### Enumeration

# GdkScrollUnit

since: 4.8

#### Declaration

    enum Gdk.ScrollUnit

#### Description [src]

Specifies the unit of scroll deltas.

When you get `GDK_SCROLL_UNIT_WHEEL`, a delta of 1.0 means 1 wheel detent click in the south direction, 2.0 means 2 wheel detent clicks in the south direction… This is the same logic for negative values but in the north direction.

If you get `GDK_SCROLL_UNIT_SURFACE`, are managing a scrollable view and get a value of 123, you have to scroll 123 surface logical pixels right if it’s `delta_x` or down if it’s `delta_y`. This is the same logic for negative values but you have to scroll left instead of right if it’s `delta_x` and up instead of down if it’s `delta_y`.

1 surface logical pixel is equal to 1 real screen pixel multiplied by the final scale factor of your graphical interface (the product of the desktop scale factor and eventually a custom scale factor in your app).

Available since: 4.8

#### Members

`GDK_SCROLL_UNIT_WHEEL`

  The delta is in number of wheel clicks.

  - Value: `0`
  - Nickname: `wheel`
  - Available since: 4.8
`GDK_SCROLL_UNIT_SURFACE`

  The delta is in surface pixels to scroll directly on screen.

  - Value: `1`
  - Nickname: `surface`
  - Available since: 4.8