[vtkusers] vtk.js: display particular cells with alpha/transparency/opacity

[Raimonds Vilums]

https://codepen.io/raimonds-vilums/pen/OrMrEz

After load, you can see colored cells without transparency (3-component
array).

For loading 4-component array, change array name on line 187
from mapper.setColorByArrayName('*rgbData*');
to mapper.setColorByArrayName('*rgbaData*');
which does not work.

Raimonds


On Thu, Dec 13, 2018 at 6:59 PM Sebastien Jourdain <
sebastien.jourdain at kitware.com> wrote:

> Can you do a codepen and share it so I can see what you are doing exactly?
>
> On Thu, Dec 13, 2018 at 9:26 AM Raimonds Vilums <
> raimonds at cenos-platform.com> wrote:
>
>> I tried and got
>>
>> index.js:441 Uncaught (in promise) TypeError: Cannot add property 3,
>> object is not extensible
>>     at Object.publicAPI.rGBAToRGBA (index.js:441)
>>     at Object.publicAPI.convertToRGBA (index.js:487)
>>     at Object.publicAPI.mapScalars (index.js:238)
>>     at Object.publicAPI.mapScalars (index.js:272)
>>
>>
>>
>> On Thu, Dec 13, 2018 at 6:10 PM Sebastien Jourdain <
>> sebastien.jourdain at kitware.com> wrote:
>>
>>> You should be able to have an array with 4 components (RGBA)
>>>
>>> On Thu, Dec 13, 2018 at 9:01 AM Raimonds Vilums <
>>> raimonds at cenos-platform.com> wrote:
>>>
>>>> Hi,
>>>>
>>>> Is it possible to display cells with custom opacity for each cell?
>>>>
>>>> Till now, I managed
>>>> 1) set opacity to the actor (e.g., actor.getProperty().setOpacity(0.5))
>>>> 2) color cells with solid colors, e.g:
>>>>
>>>>
>>>>    - vtk file contains CELL_DATA array of floats with 3 components for
>>>>    every color
>>>>    -
>>>>
>>>>    mapper.setColorModeToDirectScalars();
>>>>
>>>>    -
>>>>
>>>>    mapper.setScalarModeToUseCellFieldData();
>>>>
>>>>    -
>>>>
>>>>    mapper.setColorByArrayName('my_cell_data');
>>>>
>>>>
>>>> But I could not find a way to set alpha/opacity/transparency for
>>>> particular cells.
>>>> Is it possible?
>>>>
>>>> Regards,
>>>> Raimonds
>>>>
>>>> _______________________________________________
>>>> 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/20181214/1747ad71/attachment.html>