Rockliffe

LOD & Autogen Draw Distance what's the difference?

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I have this question over at the P3D forum, but have not received any reply. Anyone?

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Lod radius only deals with the high res ground texture ring.  Autogen draw distance is what it says. It determines how far out the autogen draws. 

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1 minute ago, GHarrall said:

Lod radius only deals with the high res ground texture ring.  Autogen draw distance is what it says. It determines how far out the autogen draws. 

Hi Glenn, thanks for the reply. But what do you mean by 'high res ground texture ring?'

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Although I performed these tests with v3.2 the results are still valid (but v4 pushes the higher resolution rings further away from the pilot).

 

https://www.avsim.com/forums/topic/485019-v32-scenery-lod/#comment-3387694

 

Basically the coloured rings are showing how as you get father away from the pilot the resolution of the texture, i.e. it's crispness, reduces. Nearby the resolution of the tiles that are loaded by P3D is 1024x1024, next ring is 512x512, etc.

 

The autogen draw distance is independent from these rings, I.e. you could set terrain LOD to its lowest setting (low resolution rings) but have autogen to the horizon if you wanted.

 

HTH

andy

boez

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It's always been my understanding that LOD was the distance around the aircraft, at any one point, that autogen is drawn. The bigger the number, then the further away from the aircraft that autogen is drawn. What you seem to be suggesting Andy, correct me if I'm wrong, is that in P3D, LOD refers to the terrain texture, where autogen distance refers to exactly what it says. If so, then it has all changed?

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Right.  LOD is not the distance of autogen, only ground texture sharpness.  Typically it spans out in the form of squares.  There's probably a picture in google image search.

FWIW it has always been this way - Level of Detail has always been ground texture sharpness around the user aircraft.

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What can be confusing is that the term LOD is used in many variables! It is just a generic term developers use to describe a 'quantity' that has more than one setting.

Level Of Detail can apply to the slider which controls the terrain or the complexity of a model or the placement of autogen. 

So LM have a LOD slider in the settings page which controls the terrain detail (and anyways has done since FSX days and before) and it is this that I'm referring to in my post. But the config file the has an entry which controls the LOD of the autogen and in this case LOD refers to how much autogen is loaded per 1km tile but *not* at how far that loading occurs. That is done by the autogen distance slider. So nothing has changed.

 

A further example would be LOD used in an AI model, a lower LOD when the AI is at distance as there's no point in loading more detail than necessary.

 

 

Edited by boez
Clarification

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...and then there is also LOD in mesh specifying how many elevations points there are per horizontal distance in the x,y directions. I don't know what the exact definitions though.

Ted 

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Well, well, I learn something new everyday! :wink: Thanks guys.

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Specific to Autogen Draw Distance from Beau Hollis:

Our default draw distance of medium is equivalent to v3's max draw distance which is 12km. At this setting, P3D must load about 450 square km of buildings and trees. At the highest v4 UI setting for draw distance, you get a 30km radius which translates to about 2800 square km of autogen data. (roughly 6x the work done in v3). Similarly the high resolution terrain texture option increases the native resolution from 256 to 512 which translates to 4x the work and 4x the memory usage related to terrain textures.

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14 minutes ago, B777ER said:

Specific to Autogen Draw Distance from Beau Hollis:

Our default draw distance of medium is equivalent to v3's max draw distance which is 12km. At this setting, P3D must load about 450 square km of buildings and trees. At the highest v4 UI setting for draw distance, you get a 30km radius which translates to about 2800 square km of autogen data. (roughly 6x the work done in v3). Similarly the high resolution terrain texture option increases the native resolution from 256 to 512 which translates to 4x the work and 4x the memory usage related to terrain textures.

And still many do not understand why they get black squares or slow loading textures when they have sliders pegged.

Vic

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11 hours ago, vgbaron said:

And still many do not understand why they get black squares or slow loading textures when they have sliders pegged.

Vic

I feel addressed, so a little side note: the slow loading textures resulting in black buildings was "introduced" with v4.1, it was not like this in v4.0. So, no, it is not linked to the increased draw distance of autogen and also not linked to the increased texture resolution loaded...

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You were not addressed at all, just a general comment. However, the black buildings have been around since FSX and most certainly are linked to autogen and draw distance and anything else that takes cpu cycles. Just because it was "introduced" for some in 4.1 just means that something else was added to the mix.

Vic

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