FPS drop when looking at horizon

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Philippe Renon Philippe Renon
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FPS drop when looking at horizon

Hi,

After upgrading to master osgearth and osg, I am seeing a major FPS drop when looking at horizon.

The use case is similar to what a TPS shooter would do. The camera is sitting behind an object, the object is close to the ground. So the camera is looking at the horizon most of the time.

I got help in past to get this working. I am using LogarythmicDepthBuffer to avoid Z-fighthing when looking at the object up close.
And, more importantly, I am tweaking the lod settings to avoid tile clipping near the camera.

    <options>
        <terrain first_lod="0" min_lod="20" />
    </options>

The FPS drops very badly when rotating the camera as the horizon come into view.
I think the issue comes from my lod settings which causes over tiling at the horizon.
What would be a better way to avoid clipping of tiles.

Here is a screenshot that should provide some information:

gwaldron gwaldron
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Re: FPS drop when looking at horizon

I am not able to reproduce this. Can you provide an earth file and/or viewpoint? Is it possible you are running out of GPU memory and thrashing the GPU?
Glenn Waldron / Pelican Mapping