mirror of
https://git.sr.ht/~eliasnaur/gio
synced 2026-07-01 07:35:40 +00:00
Elias Naur
94d242d18c
PaintOp.Rect is the wrong abstraction; it implies a clip operation better handled by package clip, and not all paints need it (colors). Furthermore, it's awkward to specify a PaintOp that fills up the current clip area, regardless of its size. Redefine PathOp to mean "fill current clip area". API change. Replace uses of PaintOp.Rect with a TransformOp applied before the PaintOp. Leave a TODO for the PathOp infinity area. Fixes gio#167 Signed-off-by: Elias Naur <mail@eliasnaur.com>
91 lines
1.8 KiB
Go
91 lines
1.8 KiB
Go
// SPDX-License-Identifier: Unlicense OR MIT
|
|
|
|
package material
|
|
|
|
import (
|
|
"image"
|
|
"image/color"
|
|
"math"
|
|
"time"
|
|
|
|
"gioui.org/f32"
|
|
"gioui.org/layout"
|
|
"gioui.org/op"
|
|
"gioui.org/op/clip"
|
|
"gioui.org/op/paint"
|
|
"gioui.org/unit"
|
|
)
|
|
|
|
type LoaderStyle struct {
|
|
Color color.RGBA
|
|
}
|
|
|
|
func Loader(th *Theme) LoaderStyle {
|
|
return LoaderStyle{
|
|
Color: th.Color.Primary,
|
|
}
|
|
}
|
|
|
|
func (l LoaderStyle) Layout(gtx layout.Context) layout.Dimensions {
|
|
diam := gtx.Constraints.Min.X
|
|
if minY := gtx.Constraints.Min.Y; minY > diam {
|
|
diam = minY
|
|
}
|
|
if diam == 0 {
|
|
diam = gtx.Px(unit.Dp(24))
|
|
}
|
|
sz := gtx.Constraints.Constrain(image.Pt(diam, diam))
|
|
radius := float64(sz.X) * .5
|
|
defer op.Push(gtx.Ops).Pop()
|
|
op.Offset(f32.Pt(float32(radius), float32(radius))).Add(gtx.Ops)
|
|
|
|
dt := (time.Duration(gtx.Now.UnixNano()) % (time.Second)).Seconds()
|
|
startAngle := dt * math.Pi * 2
|
|
endAngle := startAngle + math.Pi*1.5
|
|
|
|
clipLoader(gtx.Ops, startAngle, endAngle, radius)
|
|
paint.ColorOp{
|
|
Color: l.Color,
|
|
}.Add(gtx.Ops)
|
|
op.Offset(f32.Pt(-float32(radius), -float32(radius))).Add(gtx.Ops)
|
|
paint.PaintOp{}.Add(gtx.Ops)
|
|
op.InvalidateOp{}.Add(gtx.Ops)
|
|
return layout.Dimensions{
|
|
Size: sz,
|
|
}
|
|
}
|
|
|
|
func clipLoader(ops *op.Ops, startAngle, endAngle, radius float64) {
|
|
const thickness = .25
|
|
|
|
var (
|
|
outer = float32(radius)
|
|
delta = float32(endAngle - startAngle)
|
|
|
|
vy, vx = math.Sincos(startAngle)
|
|
|
|
pen = f32.Pt(float32(vx), float32(vy)).Mul(outer)
|
|
center = f32.Pt(0, 0).Sub(pen)
|
|
|
|
p clip.Path
|
|
)
|
|
|
|
p.Begin(ops)
|
|
p.Move(pen)
|
|
|
|
// Outer arc.
|
|
p.Arc(center, center, delta)
|
|
|
|
// Arc cap.
|
|
pen = p.Pos()
|
|
cap := pen.Mul(1 - thickness)
|
|
p.Line(cap.Sub(pen))
|
|
|
|
// Inner arc.
|
|
center = f32.Pt(0, 0).Sub(p.Pos())
|
|
p.Arc(center, center, -delta)
|
|
|
|
// Second arc cap automatically completed by End.
|
|
p.End().Add(ops)
|
|
}
|