#blurry texture map
12 messages in this thread
I got me a problem.
I have a large bitmap. The bitmap is a part of a satellite scene composited
with rasterized vector lines emphasizing certain features.
The problem is that the filtering is blurring the map and fuzzing out the
features on the top four fifths of the screen. This is the same problem
mentioned in the reference manual on pages 7-183 and 9-50, but I can't get rid
of it. I tried using summed area filtering, but it takes 115 megs to render
(fifty more than I got), and it didn't look any better. Turning off the
filtering in the render dialog box makes all the white pixels shimmer really
badly when I throw it on the PAR.
Do I have to live with this, or is there something I missed?
What's the resolution of the bitmap?
– G
>>What's the resolution of the bitmap?<<
The bitmap is 2009×2255.
There's your problem. If you're rendering this to video (720×480 or so), and
the topo mesh is taking up the FULL screen, you're maxing out the filtering
algorithm. If you've got a shot which starts out far away and then zooms in
close (the worst case), your best bet is to use the TEXTURE-SHARPEN hidden
3DS.SET parameter with values between .8-1.2 to bias the filtering towards a
less-blurry effect. But if you're staying a relatively-fixed distance from the
mesh, without getting too close, you should re-sample the bitmap to twice the
size of the screen (max… even less would be ok). You're better off with a
map that's too LOW res, than too high.
Experiment with a smaller map. It should make quite a bit of difference.
– G
Unfortunately, I can not reduce the bitmap. it is a portion of a SPOT satellite
scene and to resample it would lose information, so that idea is out. I try
your other suggestion and see how it goes. the topo mesh isn't taking up the
entire screen, but about the bottom two-thirds.
Why can't you just use 3DS to shrink it down to something more manageable, like
1Kx1K? Since it's only taking up 2/3 of the screen, that would certainly be
enough detail for low-res NTSC video.
– G
I think we may be miscommunicating on this map a bit, or I am not understanding
what you suggest. If I shrink my texture map down by half, then when the camera
gets close to the terrain all I am going to see are huge pixels. I have also
composited vector data (rasterized into a bitmap) over the top, and the lines
already look very alaised. If I shrink it down and re-composite the vectors,
they will look even worse.
Given the distance I thought you'd be from the terrain, a 1Kx1K map didn't seem
to be low enough to chunk up. Perhaps you're getting closer than I thought.
Regardless, instead of seeing huge pixels, it would just get a bit too blurry.
There are dozens of different ways to approach this situation, and without me
seeing all of your data and sitting down with you to analyze exactly what
you're doing, I can't really suggest specifics. If you'd like me to give you
some phone numbers of 3DS consultants who've done this sort of thing in the
past, I'd be happy to do that via email.
– G
the TEXTURE-SHARPEN seems to be helping a bit from the tests I've done, but I
think the phone numbers would be handy as well, so please send them along.
The topo mesh consists of essentially three valleys, with the camera flying
down each valley at about 80 mph, and roughly 500-1000 feet off the ground. The
view is generally a long perspective with the mesh taking up 3/5 to 4/5 of the
screen most of the time.
See your email.
– G
If this is used as a texture map, don't forget that the Materials Editor
default to a texture blur setting of 10. You probably would want to set that
to 0 in this case.
Terry Gilbert
Forcade & Associates
I set it to zero, and the white pixels shimmer terribly when I load it onto the
par, so at this point, I am looking for a comprimise between shimmer and blur.