[LODs] ~ Transition between grass' LOD0 and LOD1 is extremely evident, how to improve it?
triangle
I'm studying foliage, more precisely I'm onto grass at the moment.
As you can see, LOD0 is quite high poly and doesnt use any transparency masking, it's just plain meshes.
Let alone that it needs some tweaking because of the excessively high polycount, now I'm testing LODs and what you see in the distance is LOD1 kicking in.
Bloody awful, huh? =p
How may I make transition between LOD0 and LOD1 less noticeable?
LOD0 has patches of grass composed of single strands, while LOD1 has just a handful of the same strands plus a couple of crossed cards.
LOD0 has it all, color/normal/AO at 512px, while LOD1 only has color and normals with a resolution of 256px.
I expected normals on the cards (I've made a couple of projections of LOD0 onto simple planes) to supply the right amount of light variance to resemble the 3D strands, but the difference is abyssal, all but unnoticeable.
How may I make the transition less evident?
What kind of "reductions" should I implement when crafting LOD1 (and subsequent)?
A single grass strand is composed of 13 triangles, the circular patch is 60cm in diameter and hosts 269 strands (hence the high polycount).
Maybe I could reduce the number of triangles per strand to 11 or even 9 (unlikely), but more likely I'll use less strands.
Anyway, how may I move from such a high poly LOD0 to a less heavy LOD1 without the transition being too evident?
I was thinking of just reducing the number of strands while making them "fatter" (scaling up over X and Y) from LOD0 to LOD1, and then again from LOD1 to LOD2.
Do you think this would work?
PS: if anything I've typed doesnt make much sense, be aware that it's almost 3:30am and I've been working on this thing for the last....9 hours, apparently!!
Eventually I'll sort it out tomorrow. In the afternoon.
As you can see, LOD0 is quite high poly and doesnt use any transparency masking, it's just plain meshes.
Let alone that it needs some tweaking because of the excessively high polycount, now I'm testing LODs and what you see in the distance is LOD1 kicking in.
Bloody awful, huh? =p
How may I make transition between LOD0 and LOD1 less noticeable?
LOD0 has patches of grass composed of single strands, while LOD1 has just a handful of the same strands plus a couple of crossed cards.
LOD0 has it all, color/normal/AO at 512px, while LOD1 only has color and normals with a resolution of 256px.
I expected normals on the cards (I've made a couple of projections of LOD0 onto simple planes) to supply the right amount of light variance to resemble the 3D strands, but the difference is abyssal, all but unnoticeable.
How may I make the transition less evident?
What kind of "reductions" should I implement when crafting LOD1 (and subsequent)?
A single grass strand is composed of 13 triangles, the circular patch is 60cm in diameter and hosts 269 strands (hence the high polycount).
Maybe I could reduce the number of triangles per strand to 11 or even 9 (unlikely), but more likely I'll use less strands.
Anyway, how may I move from such a high poly LOD0 to a less heavy LOD1 without the transition being too evident?
I was thinking of just reducing the number of strands while making them "fatter" (scaling up over X and Y) from LOD0 to LOD1, and then again from LOD1 to LOD2.
Do you think this would work?
PS: if anything I've typed doesnt make much sense, be aware that it's almost 3:30am and I've been working on this thing for the last....9 hours, apparently!!
Eventually I'll sort it out tomorrow. In the afternoon.
Replies
Are you sure that's the best solution? =o
Is there any tweaking I should do to improve the performance of UE4 embedded LODs system? =0
Are there "best" values for LODs?
Like the amount of LODs, distances (screen size, now), triangles percentage, etc etc...
And what does "silhouette" do, exactly? =0
Imo it's insane amount of geometry for the grass only Plus it would become more on pair with similar Fresnel effect we see in the grass by our own eyes usually because or different view angle
I've used auto-LODs as @Obscura suggested and voila:
http://d.hatena.ne.jp/hanecci/20150712/p4
LOD1, instead, can be decimated and horizontal meshes can be eliminated, since vertical ones would hide the terrain for good.
But now I'm not surprised anymore....you should see what Simpligon makes of my grass strands on LOD3! ^^'