MCX Using LOD to Change Objects - Runway Lights

[Smart]

I know there is Airfield Light Toolbox out there for the purpose, but I'd like to try this one to see how it works.

I created 3 different sizes of runway light sets, so the runway can be seen during the final approach (large white light), and the light details (small white light with bulb) can be seen while I'm on the ground.

The 3 complete sets of runway lights were placed on 3 different files, all of the same coordinates and center (0,0), then converted from SketchUp file to Collada (.dae).

Here's how the size of the lights are different in each set

In MCX (v1.5), I loaded the 1st set (detailed runway light), set coordinates and a heading to my airport references. Then I open the LOD window to add LOD.

At this point, I'm not sure what is the value I should put to each LOD, in order to get the them displayed at appropriate distances (the large light set should be displayed miles away, the middle light set should be displayed during the final approach, and the detailed light set should be displayed when on ground).

Are there any rules of thumbs to assign certain numbers to the LOD? Does it depend on the size of the individual object in the group or the size of the group of objects?

I tried to put a set of green / yellow / red cubes (each cube is 20x20x20 meters, put them in a row with 100 meters spacing to get the total length of 2000 meters, pretend as they are runway lights) and assigned different LOD numbers, but the results were still not the way I like.

Green cubes are LOD 800
Yellow cubes are LOD 600
Red cubes are LOD 400

The cubes change from green to yellow at 3NM, then changed from yellow to red at 4.8 NM.

I think there should be better solutions to solve this than trying assigning different LOD numbers randomly.

 

[tgibson]

I have been told that they change based on how many pixels they cover on your screen. Since this is highly variable (and also involves the size of the objects themselves) I can't imagine a way to do this other than trial and error. What I did was change the color of the light for each LOD so I could watch them change color as I approached the airport, much like your cubes.

 

[Smart]

Thank you.

 

[rhumbaflappy]

Zooming in the viewport will also change the LOD. It's not a good way to control visibility by distance. The LOD is controlled by the percentage of vertical size of the viewport.

 

[Smart]

Zooming in the viewport will also change the LOD. It's not a good way to control visibility by distance. The LOD is controlled by the percentage of vertical size of the viewport.

I already tried that and found the result exactly the way you explained. So, there's no way to make it work the way we want?

 

[tgibson]

That depends on how you want it. I don't see a problem with changing LODs when zooming - that seems logical to me.

 

[Smart]

That depends on how you want it. I don't see a problem with changing LODs when zooming - that seems logical to me.

At night, during the final leg when we try to line up with the runway, we normally try to aim at the runway light, and PAPI (in case of a small airport without more advanced runway lights). It's important to make sure we put the appropriate LODs so the lights can be properly seen as we are getting closer, without zooming.

 

[rhumbaflappy]

I think there may be a way using code similar to the Marshaller SimObject animation. It uses distance from the Marshaller to the Aircraft.

 

[Finni]

This was posted under msfs, but I believe the Sim you're using is p3d?

Why not just use the lights included with runways in the Sim?

I've done several airports with custom runway lights, and I'd suggest looking into manually editing mipmaps. With imagetool you can use the texture/mipmap to achieve the lod switching you are talking about.

- Finn

Sent fra min MAR-LX1A via Tapatalk

 

[Smart]

This was posted under msfs, but I believe the Sim you're using is p3d?

Why not just use the lights included with runways in the Sim?

I've done several airports with custom runway lights, and I'd suggest looking into manually editing mipmaps. With imagetool you can use the texture/mipmap to achieve the lod switching you are talking about.

- Finn

Sent fra min MAR-LX1A via Tapatalk

Ah! Sorry I started in the wrong section. Yes, it's P3D.

The point is that I want to create the light that can be seen, not the bright dots that will disappear when we get close to each one of them.

I consulted with another airport builder, and he also suggested editing MipMaps, but I still don't have a clue how to achive that.

So you meant we need the appropriated LODs numbers with appropriate MipMaps?

 

[Smart]

I think I got it now, figured out how to modify MipMap to get the appropriate result, together with setting appropriate LODs numbers.

Effects cause fps drop?

I think I got a sweet spot. Only one emitter and bigger spot, increase X, Y, Z to 2 meters. Make texture brighter to simulate the bright light in the middle. Visibility range is good, the light is good and frame rate is acceptable. Only one problem is the offset. I need another tool from...

www.fsdeveloper.com

Case closed.

 

[CasRi]

I think I got it now, figured out how to modify MipMap to get the appropriate result, together with setting appropriate LODs numbers.

Effects cause fps drop?

I think I got a sweet spot. Only one emitter and bigger spot, increase X, Y, Z to 2 meters. Make texture brighter to simulate the bright light in the middle. Visibility range is good, the light is good and frame rate is acceptable. Only one problem is the offset. I need another tool from...

www.fsdeveloper.com

Case closed.

May I ask how you did this exactly?

 

[Smart]

May I ask how you did this exactly?

You need to edit your light texture file using "ImageTool", which can be found in all versions of P3D SDK packages.

Once you open your light texture file (.DDS), it will show mipmap images (a total of 8). My light texture file is 512x512 pixels. The next image will be 256x256, 128x128x, 64x64 unti it becomes 4x4.

You need to use any graphic editor to edit the runway light (and the green light in my case) and safe them in DXT5 format before you add it (or them) (using command "Add mipmap" back to the original light texture file (.DSS) , to make sure it's big enough to be seen when P3D will pick the smaller images when you're far away from the obect (i.e. the runway). You can see that image 6-7-8 is a white stripe, not light dot, to make sure they can be seen.

If you change itmage 4, the smaller images will be changed following the size (devided by half), so you may need to create image 5-6-7-8 for your complete mipmap texture.

Again, you will still need to set appropriate LOD numbers in MCX for each LOD, so the texures can be called at the appropriate distance. This is totally trial and error method, you have to assign nubmers for each LOD and test the flights (Slew away, or back and forth, from or to the runway at night).

Hope this helps.

 

[CasRi]

You need to edit your light texture file using "ImageTool", which can be found in all versions of P3D SDK packages.

View attachment 79104

Once you open your light texture file (.DDS), it will show mipmap images (a total of 8). My light texture file is 512x512 pixels. The next image will be 256x256, 128x128x, 64x64 unti it becomes 4x4.

You need to use any graphic editor to edit the runway light (and the green light in my case) and safe them in DXT5 format before you add it (or them) (using command "Add mipmap" back to the original light texture file (.DSS) , to make sure it's big enough to be seen when P3D will pick the smaller images when you're far away from the obect (i.e. the runway). You can see that image 6-7-8 is a white stripe, not light dot, to make sure they can be seen.

If you change itmage 4, the smaller images will be changed following the size (devided by half), so you may need to create image 5-6-7-8 for your complete mipmap texture.

Again, you will still need to set appropriate LOD numbers in MCX for each LOD, so the texures can be called at the appropriate distance. This is totally trial and error method, you have to assign nubmers for each LOD and test the flights (Slew away, or back and forth, from or to the runway at night).

Hope this helps.

This has been some great information already,

I do have some follow up questions though. When we add an LOD we have to import another model again, this would then be the same one as we had before. Do we need to create a bigger model? How do we tell it to take another mipmap? Also what is the LOD logic exactly, 1 = closer and 100 = farther?

Could you maybe tell us some baseline numbers. I'll be forever grateful!

Kind regards

 

[tgibson]

Mipmap loading and LOD loading are really two separate things. Mipmaps work even with a single object, they will change as distance increases. The LODs are to keep frame rates up. They usually do not change at the same time mipmaps do.

 

[CasRi]

Mipmap loading and LOD loading are really two separate things. Mipmaps work even with a single object, they will change as distance increases. The LODs are to keep frame rates up. They usually do not change at the same time mipmaps do.

Do the mipmaps load automatically in MCX? And can you see the different looks it gets in MCX?

 

[Smart]

Do the mipmaps load automatically in MCX? And can you see the different looks it gets in MCX?

Yes, mipmaps will change as you move away from the object, the very same object. I haven't tried using a single LOD with adjusted mipmap yet. We might not need to even make more model, the way I did at the beginning of this thread.

Base line LOD that I use for the airport light (that covering 2100x45 m. of the runway) is 900. I made 5 models, and assigned LOD 900 / 850 / 800 / 500 / 200.

 

[CasRi]

Thanks a lot, we figured it out!