Christian Froeschlin wrote:

> Paul Bourke wrote:
> 
>> Any comments on why the following doesn't work
>>     http://local.wasp.uwa.edu.au/~pbourke/tmp/sim/testmodel.zip
> 
> According to the docs, the alpha channel is used for *non-filtered*
> transparency (i.e. transmit instead of filter)

I just looked into the sources and the corresponding code
lines are in image.cpp (ColourMapImage::GetRGBFTValue)

   transm = 1.0f - e.filter;
   filter = 0.0f;

So, if you really need it, it would probably be reasonably easy to
build your own executable which uses filter instead of transmit.

On the other hand, these lines are marked with:

   // TODO - should alpha be converted to filter and transm? [trf]
   // currently we just return (1.0-alpha) as transmit, this isn't
   // a good solution. [cjc]

I think a clean solution would be to allow to specify
something like "filter alpha" in an "image_map" to indicate
that the alpha channel shall be used for filtering.

Post a reply to this message