#Alpha question
4 messages in this thread
Gary,
I have a question that I don't have clarity on, perhaps you can help.
I get an error message when I render an image that says, " Warning: Texture map
x.tga is used in two places with conflicting use of alpha
.." How can I change the imaginary existence of the alpha map and not the
texture? There is no alpha information in the texture map, but I want to use
the texture map. How does this work and how can I avoid this common problem?
And while I have your attention, I've got another question regarding alpha.
When I render an image with the alpha channel on, I look at the rendered image
using PhotoShop or QFX and find no alpha channel. Looking at the raw file in
hex it seems as though the alpha channel is on but it is just filled up with
blank information, and no alpha from the image. Because alpha is essential with
my video-oriented animations, I either have to use TOPAS to re-render the
images or create the alpha in QFX (providing I save the animated sequence of
images uncompressed) in a batch file. What gives?
That's it for now. Thanks in advance.
-Gregory MacNicol
P.S. The 3DS newsletter is getting resurrected. Tony dropped out and I'm going
ahead with it anyway.
Gregory,
<where's my alpha data? >>
some questions, Is render options-render alpha On?
-Alpha Split-No?
render still image-configure-Targa?
jonas[adesk]
Gregory,
In Photoshop, assuming you rendered a TGA with alpha on and alpha-split
off, then just go to the selection menu and hit 'load selection'. This will
load the alpha channel as a mask.
And about the "…conflicting use of alpha…" in the maps message, I
got that too when I rendered a scene in r3 that was done in r2. I just ignored
the message and rendered anyway, and it rendered fine, even as a 32 bit file. I
am curious to know what it means though.
David
David's comment re how to access the alpha channel that 3DS creates in
Photoshop is right-on.
Regarding the "conflicting use of alpha" message… that will always appear
when you're using the same 32-bit file in two different materials, when one
material is set to Decal/Both and the other material using that map is set to
Tile. The renderer has to decide which optimal way to use the alpha channel,
and since decal and tile each have different optimal requires for
pre-multiplied alpha, it can only do it one way. Most of the time you'll still
get a decent (albeit not perfect) result, but if you want to avoid it
completely, you can copy the .tga to another filename to create a second
version of it and use both of them… each with their own setting.
Good luck with the newsletter!
– G