You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: loader.go
    path of file: ./repos/caire/vendor/gioui.org/widget/material
    
    the code of the file until where you have to start completion: // 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"
)

type LoaderStyle struct {
	Color color.NRGBA
}

func Loader(th *Th
    
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.Dp(24)
	}
	sz := gtx.Constraints.Constrain(image.Pt(diam, diam))
	radius := sz.X / 2
	defer op.Offset(image.Pt(radius, radius)).Push(gtx.Ops).Pop()

	dt := float32((time.Duration(gtx.Now.UnixNano()) % (time.Second)).Seconds())
	startAngle := dt * math.Pi * 2
	endAngle := startAngle + math.Pi*1.5

	defer clipLoader(gtx.Ops, startAngle, endAngle, float32(radius)).Push(gtx.Ops).Pop()
	paint.ColorOp{
		Color: l.Color,
	}.Add(gtx.Ops)
	defer op.Offset(image.Pt(-radius, -radius)).Push(gtx.Ops).Pop()
	paint.PaintOp{}.Add(gtx.Ops)
	op.InvalidateOp{}.Add(gtx.Ops)
	return layout.Dimensions{
		Size: sz,
	}
}