Level Of Detail (LOD) Ranges: Difference between revisions

+- Minor cleanup; +- Updating some values; + Related wiki article and source files; cat: Rendering
No edit summary
(+- Minor cleanup; +- Updating some values; + Related wiki article and source files; cat: Rendering)
Line 1: Line 1:
'''Level of detail''' ('''LOD''') '''ranges''' are controlled several properties in FlightGear, with the below default values.


Level of Detail (LOD) is controlled by three properties in FlightGear, with the following default values:
== Scenery ranges ==
 
{{note|The LOD ranges are only set during the scenery loading process. Therefore a scenery reload may be required to change the currently loaded tiles.}}
{| class="wikitable"
{| class="wikitable"
|-
|-
! Property !! Default !! Description
! Property !! Default !! Description
|-
|-
|sim/static-lod/detailed||1500 M||All objects (buildings etc) display withing this range.
| <code>sim/static-lod/detailed</code> || 1500 m ||All objects (buildings etc) display withing this range.
* Building meshes using OBJECT_BUILDING_MESH_DETAILED (Additional 1414m is added as these meshes are 2000mx2000m)
* Building meshes using OBJECT_BUILDING_MESH_DETAILED (Additional 1414 m is added as these meshes are 2000 x 2000 m)
* The actual visibility range is randomly distributed from /sim/static-lod/rough to twice /sim/static-lod/rough, to reduce apparent "popping".
* The actual visibility range is randomly distributed from <code>/sim/static-lod/rough</code> to twice <code>/sim/static-lod/rough</code>, to reduce apparent "popping".
|-
|-
|/sim/static-lod/rough||9000 M||terrain and non terrain objects will be displayed within this range, as follows:
| <code>/sim/static-lod/rough</code> || 7500 m || Terrain and non terrain objects will be displayed within this range, as follows:
* Objects listed in scenery STG files using OBJECT_STATIC or OBJECT_SHARED verbs
* Objects listed in scenery STG files using OBJECT_STATIC or OBJECT_SHARED verbs
* Random scenery objects
* Random scenery objects
* Random trees
* Random trees
* Random buildings
* Random buildings
* Building meshes using OBJECT_BUILDING_MESH_ROUGH.  (Additional 1414m is added as these meshes are 2000mx2000m)
* Building meshes using OBJECT_BUILDING_MESH_ROUGH.  (Additional 1414 m is added as these meshes are 2000 x 2000 m)


The actual visibility range is randomly distributed from /sim/static-lod/rough to twice /sim/static-lod/rough, to reduce apparent "popping".
The actual visibility range is randomly distributed from <code>/sim/static-lod/rough</code> to twice <code>/sim/static-lod/rough</code>, to reduce apparent "popping".
|-
|-
|/sim/static-lod/bare||30000||Only terrain after this point
| <code>/sim/static-lod/bare</code> || 21000 m || Only terrain after this point
|}
|}
NOTE: The LOD ranges are only set during the scenery loading process. Therefore a scenery reload may be required to change the currently loaded tiles.


== AI/MP ranges ==
== AI/MP ranges ==
AI/MP models (other models that aren't being flown/operated by the user) have two models. The first of these is the low detail (or fallback) model, which can be defined by an model developer (sim/model/fallback-model-index) as one of the values in $FGData/AI/Aircraft/fallback_models.xml. When there is no fallback model defined for a model the blue-yellow glider will be used.
AI/MP models (other models that aren't being flown/operated by the user) have two models. The first of these is the low detail (or fallback) model, which can be defined by an model developer (<code>sim/model/fallback-model-index</code>) as one of the values in <code>$FGData/AI/Aircraft/fallback_models.xml</code>. When there is no fallback model defined for a model the blue-yellow glider will be used.


There are three properties that control the operation of the LOD ranges for  
There are three properties that control the operation of the LOD ranges for  
Line 33: Line 32:
! Property !! Default !! Description
! Property !! Default !! Description
|-
|-
|/sim/static-lod/aimp-range-mode-distance||false|| When true the distances in the following aimp- properties are considered to be the distance from the camera.
| <code>/sim/static-lod/aimp-range-mode-distance</code> || false || When true the distances in the following aimp- properties are considered to be the distance from the camera.
|-
|-
|/sim/static-lod/aimp-detailed||400 (pixels)||This property works differently depending on the range mode.  
| <code>/sim/static-lod/aimp-detailed</code> || 400 px || This property works differently depending on the range mode.  
* In pixel mode it is the size (in pixels) of the object on screen. When greater than this amount of pixels the detailed model will be used
* In pixel mode it is the size (in pixels) of the object on screen. When greater than this amount of pixels the detailed model will be used
* In range mode it is the distance from the viewpoint, when within this range the detailed model will be used.
* In range mode it is the distance from the viewpoint, when within this range the detailed model will be used.
|-
|-
|/sim/static-lod/aimp-bare||0 (pixels)||This property works differently depending on the range mode.  
| <code>/sim/static-lod/aimp-bare</code> || 0 px || This property works differently depending on the range mode.  
* In pixel mode it is the maximum size (in pixels) of the object on screen. When below this amount the low detail (fallback) model will be used. It is possible to set this to a non-zero value to stop drawing anything when close (although quite why anyone would want to do that is beyond me), and thus a value of 0 is the expected usage of this in pixel mode.
* In pixel mode it is the maximum size (in pixels) of the object on screen. When below this amount the low detail (fallback) model will be used. It is possible to set this to a non-zero value to stop drawing anything when close (although quite why anyone would want to do that is beyond me), and thus a value of 0 is the expected usage of this in pixel mode.
* In range mode it is the distance from the viewpoint, when above this distance the low detail model will be used.
* In range mode it is the distance from the viewpoint, when above this distance the low detail model will be used.
|}
|}


== Model interiors ==
== Model interiors ==
Line 50: Line 48:
! Property !! Default !! Description
! Property !! Default !! Description
|-
|-
|/sim/static-lod/aimp-interior||200||range at which to display the model interior (when the model has defined a mesh as being the interior
| <code>/sim/static-lod/aimp-interior</code> || 200 m || Range at which to display the model interior (when the model has a mesh defined as being the interior).
|}
|}


== Related content ==
=== Wiki articles ===
* [[FlightGear configuration via XML]].  See in particular the section [[FlightGear configuration via XML#Adding your own settings|Adding your own settings]].
=== Source code ===
* {{fgdata source|path=defaults.xml}}. Do not change this file, rather follow [[FlightGear configuration via XML#Adding your own settings|these instructions]].
* {{simgear source|path=simgear/scene}}


== References ==
[[Category:Rendering]]
{{Appendix}}