[vtkusers] Volume data from application memory

[Vidyadhar]

Hi
You can create an instance of vtkImageData. Call SetOrigin, SetSpacing 
methods as appropriate (or leave them at their default values). Call 
SetDimensions(nX,nY,nZ) where your buffer dimensions will go (85x54x44). 
Call SetNumberOfScalarComponents (I think you have only one component). Call 
SetScalarTypeToXXX method (matching your buffer type). Now invoke 
AllocateScalars method. Call GetScalarPointer() (void argument) and typecast 
the returned pointer to your buffer data type. Now you can copy memory from 
your buffer to the buffer allocated by vtkImageData instance. This way you 
can copy your buffer into vtk's pipeline. There are ways in which you can 
share buffer created by you with vtk's pipeline but these are somewhat 
involved. Another possibility is, you create vtkImageData, configure it as 
above, get pointer to the internal buffer and use that buffer to load your 
data. I usually choose to let vtkImageData create and manage its internal 
buffers, get pointer to it and programmatically fill the buffer with some 
values.
HTH
Vidyadhar
----- Original Message ----- 
From: "Wesley Smith" <wesley.hoke at gmail.com>
To: <vtkusers at vtk.org>
Sent: Thursday, January 24, 2008 7:47 AM
Subject: [vtkusers] Volume data from application memory


> Hi,
> I'm just starting out using VTK and have been trying to figure out how
> to pass in volume data held in application memory (but not in any VTK
> class) into the VTK rendering system.  From what I've seen, all of the
> examples use "Readers" which only look for data from file.  Is there
> no such class that I can pass say a pointer along with the memory
> layout to?  To make things more concrete, I'm using a library to load
> VASP files.  From these, I get a buffer of data about 85x54x44 of
> scalar values.  What's the best methodology for getting this data into
> VTK?  Perusing the web, I've only seen examples that require
> subclassing a vtkReader of some sort.  Is this the only way?
> (http://www.comp.leeds.ac.uk/drm/ExampleVolRender.cxx)
>
> thanks,
> wes
>
>