[Paraview] Improving the resolution of a wireframe plot

[Moreland, Kenneth]

OK, it sounds like you are referring to the aliasing problem with the
rendering of the lines. ParaView is (should be) rendering the lines at one
pixel width and drawing the lines using an integer step interpolation
scheme (for example, Bresenham's algorithm). The problem is that if you
look close, the lines are often jagged when they are not lined up with the
pixels and have to switch a row or column.

When you say zoom, I assume you mean you save the image and then zoom into
the image. If you zoomed into ParaView's 3D view, the lines would continue
to be rendered at the same pixel width, so the jaggedness would not really
get any better or worse (although they might flicker in ways that are more
noticeable).

Usually if I want to get a nice quality image, I'll render something much
bigger than I really want, then use a simple image editor to reduce the
size back down (using a smoothing algorithm). That, from a signal
processing point, is a good way to reduce the aliasing you are seeing.
(BTW, you may want to also increase the width of the lines to make them
more visible in the final image.)

-Ken




On 9/24/13 1:27 PM, "Colin McAuliffe" <cjm2176 at columbia.edu> wrote:

>Sorry for the confusion. I was not referring to the resolution of the
>mesh itself, but the resolution of the lines in the wireframe. These
>lines appear pixellated, especially when zoomed, which is what I meant
>by offset. Is there a way to improve this? And if so can it also be
>done from a pvpython script?
>
>Thanks
>
>Quoting "Moreland, Kenneth" <kmorel at sandia.gov>:
>
>> The wireframe shows the edges of the mesh so... use a higher
>> resolution mesh. There might be other tricks you could use, like
>> apply a texture to a surface, but that depends on the nature of your
>>  data.
>>
>> Maybe it would help if it was more clear what you are trying to do.
>> I don't know what you mean by offset lines or really see anything in
>>  your image you would want to remove. If you added more lines they
>> would just follow the existing lines until it became too dense to
>> see any of them.
>>
>> -Ken
>>
>> Sent from my iPad so blame autocorrect.
>>
>> On Sep 23, 2013, at 5:50 PM, "Colin McAuliffe" <cjm2176 at columbia.edu>
>>wrote:
>>
>>> Hi all,
>>>
>>> I am using paraview to generate figures of a distorted mesh. I am
>>> using a wireframe representation. Are there options available to
>>> improve the resolution of the wireframe representation to eliminate
>>>  the offset lines as shown in the attached figure?
>>>
>>> Thanks and all the best,
>>> Colin
>>>
>>>
>>>
>>>
>>> --
>>> Colin McAuliffe
>>> PhD Candidate
>>> Columbia University
>>> Department of Civil Engineering and Engineering Mechanics
>>> <MESHE08M28.png>
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>>
>
>
>
>-- 
>Colin McAuliffe
>PhD Candidate
>Columbia University
>Department of Civil Engineering and Engineering Mechanics