[vtkusers] Problem with shadows

[abcd efgh]

Hi,

Due to some reason I am not able to attach screenshot.
But if I rotate and change the angle for the Polydata by interacting with
it, I can see colors correctly, only at certain angles the colors are dark
the way you see for shadows. May be my understanding is wrong, meanwhile I
will try to work with Normals ,Scalars. But if there is a way to turn off
every shadow or add lights to all viewing angles it would be great.

Thanks



On Fri, Jul 21, 2017 at 12:12 PM, David Gobbi <david.gobbi at gmail.com> wrote:

> Can you attach a screenshot?  My own experience with VTK tells me that it
> is very, very unlikely that you are seeing shadows.  Whenever I see dark
> areas in VTK rendering, it is almost always due to the scalars, the
> normals, or the winding of the polydata.  It could be that some of your
> polygons are wound incorrectly.
>
>
> On Fri, Jul 21, 2017 at 12:37 PM, abcd efgh <adarshdesai.dsp at gmail.com>
> wrote:
>
>> previously forgot to add VTKusers list.. forwarding same mail.
>>
>> Hi,
>>
>> Thank you for the input. I have tried with new Normals, its the same.
>> I dont think there is an issue with normals. When Poly data appears on
>> screen, it will be in darkness(shadow).
>> I need to turn off every shadow in the renderer. I am using
>> Renderer->UseShadowsOff(), still no use.
>>
>> Please someone guide me to turn off all shadows in the scene. Just like
>> how the Cube source appears in the renderer.
>>
>> Thanks
>>
>> On Thu, Jul 20, 2017 at 3:52 PM, abcd efgh <adarshdesai.dsp at gmail.com>
>> wrote:
>>
>>> Hi,
>>>
>>> Thank you for the input. I have tried with new Normals, its the same.
>>> I dont think there is an issue with normals. When Poly data appears on
>>> screen, it will be in darkness(shadow).
>>> I need to turn off every shadow in the renderer. I am using
>>> Renderer->UseShadowsOff(), still no use.
>>>
>>> Please someone guide me to turn off all shadows in the scene. Just like
>>> how the Cube source appears in the renderer.
>>>
>>> Thanks
>>>
>>> On Mon, Jul 17, 2017 at 12:06 PM, David Gobbi <david.gobbi at gmail.com>
>>> wrote:
>>>
>>>> If it isn't the scalars, then it is probably the normals.  If the data
>>>> has bad normals, then lighting of the data will be incorrect.
>>>>
>>>> You can try generating new normals for the data with
>>>> vtkPolyDataNormals.  Make sure that you read the documentation for this
>>>> class, it has lots of options.
>>>>
>>>>  - David
>>>>
>>>>
>>>> On Mon, Jul 17, 2017 at 12:31 PM, abcd efgh <adarshdesai.dsp at gmail.com>
>>>> wrote:
>>>>
>>>>> Thanks,
>>>>> if  I turn off scalars then I see only white color, by the way even
>>>>> after that I see the shadow effects, how can I turn off the shadows in the
>>>>> scene completely.
>>>>> I think the problem is with respect to shadows.
>>>>>
>>>>> Thanks again.
>>>>>
>>>>> On Sun, Jul 16, 2017 at 5:21 AM, David Gobbi <david.gobbi at gmail.com>
>>>>> wrote:
>>>>>
>>>>>> Clipping a data set adds scalars to the data set. These scalars are
>>>>>> probably causing the strange coloring that you are seeing. You can tell the
>>>>>> mapper to ignore the scalars, and use the vtkProperty color instead:
>>>>>>
>>>>>> mapper->ScalarVisibilityOff();
>>>>>>
>>>>>>  - David
>>>>>>
>>>>>> On Sun, Jul 16, 2017 at 2:15 AM, abcd efgh <adarshdesai.dsp at gmail.com
>>>>>> > wrote:
>>>>>>
>>>>>>> Hello,
>>>>>>>
>>>>>>> I am new to vtk. I have a 3D polydata, I cut it using
>>>>>>> vtkClipPolydata.
>>>>>>> Now there are some shadow kind of thing, I have called functions to
>>>>>>> turn off shadows
>>>>>>> as well as backface culling as off. But still shadow kind of effect
>>>>>>> remains and the Poly data is sometimes dark due to this.
>>>>>>>
>>>>>>> Thanks
>>>>>>>
>>>>>>
>
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