[vtk-developers] PNGWriter now writing out a black background after 17 Oct.

[Andrew Maclean]

David,

What you are seeing in the Mac is what I see in Windows and what I would
expect.

On Kubuntu 16.10 I get the attached RGBA image - trasnparent with a few
scattered pixels.

if I comment out def testWIFRGB(self): in the code, I get an RGBA with a
blue background (I expected a transparent one). In other words it's the
same as the RGB image. Interestingly, when I was running Unbuntu I got this
image instead of the Kubuntu version.

Attached is the output from running the program in Kubuntu 16.10.

Andrew

On Fri, Nov 11, 2016 at 1:24 AM, David E DeMarle <dave.demarle at kitware.com>
wrote:

> In the RGBA version the blue background _should_ be invisible. The
> question in my mind is why doesn't your Linux build not show anything in
> the foreground? Can you share the png's made by your ubuntu build?
>
> On my Mac for example, for both GL1 and GL2, RGB has a blue background,
> RGBA's is transparent.
> That is expected. The image contents are the same at every pixel except
> that the RGBA'a alpha channel has value 255 for foreground and 0 for
> background pixels.
>
>
> David E DeMarle
> Kitware, Inc.
> R&D Engineer
> 21 Corporate Drive
> Clifton Park, NY 12065-8662
> Phone: 518-881-4909
>
> On Wed, Nov 9, 2016 at 5:18 PM, Andrew Maclean <andrew.amaclean at gmail.com>
> wrote:
>
>> Hi Guys,
>>    For me this still appears to be the case. Try running the attached
>> test code.
>> In Windows and Linux, TestWIFPNGRGB.png are the same.
>> In Windows TestWIFPNGRGBA.png has a transparent background, whilst in
>> KUbuntu no image is produced just a transparent background.
>>   Are you able to replicate this behaviour?
>>
>> Andrew
>>
>> On Wed, Nov 9, 2016 at 10:22 PM, David E DeMarle <
>> dave.demarle at kitware.com> wrote:
>>
>>> Andrew, does this still appear to be the case in the 7.1 release branch?
>>> If so mind filing a quick issue on gitlab with the 7.1 milestone tag?
>>>
>>
>>
>>
>> --
>> ___________________________________________
>> Andrew J. P. Maclean
>>
>> ___________________________________________
>>
>
>


-- 
___________________________________________
Andrew J. P. Maclean

___________________________________________
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