layout_policy.go RawHistoryFolder

1package core
2
3// layoutAxis is a logical navigation axis, independent of rendering.
4type layoutAxis uint8
5
6const (
7	verticalAxis layoutAxis = iota
8	horizontalAxis
9)
10
11func (a layoutAxis) span(r Rect) int {
12	if a == verticalAxis {
13		return r.H
14	}
15	return r.W
16}
17func (a layoutAxis) offset(r *Rect, pixels int) {
18	if a == verticalAxis {
19		r.Y += pixels
20	} else {
21		r.X += pixels
22	}
23}
24
25// layoutPolicy keeps geometry capabilities distinct from workspace navigation.
26// Window state remains owned by Workspace; policies contain no mutable state.
27type layoutPolicy struct {
28	content, workspace layoutAxis
29	equalCells, wraps  bool
30}
31
32// maximizeHides reports whether a maximized column hides the others, so
33// it is a transient state that focus changes undo: fixed overflow. In
34// scroll overflow and cascade it is a lasting state of its column (a
35// cascade band packs a maximized column alone).
36func (p layoutPolicy) maximizeHides() bool { return p.equalCells && !p.wraps }
37
38// workspaceStep is the workspace step a directional focus past the content
39// edge takes along axis: dir when axis is the workspace axis, else 0.
40func (p layoutPolicy) workspaceStep(axis layoutAxis, dir int) int {
41	if axis == p.workspace {
42		return dir
43	}
44	return 0
45}
46
47func (w *Workspace) policy() layoutPolicy {
48	if w.Overflow == OverflowCascade {
49		return layoutPolicy{content: verticalAxis, workspace: horizontalAxis, equalCells: true, wraps: true}
50	}
51	if w.Overflow == OverflowFixed {
52		return layoutPolicy{content: horizontalAxis, workspace: verticalAxis, equalCells: true}
53	}
54	return layoutPolicy{content: horizontalAxis, workspace: verticalAxis}
55}