Ray Gardener wrote:
> 2. When reading 16-bit grayscale TIFFs, shouldn't the Image->Image_Type
> field be set to IS16GRAYIMAGE? GeoTIFF elev data can't be used as
> heightfields correctly without this.

Well, when TIFF support was added, the assumption was that libtiff would
provide all the support needed. But as TIFF is a pretty messy file format,
and libtiff does a rather poor job hiding all that TIFF complexity, support
in POV-Ray is a minimal set of features. This means grayscale isn't
supported currently.

I haven't checked 3.7 source, but maybe Chris Cason fixed that bit when
porting the old reading code. You may want to check the beta and see if it
does work. If not, and assuming it is correct that we can fix it with a
one-liner in the current 3.6 code, I am sure it can be added in 3.7 - just
file a bug report for the 3.7 beta then (and refer to this thread, too).

Either way, I cannot recommend using TIFF images unless you absolutely have
to. I would recommend PNG images, which are much better supported in POV-Ray
 due to libpng being usable on a favorable level of abstraction that doesn't
force us to worry about format oddities too much :-)

	Thorsten

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