Fix #114557: UI scrollbar "focus bubble" interaction wrong in cases #114631

Philipp Oeser · 2023-11-08T14:15:22+01:00

Philipp Oeser commented

2023-11-08 14:15:22 +01:00

Some Editors like the Filebrowser or Spreadsheet set up custom masks for
scrollbars (they dont cover the whole region width or height, some rows
or colums are excluded here -- e.g. the "index" column in the
Spreadsheet), this was working fine for drawing, but mouse interaction
was ignoring these custom masks.

Symptoms were that clicking on the "focus bubble" of the scrollbar and
dragging would not result in smooth scrolling [because internally code
would assume the mouse was clicking outside], instead scroll by 1 'page'
was happening [was perceived as a massive lag]. Especially noticable
with many rows/columns (where the "focus bubble" gets small).

So for drawing (UI_view2d_scrollers_draw) this wasnt a problem, masks
were passed in for view2d_scrollers_calc.
But for interaction (scroller_activate_init) view2d_scrollers_calc
is called again and a NULL mask was passed.

The already set up rects need to be considered though, otherwise coords
for mouse_in_scroller_handle later are not compatible.
To fix this, use existing View2D rects fors scrollbars, and pass a
union of those as mask_custom to view2d_scrollers_calc.

NOTE: this can temporarily extend the View2D scrollbar rect by a
pixel, the next draw call will correct this again though.

Some Editors like the Filebrowser or Spreadsheet set up custom masks for scrollbars (they dont cover the whole region width or height, some rows or colums are excluded here -- e.g. the "index" column in the Spreadsheet), this was working fine for drawing, but mouse interaction was ignoring these custom masks. Symptoms were that clicking on the "focus bubble" of the scrollbar and dragging would not result in smooth scrolling [because internally code would assume the mouse was clicking outside], instead scroll by 1 'page' was happening [was perceived as a massive lag]. Especially noticable with many rows/columns (where the "focus bubble" gets small). So for drawing (`UI_view2d_scrollers_draw`) this wasnt a problem, masks were passed in for `view2d_scrollers_calc`. But for interaction (`scroller_activate_init`) `view2d_scrollers_calc` is called again and a NULL mask was passed. The already set up rects need to be considered though, otherwise coords for `mouse_in_scroller_handle` later are not compatible. To fix this, use existing `View2D` rects fors scrollbars, and pass a union of those as `mask_custom` to `view2d_scrollers_calc`. NOTE: this can temporarily extend the `View2D` scrollbar rect by a pixel, the next draw call will correct this again though.

Philipp Oeser added 1 commit 2023-11-08 14:15:37 +01:00

2f2e566647 Fix #114557 : UI scrollbar "focus bubble" interaction wrong in cases

Some Editors like the Filebrowser or Spreadsheet set up custom masks for
scrollbars (they dont cover the whole region width or height, some rows
or colums are excluded here -- e.g. the "index" column in the
Spreadsheet), this was working fine for drawing, but mouse interaction
was ignoring these custom masks.

Symptoms were that clicking on the "focus bubble" of the scrollbar and
dragging would not result in smooth scrolling [because internally code
would assume the mouse was clicking outside], instead scroll by 1 'page'
was happening [was perceived as a massive lag]. Especially noticable
with many rows/columns (where the "focus bubble" gets small).

So for drawing (`UI_view2d_scrollers_draw`) this wasnt a problem, masks
were passed in for `view2d_scrollers_calc`.
But for interaction (`scroller_activate_init`) `view2d_scrollers_calc`
is called again and a NULL mask was passed.

The already set up rects need to be considered though, otherwise coords
for `mouse_in_scroller_handle` later are not compatible.
To fix this, use existing `View2D` rects fors scrollbars, and pass a
union of those as `mask_custom` to `view2d_scrollers_calc`.

NOTE: this can temporarily extend the `View2D` scrollbar rect by a
pixel, the next draw call will correct this again though.

Philipp Oeser added this to the User Interface project 2023-11-08 14:15:55 +01:00

Philipp Oeser requested review from Julian Eisel 2023-11-08 14:16:05 +01:00

Philipp Oeser requested review from Harley Acheson 2023-11-08 14:16:44 +01:00

Harley Acheson commented

2023-11-10 23:59:22 +01:00

Hey @lichtwerk !

I couldn't figure out how to recreate "clicking on the "focus bubble" of the scrollbar and dragging would not result in smooth scrolling".

But I do see something this fixes, but not sure if this is exactly related or or not. When in Spreadsheet with a size that requires horizontal scrolling, I am not able to click in the area marked with yellow to move to the left.

With your patch applied this works as expected. Is this the thing you are fixing or is there something else to test?

Hey @lichtwerk ! I couldn't figure out how to recreate "clicking on the "focus bubble" of the scrollbar and dragging would not result in smooth scrolling". But I do see something this fixes, but not sure if this is exactly related or or not. When in Spreadsheet with a size that requires horizontal scrolling, I am not able to click in the area marked with yellow to move to the left. ![image](/attachments/25c8a7a5-9662-40c4-bffc-ad8dd4fdebaa) With your patch applied this works as expected. Is this the thing you are fixing or is there something else to test?

image.png

17 KiB

Philipp Oeser commented

2023-11-11 16:56:52 +01:00

What you describe is part of the same problem. Have you tried the file from #114557? (lots more columns)