Sign in to follow this  
Guest lalo lolo1

32-bit textures? why?

Recommended Posts

Hi,Just thought I would ask this question.When I first started painting, I was under the impression that 32-bit textures gave a better "finish" in the sim.Now I know this is not the case, with a small amount of editing before compression, a DXT3 textures looks pretty much identical (at least as long as you don't get your magnifying glass out).Not only is the quality comparible, they are 4 times smaller in size, leading to less bandwidth for both host and client, and using less space on your HDD, and have a very benificial effect on performance in the sim.So my question is why do people still use 32-bit textures?Dan.

Share this post


Link to post
Share on other sites
Help AVSIM continue to serve you!
Please donate today!

I don't know Dan. The first thing I do is look at textures and change all 32 bit to DXT3. My old box just won't cut the 32 bit textures and my old tired eyes can't tell the difference. I guess mabey their for screen shots??Farmer

Share this post


Link to post
Share on other sites

Same thing to me. I really don't mind the small difference, because there IS a quality difference between 32bit and DXT3 textures, but unless you really don't zoom in a lot there's not much to tell, especially if you don't use the "Massive size" textures option in FS.Besides getting better frame rates DXT3 textures are also excellent for virtual cockpits because you won't be waiting 10 seconds to get them all loaded when you switch from the panel view to a side view.Most addons ship with 32bit textures like PSS, PMDG, FSD (but they have alternative DXT3 on their site), Flight1 and so on, sometimes it's a bit frustrating converting all the textures manually (Flight1 textomatic is very handy though) but I understand that some people prefer the 32bit textures on their high end machines, especially as been said for the eye candy or screenshots.There's just one point however. I wonder how many of those people complaining about textures loading times or frame rates know about the possibility of converting to DXT3, and so in my opinion all addons should be delivered with DXT3 textures because it's easy to understand that not everybody is a computer expert or simply because some people don't want to spend 1 hour converting textures.Much the same could be said about virtual cabins or animated passengers, though those are (fortunately) an option and can be disabled.

Share this post


Link to post
Share on other sites

"because there IS a quality difference between 32bit and DXT3 textures"Thats just the thing, if you just add a sharpen filter to the flattened BMP file BEFORE converting to a DXT3, the quality difference is extremely small.It is quite a pain to have to manually convert all the textures, plus the added bandwidth in having to DL files that can be up to 3 times bigger.I just think the quality differential is so small that is makes 32-bit uneeded.Dan.

Share this post


Link to post
Share on other sites

Well I can understand panel developers who start out with using 32-bit and then when all is complete as a last step convert to DXT3. But then in real life you can achieve higher quality by using DXT3 because it allows you to put in more detail when the performance hit goes down.Also there is ways to totally eliminate the detail loss by using DXT compression. ATI with their X800 have invented a lossless 3dc compression of normal maps which is used to give characters in fps games like Doom 3, Far Cry Serious SAM 2 etc a look that fools you that they are a lot more detailed than they really are. Now this technique should be perfectly possible to implement in FS 2006 as well. What they do is that they create objects with 100 000 polygons or something. Then create a normal map that consists of a fraction of that number of polygons. Then you compress that with 3dc which is similar to DXT5 but DXT5 causes some corruption so 3dc is better and ATI have support for it in their hardware. Could be used for autogen or airplane models to increase performance and/or image quality.I don

Share this post


Link to post
Share on other sites

Pretty slick lil Skyvan Dan. Good for first one, and no 32 bittextures. Whats next?Farmer old man in N. Texas

Share this post


Link to post
Share on other sites

What's next?, good question!!!I am currently making a small addon pack for the Skyvan, that will add the Skyliner PAX version, and also a VC.After that, its anyone's guess.........I did look at the IAI Arava, but information is scarce.Dan.

Share this post


Link to post
Share on other sites

<<<>>>Well, horses for courses I guess, Dan. I see a significant difference in 32-bit against DXT3 with certain finishes. Active Camera, particularly, gets us to places we've never been before! It's a trade-off; people with more modern machines have no issue with it, but those with older boxes - particularly if flying multiplayer, which I do with 15 or so others a few times a week - are sensible to reduce key textures to DXT3.When Jan Visser released the MAAM-SIM R4-D textures they were all 32-bit. He has since decided to release all 'painted' aircraft as DXT3, but keep the bare metal ladies as 32-bit. My latest repaints for the floatie are all 32-bit externals (and where there is fine detail inside) but with instructions included as to how to reduce textures if required. The size difference is substantial, as you say, and matters to many if they want a smooth sim.Mark "Dark Moment" Beaumonthttp://www.swiremariners.com/newlogo.jpg

Share this post


Link to post
Share on other sites

I have a fast box, but I still prefer the smoother, quicker loading DXT3 textures. I'm all about fluidity in the sim and I do think the pauses and jolts when heavy 32 bit textures load is annoying. Besides, I don't fly with a magnifying glass!Lee:-)

Share this post


Link to post
Share on other sites

How can I determine whether the textures associated with a particular a/c are 32 bit or dxt3.Thanks Barry

Share this post


Link to post
Share on other sites

Hi, Default aircraft is in DXT3 format, 32 bits will reduce aircraft loading and performance on any system, any higher format will take more time to load, higher format, will doubletripple the amount of MB for each texture for a low % change in visual, that's are going in the video cards, plus it decrease the frame rate, stutters and some will have trouble on the ground rendering etc.Using imagetool.exe from Ms to see the texture format, you can change to DTX3 format easly.Consider this is only one BMP, if there is many others add the % of KB vs MB1024x1024 Dxt1=682KB Dxt3=1.33Mb 32 bit=5.33MB <----------- rediculous amount for a low % on visual increase 512x512 DXT1=170Kb DXT3=341kb 32 bit=1MB ThanksChris Willis[link:fsw.simflight.com/FSWMenuFsSim.html]Clouds And Addons For MsFs

Share this post


Link to post
Share on other sites

Yeah I have to agree. I always convert the 32 bit textures to DXT3 (or even occasionally DXT1 for some textures) and I'm hard-pressed to tell the difference even when I zoom in and look closely. It just seems to me that the cost in performance far outweighs the visual benefit of 32 bit textures.

Share this post


Link to post
Share on other sites

>Yeah I have to agree. I always convert the 32 bit textures>to DXT3 (or even occasionally DXT1 for some textures) and I'm>hard-pressed to tell the difference even when I zoom in and>look closely. It just seems to me that the cost in>performance far outweighs the visual benefit of 32 bit>textures. I also agree with this. Seems like a huge price to pay for something that is barely noticable.

Share this post


Link to post
Share on other sites

Hello, "I also agree with this. Seems like a huge price to pay for something that is barely noticable. I agree, NOT worthed for the performance decrease!BestEric

Share this post


Link to post
Share on other sites

If you have lots of gradients and effects such as highlights on the textures, going from 32bit to DXT will make them look worse. But this is mostly to those people like painters who can detect the difference. Certain colors just don't come out looking right in DXT either.I can see the difference between DXT and 32bit looking at the texture, but in the sim I can't tell the difference.

Share this post


Link to post
Share on other sites

Oh yeah, definitely you can see the difference when you view the two textures side by side. But like you say, its much harder to distinguish any difference within the sim itself and that is really all I'm interested in...

Share this post


Link to post
Share on other sites

For one, it's included in the MS FS2004 SDK for GMAX. It may be included with gMax, I can't remember and it might be in the scenery SDK too, but not sure.Cal

Share this post


Link to post
Share on other sites

I use them in specific circumstances where that extra detail is required to render detail in the skins. Specific examples include bare metal detail and in some very complex curved skins where warp etc is difficult to manage. However, when I release a skin set, a lot of times I'll mix DXT3 and 32 bit depending on where that extra detail is needed. I almost never release a complete 32 bit set. Thats overkill most of the time.Eric

Share this post


Link to post
Share on other sites

Shouldnt be hard. use the following bat file to convert 32 bit bitmps to DXT3 in one go. Imagetool supports batch file handling.imagetool -batch -DXT3 -nomip -alpha *.bmpren *.mip *.bmpThe above saved as a bat file will covert files to DXT3 with no mipmaps and an alpha channel.Eric

Share this post


Link to post
Share on other sites

only diffence that i noticed is that if you use a gradient similar to a microsoft FS sunset and then you make it DXT3 you get a simitraspaerent aircraft at sunset.With 32bit you dont get that problem...BTW this is only with the FSD Senaca I havent used this on other aircraft....

Share this post


Link to post
Share on other sites

Thanks for all the response guys, very interesting.The reason why I asked, is because lately I have seen a trend for "most" textures to be in 32-bit, and I am even seeing lightmaps that are 32-bit.In my FS folder, I can reduce the physical size of one of my iDFG A319 texture folders from 40mb, to 14mb, by changing the textures too DXT3, and "in sim" they look identical.If everybody were to limit where 32-bit was being used (i mean is it really nessecary to have 32-bit gear textures?, or 32-bit interior textures?) we would save on download time, bandwidth, HDD space, not to mention increased performance "in sim".I think DXT3 format has a "stigma" attached to it for being bad quality, but this just isnt the case.CheersDan.

Share this post


Link to post
Share on other sites

I think mixing 32-bit and DXTC textures is the best approach. With certain textures, the difference is noticable while most of the time it is not.However, the idea behind DXTC was never to improve performance - it's supposed to increase *quality* - because the texture is compressed to 1/6th its original size, bigger textures can be used with good performance. This was demonstrated with the Unreal Tournament game - it included one whole CD of compressed textures that made the uncompressed default ones look like a joke.FS of course has internal limits to the max texture resolution so the primary use of compression is to increase performance. I can't say I notice much of a difference performance-wise with a 128MB videocard but 32-bit textures do take a little longer to load up when switching views.

Share this post


Link to post
Share on other sites

I just downloaded Chris Willis' newest cloud textures. I had these installed before, because they (a) improve performance and (:( make the fog look better. Before I install the new textures, though, one question: which set should I use for better performance, DXT3 or 32-bit? (I'm assuming from what I just read that the answer is DXT3.)

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this