No user visible changes expected. The feature is not exposed yet.
For the asset shelf (#102879), design is to use a paginated scrolling
style. That means, that any scrolling will always snap to a multiple of
the page size (the size used when pressing the Page Up/Down keys).
Together with strict region size snapping (implemented in the asset
shelf patch, #104831), this gives a clean scrolling experience where
partially visible rows are avoided (impossible even).
Introduces:
- `View2D.flag` value `V2D_SNAP_TO_PAGESIZE_Y`, which will cause any
scrolling to only use multiples of the page size.
- A custom page size via `View2D.page_size_y` for when the full region
size is not the appropriate page size value.
- API function `UI_view2d_offset_y_snap_to_closest_page()` to enforce
the snapping from outside View2D. The asset shelf uses this to keep
strict scrolling over DPI changes.
Pull Request: https://projects.blender.org/blender/blender/pulls/109154