Commit ac71f3406bb294c83e6ad73ba9661192c9c04b99 | snowbound

author	clover caruso <git@paperclover.net> 2026-09-24 01:09:29-07:00
committer	clover caruso <git@paperclover.net> 2026-09-25 20:26:20-07:00
log	ac71f3406bb294c83e6ad73ba9661192c9c04b99
tree	ec3c4e24b0b11dae1875aa23d98cb1fc1a049389
parent	1a88f66f3e89db9e9b9c016c61f9fdd549b74228
signature	Signed by SSH key SHA256:52mNGHRsVFBDED9IAX5pe+LRWUefqTbxEReunq21QvU

fix: stop scrolling at the topmost and leftmost page content

Scrolling allowed 36 pt of blank page above and left of the furthest
object, so a page like one with an Ivy background image placed at
(-27, -3.6) could be scrolled past its top. OneNote 2010 stops exactly
at the page origin or at the object furthest above or left of it, and
opens the page there. The far edges keep their 36 pt margin.

Assisted-by: claude-opus-5

1 files changed, 3 insertions(+), 2 deletions(-)

crates
- snowbound
  - src
    scroll.rs

crates/snowbound/src/scroll.rs+3-2

...	...	@@ -15,8 +15,9 @@ impl Scroll {
15	15	max[axis] = max[axis].max(rect[axis + 2]);
16	16	}
17	17	}
	18	// OneNote stops at the page origin or the object furthest above or left of it.
18	19	for axis in 0..2 {
19		min[axis] = (min[axis] - 36.0) * viewport.scale;
	20	min[axis] *= viewport.scale;
20	21	max[axis] =
21	22	((max[axis] + 36.0) * viewport.scale - viewport.size[axis] as f32).max(min[axis]);
22	23	}
...	...	@@ -100,7 +101,7 @@ mod tests {
100	101	};
101	102	let scroll = Scroll::new(viewport, [[-80.0, -20.0, 1000.0, 1200.0]].into_iter());
102	103	scroll.clamp(&mut viewport);
103		assert_eq!(viewport.origin, [232.0, 112.0]);
	104	assert_eq!(viewport.origin, [160.0, 40.0]);
104	105	viewport.origin = [-9999.0; 2];
105	106	scroll.clamp(&mut viewport);
106	107	assert_eq!(viewport.origin, [-1272.0, -1872.0]);