Jump to content
Search In
  • More options...
Find results that contain...
Find results in...
The Ultimate DooMer

Visplane limit

Recommended Posts

For Doom, Doom 2 and Heretic, it's 128, but for Hexen, it was raised to 160.

Share this post


Link to post

I got it from this line from r_local.h:

#define	MAXVISPLANES	128

Share this post


Link to post
The Ultimate DooMer said:

I wouldn't say so...unless my definition of visplane (each floor or ceiling with unique properties) is wrong. (and it probably is, given that I vaguely know it)

That's not exactly it. In fact it's possible to get a visplane with only two types of sectors, and fredrik said it may be possible with just one.

I don't know the exact definition but I've skimmed over it and it's pretty complex and weird stuff.

Share this post


Link to post

Yeh, check the BSP 5.0 docs. If I understand it correctly, every area with unique floor/ceiling properties and unique height is a visiplane. Areas you can't see don't count.

Share this post


Link to post

Is that 'area' as in an area of the grid? (say, 128x128) As I got a visplane crash on my Plutonia II map and I'm sure I only had about 3 (very large and complex) sectors, two smaller (but identical) ones and a couple of doors with identical properties on show. Which could explain why it always crashes when you're looking out over a large area, even if you're not viewing any extra sectors compared to standing near a corner.

PS. All sector properties count here, not just flats and heights.

Share this post


Link to post

sector is more exact than 'area', it's not related to the physical size of any sector but the number of sectors visible with differing properties (light level, special, ceiling and floor texture).

"I'm sure I only had about 3 (very large and complex) sectors" er you have 3 complex rooms comprising of lots of individual sectors. If you can see these at the same time thats the culprit.

Share this post


Link to post
Nanami said:

and fredrik said it may be possible with just one.

The origin of this "discovery" was a room I had made which would VPO although there was only about 10 actual visplanes. I eventually caught cph (PrBoom developer, maintainer of BSP) on IRC (harder than it sounds, at times he's more dead than Julian) and asked him about it. The answer he gave was that the large amount of solid pillars which was present in the room was too blame, since it created too many on-screen segments or something. I haven't tested, but it should be possible do a one-sector VPO room in that way.

Share this post


Link to post
Fredrik said:

I haven't tested, but it should be possible do a one-sector VPO room in that way.

I think there's a Boom demo wad (maybe on the TeamTNT page?) that uses a shitload of bars to demonstrate that Boom does not have a problem with visplanes.

Share this post


Link to post

Yeah, I think you can get that one sector to happen, too, but that method of overflow is far less common. (I think.) Now that I think about it, I think visiplanes can be split in two (or more) by segs or subsectors. For example, if you had a very large area that counted as one visiplane, a seg might go down the middle and split it in two.

Visiplanes aren't sectors, BSP 5.0 comes with a two sector VPO. Visiplanes are just areas with unique properties. Each floor and ceiling *may* have it's own visiplane, but I'm not sure about that. Anyways . . .

|---|---|---|
|11|22|11|
|11|22|11|
|11|22|11|
|---|---|---|

The areas with the ones are in sector 1, and the twos are sector 2. If sector 1 has a different floor flat than sector 2, this floor area will have 3 visiplanes. Alternately, if they all had the same properties, the floor would have one visiplane. (I think. I'm not positive that that's correct.) Also, if sector 2 was raised higher than sector 1, the part of sector 1 behind sector 2 (the one you couldn't see) wouldn't count as a visiplane.

Phew. Hopefully that's all right.

Share this post


Link to post

There's also a restriction on how many sidedefs there can be on the screen at once to watch out for when editing vanilla.

Share this post


Link to post

Actually, I do have a lot of columns in that area (for scenery, and for blocking line of sight to prevent visplane bugs). Anyhow, I've nearly fixed that bug now, there's only one place it can happen now and I'll have that sorted soon.

The 3 sectors were all split into more than one part, will that raise the number of visplanes on display?

So that means columns can actually harm the visplane limit? (as I've always used them as a remedy in my vanilla wads) Sidedefs are no problem, as they don't cause crashes, only HOM's (and I won't run into trouble with them here).

Share this post


Link to post

Yeah because of the way segs in nodes builders split sectors inta subsectors, thereby spltting visaplanes. (At least I think that's what segs do. :P) Columns really shouldn't be a problem as long as you don't add rediculous amounts in a large area.

Share this post


Link to post

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×