[vtkusers] Render Speed (I know.. asked by many already..!)

[Lisa Avila]

Hello Ted,


>So I have set RenWin->SetSize( 500, 500 );
>Is this what you mean? BUt I woiuld like the option of having a bigger 
>weindow and not having to subsample my data

OK - so you have a 500x500 render window. How big is the input image? And 
again - did you time this only for the first render or do all renders take 
this long? (and is your pipeline changing every time?)


>>Also - you are using a vtkWin32OpenGLRenderWindow - it is the concrete 
>>class created when you create a vtkRenderWindow (assuming you are on 
>>Windows and not using Mesa).
>
>Okay my mistake, I forgot to mention I am on a Linux...........

Then you are still using OpenGL (unless you specifically requested Mesa) - 
but the X version rather than the Win32 version.


>And I have previously  tried NIgels' suggestion of 
>ImmediateModeRenderingOn but this doesnt make much difference

I am not sure this has an effect on rendering texture mapped images. In any 
case, this solution is generally good only when you pipeline is changing 
often - not when you are rendering the same texture mapped image many times.

>So is there  a better pipeline i shoudl be using? or does it seem vtk is 
>just too slow and I shoud resort to OpenGL... ! =(

VTK uses OpenGL for rendering - it is just abstracted at a higher level 
which is probably hiding from you the thing that you are doing to make this 
slow.


Lisa