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A closer observation of the DX10 issue with IVAO MTL aircraft

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Have been trying to find a good solution for the problem where IVAO MTL aircraft are not displayed correctly during night and today I did some more testing and what I found out was that in fact all of the aircraft is displayed correctly except for the parts lit up by the logo light and the landing lights. Below is a screenshot showing this where I highlighted the problem areas and also an example of the other parts of the aircraft that are displayed just fine even during night.

 

This is with the DX10SF Legacy Shader slider one notch to the left and I need to leave it that way because otherwise I will run into problem at LGTS where the end of the runway all of a sudden has a very weird reflection. Just for the sake of testing I tried moving the Legacy Shader slider all the way to the right and then the issue with IVAO MTL aircraft is gone but this isn't a solution since that will brake other things such as the issue at LGTS.

 

So...now I'm wondering if there is anything I could do to fix this issue with IVAO MTL aircraft models. I know nothing about painting a/c etc but to me it seems like the problem is more related to the lights that illuminate the aircraft rather than the a/c texture itself...?

 

The IVAO MTL database of AI aircraft is really a great one so it would be super if there was some kind of solution to this. If not I guess I'll give UT2 a go because I heard the AI aircraft in that product should be DX10 compatible so hopefully they will display correctly without having to move the Legacy Slider to the right. Have asked for a confirmation of this over in the UT2 forum but haven't received any answer yet.

 

Oh well...here's the screenshot showing the issue and as you can see it's only the parts of the aircraft illuminated by the logo light and the landing lights that have this problem where the logo on the fuselage for example is displayed just fine even during night.

 

DX10%20problem%20with%20IVAO_MTL%20aircr

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I do not use the MTL, but I can tell you from looking at your shot that this isn't likely a DX9 vs DX10 issue, but more of an FS9 vs FSX issue.

 

You can achieve exactly the same effect when using any model and repaint that was designed for FS9, in FSX, because they way lightmaps are handled was changed quite significantly. It is possible to change the night texture only to achieve an acceptable effect while using an FS9 model, but for older models this must be done for each and every livery, and is not without tradeoffs when dealing with older models.

 

UT2 has indeed re-compiled some, but not all, of the popular AI models for FSX compatibility. It is certainly a good starting point, and if you aren't an AI nut, a good solution overall. Since I am a bit of an AI nut, I personally went ahead and bit the bullet last year and recomplied all of the models I use for FSX via the SDK, and then created proper FSX lightmaps for each paint.

 

It is quite a job as you can imagine, and I still have a lot to do.

 

EDIT: Here is a screenshot to better illustrate the differences:

 

y1ja.jpg

Edited by Brian Doney

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To add a note, Richard - the early DX10 Fixer manuals contained a method for fixing this issue, but the newer manuals do not. You might raise this with Steve when he gets back next week.

 

pj

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Many thanks for your very interesting reply and explanation Brian!

 

So maybe I've had this issue with the IVAO_MTL models even when using DX9 only that I didn't notice it until now. 99% of my flying is during daytime so that could explain why it took me so long to see the problem.

 

However regardless if it's a DX9-10 issue or a FS9-FSX issue it would be nice to have an AI package with models that look good both during the day and night.

 

I downloaded the UT2 demo just to check out the models and so far they look good but I have a weird issue with the lighting of the AI models where the logo and cabin lights are OFF. Doing a Google search I found someone else asking about the same thing and the answer was you need to manually switch the logo and cabin lights ON by pressing 'L'. I found this a bit weird that you need to manually do this for AI aircraft and also I couldn't get it to work because when I pressed 'L' the logo and cabin lights would only come ON for a split second and then when out again.

 

When I did this I was in the PMDG NGX so I thought maybe I should try pressing the 'L' key when I was in a default FSX aircraft instead. That fixed the problem and after pressing 'L' all AI aircraft suddenly had both logo lights and cabin lights. Then I changed back to the NGX and all lights were OFF again...hmm...

 

Do you really need to keep pressing 'L' whenever you do a flight at night to have the AI aircraft logo and cabin light work?

 

And one more question about the UT2 models, is it correct the landing lights don't illuminate the fuselage? At least they didn't in my case.

 

Looked at your screenshot but I'm sorry to say I have no idea what I was supposed to look for :wink:

 

Do you know if there's a tutorial somewhere describing what you've been doing to fix the lights in FSX? Probably I wouldn't have the time nor the patience to go through all models but would be cool to try it on maybe a few models just to see how it works.


To add a note, Richard - the early DX10 Fixer manuals contained a method for fixing this issue, but the newer manuals do not. You might raise this with Steve when he gets back next week.

 

pj

 

Thanks Paul, I'll try to remember that unless Steve finds this thread himself and replies to it when he's back.

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Well, the screenshot is just a night texture example, for a Delta 77L, FSX vs FS9 side by side.

 

In FS9, by default the sim itself would "multiply" the night texture over the day texture. This is why, if you look at the FS9 side, the night texture is more of a simulation of how the light would fall, and does not include any actual details of the paint. FS9 handled the blending on it's own.

 

In FSX this changed, where now the default behavior was to ADD the night texture over the top of the day texture, and for this, no longer was it ok just to simulate the light, now the night texture must be an exact representation of how the lit up areas of the aircraft would look at night, all paint details included.

 

Just look at the tails on each side, that should help clear it up. (note the FSX side is flipped as it is a DDS vs BMP for the FS9 side)

 

Eventually MS did revive a similar feature, I think with SP2 (maybe even SP1, I don't recall), called multiply blend. It wasn't until after a good deal of the work had been done on UT2 though as far as I recall, and none of the UT2 models use this method. It is also not a direct replacement for the multiply method in FS9, and results in much dimmer night lighting, that really isn't visible until the sim is much darker, compared to FS9.

 

The UT2 models use a method called "Additive Night Only User Controlled", which is why you see a need for your lights to be on for the AI to have lighting. There are a few methods that can work better than this method, but again, I do not believe any of them were available when UT2 was in work. For the models I converted, I simply went with Additive Night Only, removing the User Controlled requirement, for automatic lights when the sim decides it is "dark".

 

Newer models, like the wonderful FAIB models, use a combination of Multiply Blend, and proper use of alpha channels in FSX, to achieve very good results, with the only negative being the dimmer lighting that I talked about above. It is likely the best solution, and allows for proper landing light splashes, etc. This is much easier to do with a model designed with these features in mind though, then it is to convert an FS9 model in the same fashion.

 

For more information on the conversion process, here is a good place to start:

 

http://www.fsdeveloper.com/forum/threads/fs9-fsx-aircraft-model-conversion-an-experiment.427512/

 

It isn't "technically difficult", but is a bit time consuming and requires a bit if trial and error. Should you decide to go further with it, feel free to message me and I'll try to answer any questions you might have.

Edited by Brian Doney

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Again many thanks Brian for your very thorough and informative answer!

 

I did some more testing with UT2 and the demo I downloaded and I'm not sure if it's just me doing something wrong but I can't get the logo and cabin lights to work the way they should when I'm in the NGX. Yesterday when I did the first test I later thought the problem was that you don't control the lighting in the NGX using the default FSX shortcut 'L' but today I tried manually switching the logo light ON in the NGX and still the logo light on the UT2 traffic remained OFF.

 

So...I now decided I'll stick with the IVAO_MTL package since I find that very good overall except for the issue discussed previously. However maybe I'll try to see if I can fix some of the models using the method you've described and I will definitely have a look at the link you provided! Probably I'll also have a look around that fsdeveloper site, very interesting reading!!

 

All the best,

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Glad to help.

 

For the record I think it might actually be the FSX nav or panel lights command that control the AI lighting, though it has been awhile so I am not certain.

 

I realize it may be a lot more information, and definitely a lot more work, than you were hoping for, but this is the situation as it stands. There are some recent rumors that work has been done to update many of the models by, or with permission, of the original model authors. This is good news as it would allow for distribution/upload, something which I obviously cannot do. I am keeping my fingers crossed.

 

In any case, even though manual conversion is a bit of a job, the results are definitely worth the effort, in my opinion:

 

jaft.png

7q9x.png

vj4i.png

Edited by Brian Doney

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Those are really beautiful examples how good it can look when all is in order!

 

Thanks for the tip regarding how to switch UT2 AI lights ON/OFF but I think I'll settle with IVAO MTL models now, already deleted the UT2 demo.

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With dx10 it's pretty straightforward to explain.

 

The legacy model can specify three options

 

Night texture . There are two textures for day and night , during dusk and dawn they are blended together.

 

Light texture, there is a day texture and a texture of lights as in the posts above which is combined with the day texture when appropriate.

 

Light texture with alpha - the alpha distinguishes which portion of the light map are used when the landing lights are on

 

The information the shaders need to know how to handle night lighting are discarded by the fsx core. Therefore the only mechanism to make it work in dx10 is the slider.

 

When it is over to the left, it assumes everything is a night map, when to the right it assumes everything is a light map.

 

When its in the middle it uses the presence of specular lighting in the material to guess how to display - specular is much more common with aircraft which almost always use light maps,

 

If you have an airport that requires the slider to the left how far to the left? As Paul suggests the only option is to take the aircraft light texture and blend it with the day texture in Photoshop to arrive at a fairly good representation that will work with the slider to the left.

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Thanks Steve!

 

To answer your questions, the only airport where I've found I need to have the Legacy slider to the left is Aerosoft LGTS and only one notch is required. I posted a screenshot showing this issue somewhere in this forum.

 

As for the AI aircraft (the IVAO_MTL models) I don't have Photoshop but I remember downloading some other similar freeware program in the past that maybe would let me do some experimenting with what you suggest blending the textures.

 

Since there are thousands of models in the IVAO_MTL I think it would be a very hard and time-consuming work to fix all the models manually even if it's would be possible but I would be more than happy if I managed to fix at least the most common liveries such as KLM, British Airways, Scandinavian, Norwegian, Air France, Lufthansa etc.

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If you'd like I'd be happy to show you how to create FSX style night textures in Photoshop or if you prefer, Paint.net, which also does just fine.

 

Once you get the hang of it it literally only takes a minute to do, for textures anyway.

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If you'd like I'd be happy to show you how to create FSX style night textures in Photoshop or if you prefer, Paint.net, which also does just fine.

 

Once you get the hang of it it literally only takes a minute to do, for textures anyway.

As I don't have Photoshop if you could show me how to use Paint.net to make an IVAO MTL model fully DX10 compatible I would be most grateful.

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Just looking at the link I thought Paint.net was some online freeware alternative but now after I checked the link it seems to be a payware product?

 

I just checked out the freeware software I know I've used before and it's called Gimp found here -> http://www.gimp.org/

 

I wonder if this software could be used to convert IVAO MTL models to DX10 compatible models?

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Hi Richard:

 

Adobe released CS2 as freeware about a year ago (for technical reasons) and I just checked - it is still available here. You will need to create an account first, (email address) and then go to that same address once you've logged in. The passwords for each product are in a box alongside the d/l link.

 

All the Best,

 

pj

Edited by Paul J

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Thanks Paul!

 

Do you think this software (CS2) would be easier to use for converting IVAO MTL models to DX10 compared to Gimp (if it's even possible to use Gimp for this of course)?

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