Distance to Reference Point Question

#1
Should an object with a distance condition affect frame rates even when it is not rendered?

Here is the reason I ask. For my airport project I created a library of a couple objects made up of simple textured planes to create the illusion of grass. The intent is to place these models along the taxiways. See http://www.fsdeveloper.com/forum/threads/cyqr-regina.430084/page-2#post-686949. I did this on the theory that only a very limited number of the objects would be rendered at one time, limited by the distance to reference point condition put on the models. The goal was to keep the frame rate hit at a minimum. With this idea in mind I placed many hundred copies of the objects. The idea seemed to have a lot of promise because the frame rates seem to be hardly effected as the aircraft rolled along the taxiway. However, the bgl that contains all those hundreds of placements does have negative effect when the airport is viewed from a distance (for instance, on approach) well beyond the distance condition. In this case about a 10 frame per second negative effect which is a problem. When I remove the bgl the frames come back up so I know this file is causing the drain. From this observation I gather that the bgl with all the object placements takes up processing resources regardless whether the object is rendered. Can someone confirm this for me?

Greg
 

arno

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#2
Yes, checking the condition if the object should be rendered or not still costs some performance. So especially with a lot of instances you'll notice that.
 
#3
Thanks for that response Arno. I guess it is back to the drawing board to find a happy balance between detail and performance!
Cheers,
Greg
 

arno

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FSDevConf team
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#4
Or try to group nearby objects in one mdl. So you have groups of grass to place.
 
#5
Thanks. I think that will have to be the go-forward plan if I decide to keep grass in the scenery. Still learning after all these years!

Cheers.
 
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