怎么将go image包的Image转换成vcl.IGraphic实例？ about govcl HOT 15 OPEN

package rotate

import (
	"github.com/ying32/govcl/vcl"
	"github.com/ying32/govcl/vcl/types"
	"image"
	"image/color"
	"unsafe"
)

type rgba struct {
	B, G, R, A uint8
}

type GoBitmap32 struct {
	bmp   *vcl.TBitmap
	cache []uintptr
}

func (b *GoBitmap32) ColorModel() color.Model {
	return color.RGBAModel
}

func (b *GoBitmap32) Bounds() image.Rectangle {
	return image.Rectangle{
		Min: image.Point{
			X: 0,
			Y: 0,
		},
		Max: image.Point{
			X: int(b.bmp.Width()),
			Y: int(b.bmp.Height()),
		},
	}
}

func (b *GoBitmap32) At(x, y int) color.Color {
	var l uintptr
	if b.cache[y] == 0 {
		l = b.bmp.ScanLine(int32(y))
		b.cache[y] = l
	} else {
		l = b.cache[y]
	}
	p := *(*rgba)(unsafe.Pointer(l + uintptr(x*4)))
	rgbaC := color.RGBA{
		R: p.R,
		G: p.G,
		B: p.B,
		A: 255 - p.A,
	}
	return rgbaC
}

func (b *GoBitmap32) Set(x, y int, c color.Color) {
	b.bmp.BeginUpdate(false)
	defer b.bmp.EndUpdate(false)
	var l uintptr
	if b.cache[y] == 0 {
		l = b.bmp.ScanLine(int32(y))
		b.cache[y] = l
	} else {
		l = b.cache[y]
	}
	cp := (*rgba)(unsafe.Pointer(l + uintptr(x*4)))
	c1 := color.RGBAModel.Convert(c).(color.RGBA)
	cp.R = c1.R
	cp.G = c1.G
	cp.B = c1.B
	cp.A = 255 - c1.A
}

func (b *GoBitmap32) Bitmap() *vcl.TBitmap {
	return b.bmp
}

//Free can free the vcl.TBitmap object.
//You can also use 'bmp.Bitmap().Free()' to free the vcl.TBitmap object.
func (b *GoBitmap32) Free() {
	b.bmp.Free()
}

func NewGoBitmap32(bmp *vcl.TBitmap) (goBmp32 *GoBitmap32) {
	goBmp32 = new(GoBitmap32)
	
	if bmp.PixelFormat() != types.Pf32bit {
		panic("not 32 bit bitmap")
	}
	bmp.SetHandleType(types.BmDIB)
	
	goBmp32.bmp = bmp
	goBmp32.cache = make([]uintptr, bmp.Height())
	return
}

l = b.ScanLine(int32(y))
p := *(*rgba)(unsafe.Pointer(l + uintptr(x*4)))
rgbaC := color.RGBA{
	R: p.R,
	G: p.G,
	B: p.B,
	A: p.A,
}
return rgbaC

rgbaC := color.RGBA{
	R: p.R,
	G: p.G,
	B: p.B,
	A: 255-p.A,
}