[vtkusers] How to get the framebuffer

[ling Hai]

Hi Mathieu,
Thank you for the response, I am already calling renderWindow->Render(). I
tried reading the front, back, left and right buffers but am still unable
to get any data from the call. If it helps, I am not using shaders, color
points, or opacity the blending mode is composite, it is rendered by the
gpu.

Linghai

On Wed, Jul 25, 2018 at 3:52 AM, Mathieu Westphal <
mathieu.westphal at kitware.com> wrote:

> Hi LingHai
>
> Make sure you have rendered into the renderWindow first.
> (renderWindow->Render())
> And try to read from the front and the back buffer.
>
> Best regards,
>
> Mathieu Westphal
>
> On Tue, Jul 24, 2018 at 7:57 PM, ling Hai <qyaoza at gmail.com> wrote:
>
>> Hi,
>> I am new to vtk and I am trying to get the front framebuffer from the
>> renderwindow like this:
>> int * dim = renderWindow->GetSize();
>> unsigned char* pixels = renderWindow->GetPixelData(0,0
>> ,dim[0]-1,dim[1]-1,true);
>>
>> but in pixels there is only a null value. I am using this on a 3d render
>> if that makes a difference the above segment of code called after rendering
>> the volume. What am I missing? Any help is appreciated thanks.
>> Linghai
>>
>> _______________________________________________
>> Powered by www.kitware.com
>>
>> Visit other Kitware open-source projects at
>> http://www.kitware.com/opensource/opensource.html
>>
>> Please keep messages on-topic and check the VTK FAQ at:
>> http://www.vtk.org/Wiki/VTK_FAQ
>>
>> Search the list archives at: http://markmail.org/search/?q=vtkusers
>>
>> Follow this link to subscribe/unsubscribe:
>> https://public.kitware.com/mailman/listinfo/vtkusers
>>
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://public.kitware.com/pipermail/vtkusers/attachments/20180725/ce08da64/attachment.html>