I've not had much luck understanding the new Zbias layering. While it is rendering correctly I'm concerned about not having any control over the layers like we had with ASM layering. In the image below, i've been trying to get the taxiway markings to render below the runway. With the taxilines set to -2 & the runway at -20, the lines should render behind the runway right?
I'm using Prepar3D v3 SDK 3.3.5.17625 & Max2015. I think its setup correctly. I get the same issues going through Arno's MCX.
Does this Zbias layering even work for anyone?
My Max model setup is very simple for this test. Two objects both using a multisub material with two material IDs.
Any help would be appreciated.
George-Flytampa wrote:I've not had much luck understanding the new Zbias layering. While it is rendering correctly I'm concerned about not having any control over the layers like we had with ASM layering. In the image below, i've been trying to get the taxiway markings to render below the runway. With the taxilines set to -2 & the runway at -20, the lines should render behind the runway right?
Hi George,
It's the other way around.
Higher neg numbers mean higher priority.
According to the SDK, The more negative the Z-bias, the later in the process it will draw. So it is setup to render the runway last & hide the markings.
Anyway, its doesn't matter as reversing the numbering makes no difference. So i'm wondering if this Zbias layering even works for anyone?
Hi George, I've got quite a few airports working with the Zbias system.
I've reviewed your hi res material settings and will note a couple items.
My textures that use Z-test alpha checked are set to GreaterEqual, 128 and these textures also have the Z-write alpha checkbox checked. These textures have a 1 bit alpha.
Textures with no alpha do not have the Z-test alpha checked and do not have Z-write alpha checked.
I am curious if these settings changes affect your test.
One other issue I have run into is a little harder to explain. I've seen large portions of aprons ignore my z-bias sometimes if the geometry has possibly corrupted or something in 3dsMax. Splitting an apron into 2 pieces to find the bad geometry or reset the transform and scale to help identify these issues.
I thought you'd nailed it with the resetting of the transforms as that is a routine problem with some non zbias ground elements. Unfortunately it didn't seem to make any difference.
It must be a problem my end. SDK setup or version of MAX (2015). It's nice to know the zbias feature does work so I'm not wasting my time. I just can't seem to get any reaction from changing the Zbias values under any scenario.
How are your models & materials setup? Do they have to be separate objects or collapsed into a single object?
I was also curious to know if the Zbias sorting works between separate bgls?
George, I'll try and spill all the details without a screenshot.
My runway model with the zbias materials is a separate .mdl from the buildings. Both .mdls are stored in the same .bgl, not in a library .bgl. I haven't tried mixing zbias levels from multiple .bgls in the same place.
I have collapsed all the geometry with the same material down to one mesh, one mesh per material. There are 16 meshes and I have the zbias ranging from -1 for the lowest older surfaces through -10 for the markings and oil etc. Not everything overlaps. I'm using a detail map in my example i'm looking at now and have used specular and normal in the past too without problems.
All the meshes are on the same z plane to begin with, flattened to 0 and then I apply a slope to fit the curved earth "flat" airport area. I can't see from your screenshot that this is the case and I am assuming they are planar.
I'm not using platforms in the geometry, I'm using surfaces drawn in the airport .xml which I make transparent. Let me know if that sparks any ideas to try.
I'm using 64bit 3dsMax 2012. I have a 3dsMax 2015 I can try to verify too.
