func (ir *interpreter) upload_image(name string, img image.Image) error {
var buf bytes.Buffer
err := sprintf(&buf, "image create photo %{}", name)
if err != nil {
return err
}
nrgba, ok := img.(*image.NRGBA)
if !ok {
// let's do it slowpoke
bounds := img.Bounds()
nrgba = image.NewNRGBA(bounds)
for x := 0; x < bounds.Max.X; x++ {
for y := 0; y < bounds.Max.Y; y++ {
nrgba.Set(x, y, img.At(x, y))
}
}
}
cname := C.CString(name)
handle := C.Tk_FindPhoto(ir.C, cname)
if handle == nil {
err := ir.eval(buf.Bytes())
if err != nil {
return err
}
handle = C.Tk_FindPhoto(ir.C, cname)
if handle == nil {
return errors.New("failed to create an image handle")
}
}
C.free(unsafe.Pointer(cname))
block := C.Tk_PhotoImageBlock{
(*C.uchar)(unsafe.Pointer(&nrgba.Pix[0])),
C.int(nrgba.Rect.Max.X),
C.int(nrgba.Rect.Max.Y),
C.int(nrgba.Stride),
4,
[...]C.int{0, 1, 2, 3},
}
status := C.Tk_PhotoPutBlock(ir.C, handle, &block, 0, 0,
C.int(nrgba.Rect.Max.X), C.int(nrgba.Rect.Max.Y),
C.TK_PHOTO_COMPOSITE_SET) // alpha should be non-zero or you may get peculiar slowdowns
// Note: C.TK_PHOTO_COMPOSITE_OVERLAY would overlay an existing image
if status != C.TCL_OK {
return errors.New(C.GoString(C.Tcl_GetStringResult(ir.C)))
}
return nil
}
func (ir *interpreter) upload_image(name string, img image.Image) error {
nrgba, ok := img.(*image.NRGBA)
if !ok {
// let's do it slowpoke
bounds := img.Bounds()
nrgba = image.NewNRGBA(bounds)
for x := 0; x < bounds.Max.X; x++ {
for y := 0; y < bounds.Max.Y; y++ {
nrgba.Set(x, y, img.At(x, y))
}
}
}
cname := C.CString(name)
handle := C.Tk_FindPhoto(ir.C, cname)
if handle == nil {
ir.eval("image create photo ", name)
handle = C.Tk_FindPhoto(ir.C, cname)
if handle == nil {
return errors.New("failed to create an image handle")
}
}
C.free(unsafe.Pointer(cname))
block := C.Tk_PhotoImageBlock{
(*C.uchar)(unsafe.Pointer(&nrgba.Pix[0])),
C.int(nrgba.Rect.Max.X),
C.int(nrgba.Rect.Max.Y),
C.int(nrgba.Stride),
4,
[...]C.int{0, 1, 2, 3},
}
status := C.Tk_PhotoPutBlock(ir.C, handle, &block, 0, 0,
C.int(nrgba.Rect.Max.X), C.int(nrgba.Rect.Max.Y),
C.TK_PHOTO_COMPOSITE_SET)
if status != C.TCL_OK {
return errors.New(C.GoString(C.Tcl_GetStringResult(ir.C)))
}
return nil
}