3d model combined with 3d floor effects model disappear

Azure Agony · Post by **Azure Agony** » Sat May 24, 2008 9:59

Here is the problem:
I use 3d model of steps combined with 3d floor. The 3d model it's only use to show steps (it hasn't got no height or radius and it's nonsolid) the 3d floor is using to fake you could climb the steps (of course alpha channel of the 3d floor is 0). Problem is when you look on it in certains angles the 3d model is DISSAPEARING. It's not happens when I use 3d models without 3d floor).
I shows these all on short movie at adress: http://youtube.com/watch?v=aBMMGVyyl1A

At movie the 3d floor has 200 alpha channel to show where is it located, and I show the 3d model combined with 3d floor (when bug appears) and without 3d floor (where everything is o. k. ).

Here I put DECORATE and MODELDEF:

ACTOR STEPS 23003
{
+NOGRAVITY
States
{
Spawn:
POSS A -1
Stop
}
}

Model STEPS
{
Path "models/MAP_OBJECTS"
Model 0 "STEPS.md3"
Skin 0 "STEPS.jpg"
Scale 0.8 0.8 0.8

FrameIndex POSS A 0 0
}

P.s. Of course it's simple version of this combination but the bug appears too, in full version I use 3d floor for rails too but the problem is this same.
Cheers!
P.s. 2 Oh, I know, Graf you don't interested in 3d models too much but I'm only interested is some way to fix it or not

Post by **Graf Zahl** » Sat May 24, 2008 10:03

A movie is of no use to me. Send me the WAD/PK3 so I can investigate if you want it to be resolved.

Azure Agony · Post by **Azure Agony** » Sat May 24, 2008 10:19

OK, I sent you a file on PM.

Post by **Graf Zahl** » Sat May 24, 2008 10:52

The problem is simply that the actor's real radius is used for visibility clipping. Make it large enough so that the entire model fits into it and the problem should disappear. Also use the +NOBLOCKMAP flag so that it doesn't get affected by any kind of sector movement.

Azure Agony · Post by **Azure Agony** » Sat May 24, 2008 12:54

Yes, I noticed the larger sector resolves that problem but I wasn't sure it (however sometimes I need sector smaller than object or use group of sectors for one object. I'll find some other way to fake these effects).
Great thanks for really quick answer!
Cheers!

Post by **Enjay** » Sat May 24, 2008 13:02

Yeah, this is a "problem" that I have come across myself.

It just means, as graf said, you have to make sure that the sector that you place the object in is visible everywhere you want the model to be visible from. Apparently the same system existed with sprites - ie, they were only visible if the sector they were in was visible - but it was less commonly noticed because of factors like the usual size of sprites.

Sometimes if, like you, I need to make a structure that is composed of quite a few solid sectors, I will make a small hole in the structure and sit the model item in that. The hole will be the same sector as the one surrounding the structure so that no matter where you see the model from, the sector it is in is visible - and so the model gets drawn.

eg, consider the following. The small rectangles would be used as individual steps (eg using 3D floors). The areas coloured green are the same sector (both the surrounding bit and the small square in the middle) and the orange thing would be the item that the model was attached to. Because the green sector could be seen from wherever you were looking at the steps from, the model would always be drawn. The player will never fall down the small hole because it is far too small for him to fit through.

Azure Agony · Post by **Azure Agony** » Sat May 24, 2008 13:56

I made some changes and now combined models with 3d floor and 3d model doesn't disappear.
p.s. Of course for screenshots I didn't make zero alpha for 3d floor to show where they are located