[vtk-developers] Volume rendering update

[Aashish Chaudhary]

Hi David

On Tue, Feb 23, 2016 at 12:02 PM, David Gobbi <david.gobbi at gmail.com> wrote:
> I was playing with the Medical4 example last week, and
> vtkGPURayCastVolumeMapper managed to render shaded volumes at up to
> 1024x1024x768!  Very fast loading, too, it took around 1 second to load.

Great, thanks.

>
> With the volume size at 1024x1024x1024, however, there was a wrap-around
> artifact.  I'm guessing that it was due either to memory limitations, or due
> to integer overflow.  Maybe a hardware issue, maybe the driver, hard to say
> when the data set itself is 2GB.  This is a Mac (10.9.5) with AMD FirePro
> D700 6GB, what datatypes does the mapper use for the buffers?

this is interesting hard to say what's happening here but I didn't
encounter this issue before. Typically I would expect that you get GL
error or a CRASH.
Would be it possible to post your example code and data somewhere? Or
else, I will see if I can create a example myself.

>
> On Tue, Feb 23, 2016 at 9:43 AM, Aashish Chaudhary
> <aashish.chaudhary at kitware.com> wrote:
>>
>> Hi all,
>>
>> We have made some significant improvements to volume rendering since our
>> last update (Ref:
>> https://blog.kitware.com/volume-rendering-enhancements-in-vtk/,
>> https://blog.kitware.com/volume-rendering-on-ios-and-android/). Below is a
>> list of tasks that are either nearly completed and or are in VTK master as
>> of today.
>>
>> Features/updates
>>
>> Big volume support - Fixing failing tests. The idea is to split volume
>> into smaller volumes and render them piecewise.
>>
>> 3x-5x clipping plane performance - For the same parameters, clipping is
>> much faster now, the trick is to skip voxels that are clipped by planes.
>>
>> Depth and color data capture - User can use RenderToImage to render to a
>> FBO and get depth and color texture which then could be utilized for other
>> operations.
>>
>> Bugs
>>
>> Fixed gradient opacity not working for more than one components
>>
>> Fixed clipping plane location is wrong in certain cases.
>>
>> Fixed volume rendering invalid or bad for cell data
>>
>> Fixed edges issue when rendering in multiple pieces (hard edges)
>>
>> Fixed volume rendering not working in remote rendering mode with image
>> reduction factor > 1
>>
>> Fixed volume rendering not working in client-server mode
>>
>> Fixed volume disappears when changing parameters
>>
>> Fixed volume rendering not using the correct sampling distance
>>
>>
>> --
>> | Aashish Chaudhary
>> | Technical Leader
>> | Kitware Inc.
>> | http://www.kitware.com/company/team/chaudhary.html
>
>



-- 
| Aashish Chaudhary
| Technical Leader
| Kitware Inc.
| http://www.kitware.com/company/team/chaudhary.html