, 0) (512, 384) (256, 192)

It is possible to place objects outside the playfield by editing the .osu file in a text editor, or by using automatic stacks triggered by stacking leniency. However, gameplay elements that are at least partially off-screen on screens 4:3 aspect ratio break the ranking criteria.

Note that in the editor, the playfield is scaled down and misaligned to the background compared to gameplay; always look at gameplay when aligning hit objects with the background, storyboard, or video.

Storyboards

The coordinate system used for storyboards has a slightly different origin point, but has the same scale as the playfield coordinate system (i.e. 1 unit has the same size).

Aspect ratio Screen top left Screen bottom right Screen centre In-bounds dimensions
4:3 (0, 0) (640, 480) (320, 240) 640x480
16:9 (-107, 0) (747, 480) (320, 240) 854x480

To convert a position in playfield coordinates to storyboard coordinates, add the offset vector (64, 56), which is the position of the playfield's top-left corner in storyboard coordinates.