[Monty]

I have a Freight Anim of a set of ditch lights and notice that at some angles and when you zoom in with view that the FA disappears from view. This I can fix by increasing the value of Volume Sphere setting in the shape file. The FA is one I downloaded from who knows where so don't know what the correct volume sphere setting should be. Can anyone explain to me what actually is this Volume Sphere thing is. I just increased the value till FA could be seen up close and at all angles. Used a figure of 10 as a straight out guess and all is fine with no obvious side affects. Just curious as I have never seen this before.

[vince]

Hi Monty,

Use ShapeFileManager utility (available in the trainsim.com file library) to de-compress the shape file then edit it with a unicode complient word editor, Microsoft Wordpad is what I use but there are other suitable editors.

And from my notes, an illustration of a typical shape file header:

==============================top of shape file===============================
SIMISA@@@@@@@@@@JINX0s1t______

shape (
shape_header ( 00000000 00000000 )
volumes ( 1
vol_sphere (
vector ( 46.612695 2.9792 37.291229 ) 86.158682
)
)
=======================end of shape file clip=============================
Where is says vector, make sure that the number outside the parentheses it larger by about 2x to 3x times than the first number in the parentheses.
If not, change the last number so it is larger than the first number. If it doesn't go away, keep increasing it.
I've found no harm in increasing the number until the problem goes away.
Re-compress the shape file when done testing.

regards,
vince

[Monty]

Thanks Vince. I had already increased the last number in the shape file and it fixed the problem, however I did not know if I had done any other damage by changing this value. Your advice has cleared the matter up nicely Thank you for your help Cheers

[James Ross]

 Monty, on 30 December 2015 - 02:29 PM, said:

I have a Freight Anim of a set of ditch lights and notice that at some angles and when you zoom in with view that the FA disappears from view. This I can fix by increasing the value of Volume Sphere setting in the shape file. The FA is one I downloaded from who knows where so don't know what the correct volume sphere setting should be. Can anyone explain to me what actually is this Volume Sphere thing is. I just increased the value till FA could be seen up close and at all angles. Used a figure of 10 as a straight out guess and all is fine with no obvious side affects. Just curious as I have never seen this before.

The last value in the "vol_sphere" is the radius of the view sphere, and it is used (in Open Rails at least) to figure out whether the object is in view. We check whether a solid sphere, centered at the object's location, with the given radius, would be visible on screen. We don't use the "vector" at all, which may be a bug.

[Monty]

Thanks James for the explanation. All is well with the FA I had the problem with as I just used Vince's advice and increased the last value to 3 times it's original value and the FA could be seen again at all angles and distances.

[lenglel]

I think the vector is intended to be used as an offset from the shape origin. For example, a track section 100m long needs a volume sphere of 50m radius, UNLESS the vol sphere is centered at the track shapes origin. Otherwise, the shape would disappear completely if the half that was within the vol sphere was obscured by a building or other object. Is your 100m vol sphere got a 200 in that last number? Now you know why.

[Genma Saotome]

I would not be surprised if the three values inside the parens are the location of the center of the model. If that is the case then there is no way from those data to estimate a correct value for the view radius value.