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Is LOD really dead?

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Hey Guys I have just read "Though, a lot of people now will say that, for games, LOD is dead. You will spend more time dynamically modifying the terrain then a GeForce card would spend rendering it at full detail (provided that one still does gross frustum culling)." Is it true? It seems that Need For Speed 2,3,4 use adaptive meshes,but NFS 5 do not. Is LOD really dead? Thank you.

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LOD has issues with Pixel shaders that are not easily solved. That is what I believe is driving most developers away from LOD.

My 2 cents
Cheers
Chris

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I''d actually say most developers are increasing the amount of LOD in their code...

...but wasting less time at the per polygon level. LOD for lights, LOD for bones, LOD for shaders, LOD for audio sources, LOD for terrain tiles, LOD for textures etc etc are all still extremely relevent.

In the context of the quote, using something like ROAM and generating 1000s of single tri-fan renders per frame is just about the worst way to treat T&L hardware.
But there are suitable alternatives, usually still by avoiding doing any work per polygon.

--
Simon O''Connor
Creative Asylum Ltd
www.creative-asylum.com

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for terrain some form of CLOD makes a huge performance increase..at least for what i have which is like 1000x1000 vertices.

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LOD is definitely not dead. BTW, you probably meant to say CLOD, which is realtime computing of LOD. Old algorithms like ROAM are dead, because they compute per polygon stuff that takes to long to be efficient.
Newer algorithms are still used, like Geomippapping is good for terrain. It just computes the lod for patches of land based on how far they are and what angle they are viewed from.

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Thank you.
robirt,then whether
Thatcher Ulrich''s Continuous LOD Terrain Meshing Using Adaptive Quadtrees
(http://www.gamasutra.com/features/20000228/ulrich_01.htm)
is out of date?

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quote:
Original post by mictian
for terrain some form of CLOD makes a huge performance increase..at least for what i have which is like 1000x1000 vertices.


Yup, as long as the output of your CLOD is a hardware friendly sized batch rendered in a single call (assuming T&L on the chip rather than s/w).

If you aren''t doing much else per frame its easy to have your results obscured too -: if your brute force code was bound totally by vertex upload cost (as it would be with 1000x1000), even a bit of ROAM code would improve that *a lot*, and end up driving the chip at say 2% efficiency and be showing "**big** improvements" in frame rate simply by not being vertex upload bound - still doesn''t mean its efficient though :o).

- its all relative -
- don''t touch the vertices -



--
Simon O''Connor
Creative Asylum Ltd
www.creative-asylum.com

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for smaller landscapes, yes, lod is more or less dead. but if you for example want to simulate a whole planet, (spherical) roam is great, and really speeds up much.

it all depends on what you do. you can do more bruteforce than you could some years ago, i do agree. but till now there is no real lod in hw. okay, dx9 has it, lowres meshes with displacementmapping, addaptive tesselation on them. never tried to get that working, but it should be holy fast...

"take a look around" - limp bizkit
www.google.com

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Guest Anonymous Poster
quote:
Original post by davepermen
..holy fast...



Is that faster than evil fast ;-) *grin*

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