[vtkusers] Problem reading in large textures in GeoTIFF format

[Mathieu Malaterre]

Hi Elvis,

On Thu, Nov 6, 2008 at 2:01 PM, Elvis Dowson <elvis.dowson at mac.com> wrote:
> Hi,
>        I came across an old post with someone else with a similar problem.
> How can I activate the logic in VTK to break apart the texture into multiple
> smaller textures?
> Here is a reply from Ken Martin
>
> My guess is that this is due to a texture size limitation in your
> hardware. If VTK tries to draw too large of a texture map some
> hardware will simply fail to draw the texture map. The result is a
> white rectangle on the screen. Since 4.0 we have added logic in VTK to
> handle this an break apart the texture into multiple smaller texture
> maps that do fit within the graphics hardware's limitations.

that's a *very* old post. This should be handle nicely now, Francois
Bertel recently fixed the vtkOpenGLImageActor.cxx too a couple of
weeks back. AFAIK vtkTexture is doing the right thing. Is there a way
to download your tiff file somewhere ?

Basically this is an OpenGL restriction, if your texture is larger in
size that GL_MAX_TEXTURE_SIZE, then the algorithm will split the image
as describe in the post you found.

2cts
-- 
Mathieu