A Huge FPS Increase

[Naicou 0]

Hello! Any tips, When i press start search i get error where it says: could not read the file C/Program Files(x86)/Microsoft Games/Flight simulator 9/Addon scenery/texture/1.bmp. And when i press Ok it just keeps goind another texture so any help?

[alpha117 73]

For what's it's worth; I've 'mipped' and 'alpha'ed' all my scenery in FSX. All I can say is that it worked OK, but not sure I can see any benefits, yet!

[kiwiflyer45 123]

I stated earlier that I had not encountered any negative effects. That's no longer true. Word to the wise - DO back up your textures before making changes... The two sceneries that did not like any of their texures getting "alphatized" (sic.) were the FZ Portland scenery and Real Air Simulations EG58 West Malling. (comes with their Spitfire XIV).. In both cases, restoring the original files resolved the problem instantly

Ian

[Kaan KASIM 54]

What kind of negative effects?

 

Btw, aerosoft stuff is full of alpha and mipmap problems.

[psolk 3,037]

What kind of negative effects?

 

Btw, aerosoft stuff is full of alpha and mipmap problems.

So is FlyTampa and every ImagineSim texture that I HAD MANUALLY MODIFIED BY BATCH FILE... UK2000 has some as well. I am about 80% through scenery thanks to the macro recorder then it is on to AI...

 

Mental note, test every scenery before doing long hauls thanks to Ian's info ;) Thank goodness I made backups of everything :)

[GaryGB 10]

Hello:

 

Folks interested to find out whether a dxt3 file has a alpha channel present may wish to review this thread at FSDeveloper:

 

http://www.fsdevelop...ad.php?p=142190

 

 

 

Also, see this discussion in the FlyTampa Forum:

 

http://www.flytampa.org/forum/viewtopic.php?p=30964

 

 

FYI: a version of "AlphaSearcher" is linked for download in both threads (login NOT required to view / download :P )

 

 

Hope this helps !

 

GaryGB

[Kaan KASIM 54]

Anyone noticed any quality loss? Dxt is a lossy format and I actually don't like the idea of resaving.

[psolk 3,037]

Wow, this is no small undertaking...

I have had the tool Kaan recommended running for 9 hours now. Almost done with AI now and then on to user aircraft! This has also been a great exercise to find those troublesome AI that did not have MIP Mapping or Alpha applied! I am hoping that will cure that list bit of stuttering at some of my airports with A LOT of AI....

[MeneMene 1]

About not applying mipmaps to a lightmap texture- does this apply in the case of sceneries as well?

 

And, could someone please give a step-by-step process for making sure all of my AI textures are alpha'd, and the non-lightmapped ones are mipped? Looking at the number of them missing mips, it's going to take a long time. I have some imagetool batch files that will apply mips very efficiently, but in the process, this will strip off the alphas, meaning I have to use DXTbmp to go through each file individually and resave with an alpha. Having never used a macro before for DXTbmp, how do I go about it? Windows doesn't recognize the file extension.

 

thanks

[atco 161]

OK I need to step in here before people make a huge mess of their FS install.

 

I'm going to claim that I am the one who discovered this issue, although it happened quite by accident and I seek no attention nor praise for its discovery. I assuemed this was a fairly well known problem but apparently it isn't.

 

There are two totally separate issues at play here. DXT3 textures and mip-mapping textures. Allow me to expand on both.

 

DXT3:

Back in 2008 I had my system worked on by FS-GS. Some of the best FS money I have ever spent.

Without revelaing any of the secrets of the service, which would not be fair, I was given a batch tool to convert textures into DXT3.

Prior to running the bacth my FS9 was running perfectly smooth as silk with all options maxed. FS-GS really had delivered.

I ran the batch tool on my AI aircraft to convert all the textures to DXT3 with mips.

 

After running the tool I fired up FS9 and got a horrible slideshow with frames in single digits. I was absolutely stunned, so I set about to troubleshoot.

 

I restored my original AI traffic textures and everything was fine again. I next tried to run the batch tool on just Alaska Airlines AI. I loaded up Seattle and got the horrible stuttering mess. I went over to Heathrow and all was smooth. I knew that I had to compare what the issue was by checking the textures from Alaska Airlines and British Airways.

 

Using ACES Imagetool from the FS SDK, I saw the following on the information pane on the right:

The BA textures were:

DXT3

Alpha: Alpha

 

The Alaska textures were:

DXT3

Alpha: None

 

To cut a long story short after some more testing and verifying I came to the conclusion that the batch tool had stripped out the Alpha from my AI textures. The problem was completely repeatable, DXT3 textures with Alpha were fine, DXT3 texures without Alpha caused horrible stuttering.

 

So the background..........I subsequantly learned that DXT1 textures are fine without an Alpha channel. DXT3 and DXT5 must have an alpha channel or there will be performance issues.

I have been told that the problem is caused by the graphics card trying to process the alpha on its own causing it major stress even at todays super high speeds. I would not claim to be an authority on that subject at all so I cannot say how factual that is, although given what these textures do in the sim it seems plausible.

 

Also while Imagetool reports that the "Alpha: None" its not technically correct. The problem is the Alpha flag setting within the texture is turned off, and Imagetool reports it as not being there. This is what Alpha Searcher looks for in each texture, whether the alpha flag is on or off.

 

I would very very strongly urge not using batch tools to do any of this. You are liable to end up in more problems than before you started. Alpha Searcher is far and away the best tool for dealing with this, and then I'm afraid its best to deal with each texture one by one.

*Disclaimer* Have not looked at or used any of the tools mentioned in this thread except for Alpha Searcher, so they may or may not work, I personally would not use one.

For example there are times when a 32-bit texture with an alpha when converted to DXT3 will lose the alpha. This happens when the Alpha is all white. There is a bug in imagetool where an all white alpha will cause the flag to be set off. DXTBMP does not suffer with this problem.

Any batch tool that uses Imagetool to convert to DXT3 is VERY likely to leave you with Alpha less DXT3 textures.

Another example would be any DXT1 texture without an alpha (which is perfectly acceptable) converted to DXT3 would also be missing its alpha.

 

So what happens when you find these problem DXT3 textures?

 

Well the solution fortunately is simple.

 

1) You can convert the texture to DXT1.

DXT1 is quite happy without having an Alpha. The Alpha is for transparency, if transparency is not needed there is no reason to use anything other than DXT1. When people wonder how certain detailed payware sceneries perform so well they are probably using DXT1 textures (think Aerosoft Munich, FlyTampa Athens etc etc).

 

2) You can resave the texture in DXTBMP.

You must use DXTBMP not Imagetool for this. DXTBMP will reset the Alpha flag and you can resave it as DXT3. You need do nothing more than save and overwrite.

 

 

Now in terms of performance.

This issue does not generally cause FPS loss as such, what it causes are stutters and usually quite large ones. Of course if you have a lot of these textures there will be so much stuttering the sim will judder to a slideshow. When you are removing 5-10 of these you will not see an FPS increase from 30 to 40, what you will see is a reduction in stuttering caused by these textures (Your system may have stuttesr caused by something else of course !)

 

 

Mipmapping:

This is a topic that causes a lot of opinions. I mipmap everything, but for mips to be effective you MUST have your graphics card and settings set up correctly.

Mips got a bad name years ago for causing blurry textures.

However with todays hardware and properly set up profiles in Nvidia Inspector mips are very effective.

Mips virtually eliminate shimmering and combined with a powerful graphics card which can use some transparency supersampling you can pretty much get rid of shimmering entirely.

 

It does not matter if you mip lightmaps, it was suggested to me not to mip night textures purely because at night there is a certain amount of shimmering in reality. Its entirely personal preferance on what you want to do. Personally I do mip night textures.

 

The only textures you should not mip map are VC textures, because you should never be far enough away from them for it to be an issue. Although if you have a really shimmering VC it may be worth a try (As with everything BACKUP first !)

 

OK, so I'll wrap this with the following.

I'm no guru, I'm not out to change anyones opinion or tell you what you should and should not do with your sim.

I'm merely presenting some information that worked for me and has worked for many others too, maybe something in here helps you too. One thing I am 110% certain of though is that DXT3 textures missing the Alpha channel will cause stuttering.

 

You will be amazed at some of the worst offenders in this regard, including everyone from FSDreamteam, Aerosoft, UK2000, some old FlyTampa scenery,Thai Creation, LatinVFR and on and on and plenty of flyable aircraft and AI textures. When I first rid my system I believe it took me around a week and I probably removed close to 1000 textures (and this was before Alpha Searcher existed ! - It was quite a job but well worth it in the end).

Now whenever I install anything into my sim I always, always check the textures first, whether its an AI repaint or a new scenery.

Again I would be very careful about using batch tools, they may cause you more problems than they solve - It is after all how I even became aware of this problem in the first place. I know that its time intensive to do it manually, but if your batch tool goes wrong it could cause you far more hurt.

I cannot recommend Alpha Searcher highly enough. I would use that to identify the problem textures and then either use DXTBMP to resave each texture one at a time or use Imagetool to convert the problem textures to DXT1 - This is faster because Imagetool can open more than one texture at a time and you can use a batchtool to convert to DXT1 without worry because DXT1 works with or without an Alpha.

One final note if a texture says Alpha: Colorkey that is fine, its is simply a black and white alpha. It is still an alpha however.

 

Hope there is something useful here, like I said I'm not proclaiming anything, this is something you may or may not find useful. I wish you all well with your endeavours and I'll pop in every now and again if there are questions. We had a very lengthy discussion about it all over at AIG years ago - For those that are registered there you can find the background and discussion in the forum section "AI resources and Tools" - For those that complain about having to register, you can thank the spammers and spam bots. Without a registration mechanism the forums would be over-run with spam postings - we have already been down that road.

 

Regards

Garry

[psolk 3,037]

Brilliant post, thanks Garry!

[atco 161]

Just seen a few things in the thread that need to be clarified.

 

1: 32bit textures.

So many people are fans of them. However, a vanilla install of FS will find zero 32bit textures. FS9 can display them that does not mean it was designed to.

Personally I do not have any 32bit textures in my sim. They are performance hogs and DXT3 serves me just fine.

Now many people swear by 32bit and complain about compression with DXT. Compression is a valid point, there is some quality loss with any of the DXT formats, but for me the performance gains are worth it. A 1024 texture sheet in FS at DXT3 with mips is 1.3MB, at 32bit that rises to over 5MB. Doesn't sound a lot until you think about how many AI textures are on display at a large airport, add on scenery, clouds etc etc. It mounts up, and just because the graphics card can handle them does not mean the FS engine can.

The fact that ACES did not include a single 32bit texture in a clean FS tells me something.

For me the performance/quality tradeoff is worth it. I do not find DXT3 to be an issue. Even with flyable aircraft, I always convert the 32bit textures. With mips too.

 

2: DXT

DXT3 and DXT5 textures have to have an alpha. If they don't you will get problems. Doesn't matter if its a _T.bmp an _L.bmp or any other sort of bmp. If you have a cloud, or AI or ground tile that is DXT3 and does not have an alpha then it will cause a stutter.

The alpha is related to transparency/reflectivity, thats what it controls. Any texture that does not have a transparency can be DXT1 without alpha or DXT3 or DXT5 but must have an alpha.

Any texture that needs trasparency/reflectivity will have to be either DXT1 or 3 or 5 with an alpha.

 

So to answer Paul's question:

AI:

DXT1 or DXT3 is acceptable for both day and night maps

DXT1 can be with or without alpha

DXT3 must have an alpha

Mips are personal preference, they are recommended, infact ACES mips the default textures in FS.

Without mips shimmering is possible.

Personally I mip all the textures:

 

Scenery:

DXT1 or DX3 or 32bit

As I spoke above about 32bit, thats user preference. I avoid them at all costs.

Same rules with DXT1 and DXT3 regarding Alpha, no idea if 32bit textures need an alpha because I don't use them.

Same regarding mips, infact almost all scenery developers these days mip the textures anyway (FlyTampa for example)

 

DXT3 Clouds:

DXT3 HAS to have an Alpha channel regardless of what its used for. DXT3 coulds like anything else will cause stuttering if they do not have an alpha

 

User Aircraft:

DXT1, DXT3 or 32bit

Again, I never use 32bit textures, I always convert to DXT3 with mips.

Mipping helps with shimmering as always.

 

VC:

DXT1, DXT3 or 32bit

Should not be mipped unless shimmering is unbearable although generally it will not be an issue. I have mipped VC textures before without any problem. As always you can always back up and try and revert to the backup if you don't like the results.

Again I never use 32bit textures personally.

[mebull 27]

Thanks Gary and everyone else that is contributing to this post. I started running AlpaSearcher last night. I chose to start with my scenery object libraries. There were a least forty files that needed fixed. Folks this is going to take a while!

 

To Gary: As I was going through the texture folders I noticed a large number of 256 color image files. They were not typically flagged by AlphaSearcher so does that imply that they are alright as is or should they be converted to dxt1? And, in doing so will that conversion cause any color or detail loss? Note; I realize that MS has used 256 color and therefore probably okay, but, I thought I would inquire just for the sake of covering all the bases. Thanks.

 

Best regards,

Mel

[psolk 3,037]

Mel,

use the macro recorder Kaan suggested earlier. You just hit start record, go through the normal process for one file then stop recording and tell it to repeat. Just took me ~ 12 hours to do all of the applicable files but doing it by hand would have been days!

[CaptKornDog 281]

I think I'll hold off and wait to hear some more results before diving in.