Nicer (& fixed up) help texts for space views

[Wumpf]

Introduced a little utility for this purpose. Not very well-rounded, but a good starting point I like to think :)

Help texts for different space views:

3D:

2D:

Bar chart:

Time series:

Checklist

• I have read and agree to Contributor Guide and the Code of Conduct
• I've included a screenshot or gif (if applicable)

[Wumpf]

on the 3D it says holding alt instead of holding option despite me being on a mac.
emilk/egui#2981 fixes this!

[jleibs]

Would be nice if these semantic constants were shared with the values used here:

rerun/crates/re_viewer/src/ui/view_spatial/eye.rs

Lines 298 to 317 in 78c9936

	pub fn update(&mut self, response: &egui::Response, drag_threshold: f32) -> bool {
	let mut did_interact = false;
	if response.drag_delta().length() > drag_threshold {
	if response.dragged_by(egui::PointerButton::Middle)
	|| (response.dragged_by(egui::PointerButton::Primary)
	&& response.ctx.input(|i| i.modifiers.alt))
	{
	if let Some(pointer_pos) = response.ctx.pointer_latest_pos() {
	self.roll(&response.rect, pointer_pos, response.drag_delta());
	did_interact = true;
	}
	} else if response.dragged_by(egui::PointerButton::Primary) {
	self.rotate(response.drag_delta());
	did_interact = true;
	} else if response.dragged_by(egui::PointerButton::Secondary) {
	self.translate(response.drag_delta());
	did_interact = true;
	}
	}

[Wumpf]

was too lazy to go that extra mile, but yeah at least some of those are pretty easy. Let's put them somewhere central!

[emilk]

that would be nice

[Wumpf]

done that now. Sadly lots of controls are hidden inside other egui constructs like scrollview or plot