Hello All,

I am working on the osgDB_lwo plugin.  I am trying to get it to use
transparency maps.  In OSG, I know I can use the alpha channel of the color
map to provide a transparency map. In LightWave, there is a seperate
grey-scale image that is used as the transparency map.  In the current
implementation of the plug-in by Marco Jez, that block is ignored.

I have it to the point in the code where I know about both blocks (alreadt
read in with osgDB from a file).  I have two conditions:
1.  There is a color map.  In this case, I need to grab the transparency map
and place its grey value in the alpha channel of the existing color map.
2.  There is not a color map, but only a base color.  Here I create the
color map by placing the grey value of the transparency map in the alpha
channel and I set the RGB values to the base color.

I have a pretty good idea how to do this if the images were already 32 bit
BGRA or whatever.  I am not as secure working with the other image types,
like if there is not already an alpha channel, or if the thing is using
grey-scale or an indexed color.  Should I create a new image and fill it or
can I use the rescale function to change it?  I am not sure how to create an
image from scratch without reading it from a file.  I am not sure about how
to read and write values to and from the images (except for the 32 bit case,
I got that).  Any help would be appreciated.  Any reference materials I
could read?  Gatchas I should watch out for?

Thanks in advance for any help,
-- Rick
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