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Rumr
02-12-2007, 05:45 PM
Im trying to render a business card and get a clear and crisp look from the text, so I set this up with mitchell filter type but i get ugly edges, what do i do to get crisp text texture and nice edges on the grid as well. Can someone help me out here.

Thanks
James

http://www.rumr.com/ss/ssbc.jpg

mocaw
02-12-2007, 06:03 PM
Well...I'd say you need to up your AA levels- try 0 and 2 at a bias of .15 and see what happens- you might need to go 1 and 2 or more on the samples. Maybe I'm wrong too...but Mitchell gives you sharper edges right? You might try a few of the other filters like triangle.

Also try rendering it out at a higher resolution, then scale it down in PS.

Those are my helpful "guesses"

Rumr
02-12-2007, 06:16 PM
I can get clean edges no problem its just the text on the map will look blured and not sharp at all

Rens
02-12-2007, 08:11 PM
Two things to try:

- Open the Render Tree of your business card object. Then open the image node's properties and go to the Image Filtering tab. Enable in RGBA. This increases render times but also increases the texture quality.

- In the image you posted the Filter Size is set to 1, try increasing it to 4.

Good luck!

mocaw
02-13-2007, 02:02 AM
Thanks for the info Rens!

ThE_JacO
02-13-2007, 03:35 AM
I mean absolutely no offense with this, but...
if you think a mitchell filter with a size of 1 would make any difference from a box, then you need to look into rendering fundamentals real bad.

you should still be able to find a paper on soft's site by Dave LJ that provides some middle level information, and you should try and find the old production DVDs, the rendering one is actually fairly technical, yet approachable.

I know some people don't want to be a rendering TD, but completely overlooking the basic notions of it is a big mistake that can cost you anything between hrs and a lawsuit on a job.

mocaw
02-13-2007, 06:49 AM
This site as always seems to have helpful info:

http://www.lamrug.org/resources/samplestips.html

When I first answered I was going off of the fact that the general AA of the image was kind of aliased in general. I did state they were guesses though! I often don't touch the filter sizes for most of my work like this since it is often print resolution, but I guess I should be looking into it more...

ThE_JacO
02-13-2007, 12:21 PM
I would say that knowing what the antialiasing values are and do is about as fundamental as it is knowing how to push points around.
It really isn't that hard to understand the problems and the concepts and how they relate.

That's why I was advicing about the softimage dvds and paper, they offer and explain just those few things you -really- need to grasp to get yourself out of trouble most of the time.

Once you understand those you should be able to not guess settings so randomly anymore and have a better knowledge of what will affect times how much, which considering the importance of compromising in rendering is probably an important bit of knowledge to have :)

Rumr
02-13-2007, 06:34 PM
I know antialiasing, but if I make the cards edges look nice the texture doesnt look crispy. So I get one or the other Im trying to get my texture to be crips and vector looking not blury.

RKanyama
02-13-2007, 06:51 PM
If you are not animating the scene, just go to Photoshop and use the blur brush on the edges.

My 2-cents...

mocaw
02-13-2007, 08:25 PM
Did you look over that link I posted and look up filter settings? It basicly answers some of your questions- and mine. I think Mitchell is supossed to be something like 4-5 samples and only box is to go as low as 1 on average. If I'm not mistaken part of your problem is your sample settings for your filter choice- but the filter, under my understanding, would be one of the last things you'd adjust.

Someone please correct me if I'm wrong, but wouldn't you first set your adaptive AA settings, then adjust the adaptive bias, then select your filter settings?

You might want to go into diagnostic mode to try and figure out what is going on and how it's being sampled. I suggested triangle because it renders quickly and I personally like how it often looks on edges- at least with "toon" renders and other crisp objects.

And I still stand behind the fact, maybe incorrectly, that you need to increase your render size an to get more pixel information going and to help prevent over sampling blur. Would you be willing to upload such a simple scene for some of us to look over? I too am learning so I'd like to have a crack at your problem.

Rens-
So does Image Filtering-> Enable in RGBA make it so that the samples evaluate more than just gray scale contrast and instead the difference between all channels or something?

Rumr
02-14-2007, 03:34 AM
The top render has a cripsy map but the poly has ugle edges, here is the normal render and the texture map looks kinda blury but thats the best i can do take a look.
http://www.rumr.com/ss/bc1.jpg

Mic_Ma
02-14-2007, 04:50 AM
Well, as I understand it you want non-jagged polys and sharp textures. and can get either but not both in one render.

Why don't you just do 2 passes with different settings for each?

Sbowling
02-14-2007, 05:06 AM
The top render has a cripsy map but the poly has ugle edges, here is the normal render and the texture map looks kinda blury but thats the best i can do take a look.


If that is the size you are going for, you aren't going to get good looking text, because the pixel size is too small. When the size of the fonts is only 3 or 4 pixels high, it is going to always look bad. There just isn't enough pixel resolution to get clean sharp text.

Another problem is that you are doing black on white, which can also cause AA problems because of the large difference in contrast.

mocaw
02-14-2007, 05:28 AM
With all due respects I think that is NOT true. YES there maybe some give and take here- but not on the level he's getting. After doing some test a VERY obvious question came to mind- are his textures at a high enough resolution so that they aren't being sampled to a blurry mess?

Here is a quick test using a quick vector image that has been turned into a raster one at 300dpi 5"x5" - I didn't render it above screen resolution and reduce it- and yet I think I'm getting clearer lines than you. Triangle gave me better edges, but Mitchell gave me slightly better textures. Some blur was introduced by the jpeg compression. I wish I could upload the Tiff.

I'm lead to believe that if you rendered it at a slightly higher resolution, and used a higher resolution texture your images would be in much better condition. Yes, the filter will make a difference- but it shouldn't be so harsh.

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02-14-2007, 05:28 AM
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