P3D v2 P3D V2.2 issue or a Ground Poly Wizard issue?

[Fabigo]

Hi Arno,

Okay, now, i set again the P3D patch and run as administrator and compile with GPW P3D V2 output mode de-selecting "Ground Polygones" option and now compile the BGL file. (Good news for now).

But in Prepar3D i look that the wheels is below ground poly.
I compile on layer 1 and the wheels is light below GP
whe compile on layer 16 the wheels are very below of GP.

On boths layers the aircraft no project shadows on Ground Poly...

I put correct altitude on Wizard (73 meters for this airport)

what i thinks, it is to place a platform, but this meas that i will need go up all 3D building.

 

[Tisor]

Illustrating the problem, when the GP is fix so it receive shadow and everything is correct, now the problem comes on the elevation, with the wheels/skids getting a bit into the polygon. Just used GP Wizard with P3D v2 option, testing on v3:

I've tried in the mid and in the end of the runway, to see if it does varies with the curvature thingy, but looks the same... Getting crazy with that

 

[arno]

Hi,

The GPW places the polygons 1 or 2 centrimeter above the ground, to prevent flickering. So a tiny bit of sinking into the polygons is normal (I expected 1 cm would not be a problem).

It's interesting that a different layer (zbias) also seems to influence this. In a few that's logical, but that's done by the rendering engine and not something we can influence. The zbias gives the polygon more priority when sorting the z order and it might well be that internally that means it's raised a bit.

 

[Fabigo]

Hi,
But, it´s very confuse. But when i put for example layer 16, seems that GP is 20cm above ground. Now, in layer 2 for example looks at above image

 

[Tisor]

Arno, what you can see in the pic is a bit more than 1cm. Comparing with another scenery producers, say Simwings, FlyTampa... In their airports, the helicopter don't sink or at least it is not appreciable. That's why we are strugglering ourselves trying to figure out how do they do it.

 

[arno]

I think the fs2002 techniques are still more common then the p3d v2 mdl files, so most likely other developers use that.

 

[Peter Hornfeck]

P3D groundpoly are not easy, working on this one week. Informations are not at one place, so difficult to find.

This are the problems I had:

1. Texture Lights are not working above non P3D Groundpoly.
2. Shadows are only visible at layers 17 and higher, below, aircraft will not have any shadow.
3. MCX with P3D option in GPW very often did not make a bgl file, errors occur. Here I read, disable Slice and Group Polygons in GPW, and this helped, I get the needed P3D GPs.
4. The GP I made first, was at layer 16, to high above the ground of the airport.
5. With sketchup I made a box, 80 cm high, with a scale-texture, 80 cm. Placed on the runway (Layer 16), the box was only 63 cm visible. So I calculate this:

MCX GPW add 1 cm for a ground layer to prevent flickering. It seems for every Layer also 1 cm is added. Layer 16 = 1 cm + 16 x 1 cm = 17 cm above the ground.

Is this something caused by GPW? For FSX are all GP 1 cm above the Ground, independet from Layer I choose? For FSX normally I take layer 8, 12, 16 and 20. It seems they all at same altitude. And no flickering.

I will try to make P3D groundpoly 17, 18, 19, 20 and the altitude I will decrease in this way:

Layer 17 = Altitude - 17 cm
Layer 18 = Altitude - 18 cm and so on

Next I will report it's flickering or not.

 

[arno]

Hi,

In the P3D output the polygons get a zbias material attribute assigned. This gives them a different priority when rendering, but from what you write it seems LM might have implemented it as a shift along the normal, so that the polygons get higher. This is a way to handle the zbias values. For FSX the GPW only adds 1 cm indeed to prevent flickering and the rest is done with the FS2004 style layers.

 

[Peter Hornfeck]

Ok, so far, the results:

Layer 17 is at same altitude as before, 17 cm above the runway. As expected, it is not MCX, which is done by Arno
Set altitude to 0, the layer is not visible. Bad bad bad bad bad

BUT I found it

Here how I try to do it:

1. Using normal layers without the P3D settings.
2. All layers should be higher than 16 if they should receive shadows from airplanes
3. And now the most important, change transparency of textures.
- 98% -> the Centerline lights are visible, but not bright
- 80% -> Centerline lights are very bright.

At higher transparency settings, the ground is shinning through the layer, but I will use the normal Runway-surface and taxiway-surfaces and use them to make the runway looking better.

 

[Peter Hornfeck]

NO NEED for this, my fault, found in other discussion:
ADD 0 LOD for the lights is solution


Finally it works fine. I use some layers, all made with GPW FSX.
Day Textures like before. But I add night textures with 80 opacitiy/20 transparency. This way, all lights are very bright and clear.
The layers do not flicker and the opacity/transparency of the layes do not summarize and change the lights. Using 1 layer with 80% and a second above with 80% didn't change the lights. So I use layers for runway, taxilines, dirt and this kind of things. The lights are fine during night and dusk.
In ADE I set all groundpoly to not draw surface, so they do not shimmer through the ground texture of my poly. And because I only use the transparency during night, the ground can not seen by night also and day is not important, because the day textures are not transparent.

 

[GaryGB]

Hi Peter:

Thank you for sharing with us, the results of your innovative and successful testing.


Would you please consider posting some labeled screen shots as a "worked example" to illustrate the above process you used for P3D G-Polys ?


Thanks in advance for any additional info you might share here at FS Developer with other readers that are trying to learn how to work with P3D.

GaryGB