[vtkusers] remove vtkImageBlend item

[Mauro Maiorca]

Hi David,

sorry, I wasn't clear enough, I'll try again.
Suppose I've got a big image, and I have to add/remove little objects
in just one little area of the image (thus leaving most of the image
as it was). My concern is whether in this particular case it's more
efficient to RemoveAllInputs and add all them again (including the big
image) or removing/re-adding just the little objects (without
removing/re-adding the big image)?

cheers,
Mauro


On Fri, Feb 4, 2011 at 3:13 AM, David Gobbi <david.gobbi at gmail.com> wrote:
> Hi Mauro,
> I'm not quite sure what you mean.  Calling GetOutputPort() doesn't
> cause anything to happen, all it does is return a handle that can be
> used to make a pipeline connection.  Nothing is loaded until the
> pipeline is executed, and even then VTK uses timestamps to make
> sure that the data will only be loaded once.
>  - David
>
> On Thu, Feb 3, 2011 at 8:18 AM, Mauro Maiorca <mauromaiorca at gmail.com>
> wrote:
>>
>> Hi David,
>>
>> thank you very much for your quick reply and your clarification! It
>> makes all sense now, and it works!
>> But, how can I keep track of a particular object, then?
>> I don't mind redrawing all the canvas, but I'm concerned about a
>> reasonably big image (i.e. up to 4096x4096 pixel): I assume each call
>> to blend->AddInputConnection(0,color->GetOutputPort()) will re-load
>> the whole image, unless AddInputConnection has a really smart
>> buffering policy (is it the case?).
>>
>> cheers,
>> Mauro
>