I posted this in my wip thread, but might as repost it here if it’s ok, more people may come across it here. This is quick start into how I do my vegetation, but most of it is bit old (it desperately needs vertex colors and instance variation),
so I might learn and update it during this project and then do a full video on it.
Thanks Juraj, this helps a lot. Seems that I have to step up on my veggy materials. 
Even basics helps the most :- ) Good normal map with strong relief and saying no to “evermotion green” color (toxic level of brightness and saturation)
Thanks for sharing. I have never tried the front back map with darker and lighter shades. Will give it a try. Quick question though; what do you do for the branches? Also any recommendation for pine trees?
I will continue with the branches and trees :- ) But not today, need to do some client’s review that suddenly came.
Very usefull, thanks! Ground cover is bbb I guess? Tree is made in house?
Thanks a lot Juraj… always a pleasure to follow your advices !
Hi,
This morning I saw that Evermotion is finally providing Corona models and tested the free sample of their tree collection. Must say that they did a pretty good job on the shading part. It has some good similarities of your approach and hopefully this will set a new standard. Looking forward to see your approach on barks and branches (turbosmooth, noise and\or displacement if I saw it correctly at SOA 2014 )
Yes by Bertrand, I am even writting it in the tutorial pic :- )
Yes that’s it :- ) I will post that too. I spent some time figuring out how to effectively merge scanned mesh (not just texture) but that didn’t provide any fruit yet.
Appreaciate the share! Though I must say the translucent hue some of your groundcover plants have leans a bit too much to the blueish green, in my opinion It´s a subtle thing but it´s the sort of green that plastic plants often have. Then again it might just be a regional thing and that´s how some plants look where you live
I don’t think so.. all the translucency slots are extremely yellowish, and looking at the picture, the blue-ish tint you see is top part of leaf, reflecting blue sky/shadows. You can’t even see much translucency in the groundcover at this angle. PS color-picker doesn’t reveal any blue either..
Neither do I live anywhere where these plants exist…
The translucent part has no blue tint at all… use PS color picker. Since that exact plant has very thick leaf, the translucency is more minor, and thus takes most of the color from the diffuse, rather than translucency. Which is how it should be.
Saturation yes, it’s over-done, but that is post-production on my side. Went to far in ‘vivid’ look. It’s was test merely. But the only blue is in sky reflection on top part of leaves.
The attached example is quick google photo, which I didn’t touch. Yet it matches the values, the images are similarly post-produced. Both Translucency are exact rgb match.
You also embedded your crop with AdobeRGB profile, while my original picture has sRGB (for which I have my monitor calibrated exactly, despite being wide gamut capable, U3014 ), so it’s more saturated than should be.
Unless your browser is color-profile capable (only Mozzila as far I am aware), you’re looking at my image incorrectly.
That might be the case here. Damn these color profiles.. anyway, thanks for taking the time explaining and I hope to see more of your progress!
I just realized that I never thanked you for sharing some of that awesomesauce. Thank you Juraj, you’re the man!
Thank Juraj for this tutorial!!
I have a question about the refelction maps.
A lot of people use them and have great results. But they tend to recreate something that isn’t there. Don’t they?
As you look to leaves closely the reflection (except for small parts and veins or dried leaves) is pretty much uniform. Still we project reflection maps to create less and more reflective parts on a leaf.
It enhances the feeling of the 3d ripples and deformations of the leaves but also tend to distort the reflection of the leaf as a whole. Especially if you look from a distance.
This is even worse if the diffuse maps have highlights too.
I haven’t found a better way to shade leaves though. So it is centainly not a comment on your setup! I was just wondering.
Yeah I completely agree there.
Imho their purpose is correct, to vary reflectivity, but glossiness map should be enough to do that. To use it further in spec slot to enhance the same effect means the map isn’t strong enough, or they’re indeed creating something that isn’t there to boost the look.
But it’s true it ideally shouldn’t work that way..imho low glossiness should clamp specular reflection far more than in does currently in Corona, but I don’t know
kind of math that should be. Only thing I know, is when I create material in Unreal, Marmoset, etc.. which all use GGX as well, high rougness (low glossiness), give me almost diffuse look. In Corona, it gives me slightly “shiny” look instead.
So yes, I also break my own rules, and do use reflection map, when it gives me visually nicer result. Or I often clamp reflection to lower number as I go to lower glossiness (like 0.5 for 0.5..).
It’s just that I am not happy with such workflow, because I can’t be sure which version is physically correct. The more you tinker with specularity in materials, the less they will work cohesively in the whole scene to plausible result. Of plausible doesn’t mean visually interesting, I am not trying to stress the photorealistic aspect.
I’ve been aiming to adopt this approach to materials recently - physically based, if I’m safe to call it that - but agree that it seems difficult to work with rough materials in Corona and stick to the core principles as things stand.
Materials with a low glossy value seem to attract an unrealistic amount of reflective fuzz and I’m constantly cheating on the concept to make things look right to me.
I wonder if it’s self occlusion that isn’t being taken into account in the shader. I’m only vaguely remembering this from reading some of that PBM information that was discussed and posted on the forum here about a year ago.
So rough materials viewed at glancing angles should be trapping and obscuring some percentage of specular reflectance. Not sure if that currently happens automatically, or even if it should much.
That’s how I’ve been justifying lowering reflection amounts to myself anyway!
I thought it was interesting that there was the issue with dark edges appearing on rough materials when GGX was first implemented in Corona - that rays of specular reflection were being reflected back into an object.
With very rough materials at certain angles I don’t understand how that was entirely incorrect, even if it was an accidental side effect of the GGX model rather than a developed abstraction of a rough surface.
Perfect, thanks :- ) Didn’t know that.