tree leaves - opacity vs. refraction

[rivoli]

it looks very good. as you say opacity mapped plants can render quite fast (had to do a bit of optimization on xfrog ones lately), but never thought of using mapped grass till now.

six for individual grass blades

and I wouldn't have thought of scattering around single blades of grass for sure

[voltron7]

Looks pretty good, I am intrigued by this method. Now I am going to do some of my own tests with opacity and grass and my onyx tress.Aldaryn, could we see a wire of that crop please?

[Aldaryn]

cubiclegangster: Well, at first I was on the same opinion. I remembered opacity mapping things in vray was a render time killer, so I sticked to modelling everything, but as a part of the refreshment of our foliage techniques I started to experiment with opacity mapping eveyrthing, and it worked. The image I posted has approximately five miilion grass planes per view and the memory footprint was way smaller then displacement, the rendertimes were much, much, much faster and the overall look was so better. Of course, you need to get used to working with it. I've attached the same image here, so you'll be able to see what I'm talking about. I don't know why you can't see it, we never had any trouble with our host.

rivoli: Yeah, using one plane per blade was a long shot for me like using opacity mapped places to grass in the first place, but turned out pretty well in the end. I was actually surprized to see it working and rendering in reasonable times...

voltron7: Ah, sorry no wire from that shot atm.

Best regards,
A.

[Aldaryn]

And dynaman sorry for hijacking your thread. Any chance you're using standard max shaders instead of Vray's? My collague said he last saw something similat to this back in the scanline days.

Best regards,
A.

[Pixelab]

I did some tests on the influence of filtering and/or refraction on my blog

You may find the results intresting (maps were B&W pngs)

It might also be an idea to redo them with loads of trees for example... I'll think about it

Aldaryn : your result is impressive ! I was also thing of this method to map a insane project i'm doing

[Neilg]

cubiclegangster: Well, at first I was on the same opinion. I remembered... etc

Thanks for re-uploading the image, think i'm going to have to give this method another try now.
After a massive amount of r&d into grass a while back I opened up displacement a lot more for mid to long range stuff, but there have been a few times when I couldve done with edging like that in a still.

[dynaman]

wow - that is some impressive landscaping detail.

just wanted to bring it back to my original problem...is it safe to assume that opacity mapping is the way to go when rendering alpha channeled geometry?

i tried re-creating the leaf material from scratch, and now it is rendering fine. i discovered that i had unchecked double-sided in the old material and that was what was causing the problem of the leaves appearing semi-transparent.

guess it's problem solved, albeit in a very roundabout way...

[bob-cat]

->Dynaman - yes round-about but hey the grass pics were worth it.
I did have a another idea a bit late though - if you were using relfection on the leaves you might have to alpha/mask the reflection with the leaf also.
And..... your trees look great, are they onyx with plane leafs?

Cheers