Is there a forum thread which discusses the formulation of a wavy green leaf shader for large leaved plants such as Monstera ?  

I do not want to use an image mapped solution.  

I don't really know how to go about devising a leaf surface with that look of waxiness and organic life-likeness (yikes, not that plastic look !)

Would I have to use special lighting to complete the effect ?  Thanks...

Quote - that look of waxiness and organic life-likeness

You mean scatter combined with fresnel reflection. Pretty much my skin shader.

Is there a free plant prop you would have me demonstrate on other than what comes with Poser? (which is not much)

Specifically, I imported an OBJ version of an SKP item from 3DWarehouse.  It is the Monstera plant (link to page):

https://3dwarehouse.sketchup.com/model.html?id=453f6d287626764498c5858b88d0229e

( I used 32-bit Shade 3D for Unity to import the SKP, and then exported it as an OBJ for Poser).

@BB - the first example without the leaf veins, is more like what I should be using.

Right, back to this.  

Here is my render of the imported OBJ with the default colour carried over from the source files. (Please ignore the notional ground shader).

I don't know what the best way is of getting my PP2 version of the converted model over.  I also recall that sitemail isn't working reliably for you, BB. 

get Dropbox, upload your file, send me a share link, I make pictures, you delete the file

I don't need pp2. Obj is fine. 

I switched to chrome for site mail. 

Quote - Is this the look you're after?

Is this your Skin shader BB?

Looks really good with the plant.

Quote - > Quote - Is this the look you're after?

 

Is this your Skin shader BB?

 

Looks really good with the plant.

Pretty much. It depends on what we mean by shader - is a shader the set of nodes and how they are connected, or is it also the values in all the parameters?

It is mostly the same set of nodes and connections as my basic skin S+B+FBR skin shader, which is also pretty much the same as for any kind of glossy surface - the differences lie in the values and colors you set in the parameters. Also, the bump. I don't use the skin bump here.

So I have many problems with this prop that will limit what we can do.

1. The leaves are one-sided and facing down. Since they have no thickness, scatter doesn't really do its job, which is a big part of the realism of a leaf shader. The facing down part can be dealt with by using Normals_Forward but it's still coming out wrong.

2. The leaves are not UV mapped. Real monstera leaves have veins that need to be indicated in an image map - I can't do them procedurally. Also monstera have some patterning on the leaf tissue that has a specific orientation. Even in a procedural shader, I often use the UV mapping in the procedure to orient the pattern that is generated. With these leaves, I cannot do that.

http://upload.wikimedia.org/wikipedia/commons/f/f3/Starr_080731-9573_Monstera_deliciosa.jpg

http://www.trianglenursery.co.uk/media/14312/Monstera%20Leaves%20Large.jpg

1. The geometry is entirely made of very long, very thin triangles. This is a Poser nono. I'm getting artifacts in my raytraced reflections and shadows that reveal the polygon shapes very clearly.

2. The leaves are flat, not curved like the real thing. The resulting reflections look like it's a plastic mockup of a monstera, not an actual monstera.

I put the same on the stems, but I made the stem color lighter and more yellow.

If your version of Poser doesn't have the Scatter node, replace that with a Diffuse node.

woww.

the first glossy sample looks like it would work for inner mouth procedural, to replace image maps.

i think that's the most organic poser render i've ever seen.

That's a nice shader. Looks good with other colors, too.

And yes, that very first example with the little plants you showed looks amazing !

bill, thx fr leaf shader.  will try it on leaf w/thknss.  xfrog guy gimme alotta freebies, might be useable on some.

Quote - Thank you, BB.

That's a nice shader. Looks good with other colors, too.

And yes, that very first example with the little plants you showed looks amazing !

omg, looks like milk chocolate.  wowwww

feels like i can reach out and eat it.

nomms

Thanks guys. If you do have a color map, use it instead of the Turbulence node and the green color chips should be set to white.

I found some plant online that I'm rendering with this shader + the color map and vein bump map that came with the plant. Will post when it's done. (slow)

feels like i can reach out and eat it.
nomms"

It does, doesn't it ? :-)

I'll send you a sitemail.

That is...quite a difference. :-o

Quote - Here we go. Same shader nodes, except this prop has a color map and a bump map. The color map goes into the Scatter.

 

WOW

Thank you so much for throwing your expertise at the converted OBJ monstera, BB.  I realise it is a very crude model.  The other posts in this thread are valuable for learning purposes, and I am grateful to other commenters here for their inputs.  

nommms chocolate gnome, delicioso  :)

hmm.  is it me being crazy or does the plant in the first pic sort of look like human testicals?

Get your mind out of the gutter! LOL!

Quote - Get your mind out of the gutter! LOL!

tee hee.  well, looking around my room i don't see anything else that makes me think testical.

...

seeing a ruler and desk i think spanking.  if i act bratty maybe i'll get lucky. lol

LOL!

Just wondering - why do you have a color set on the diffuse if the diffuse is turned off?

SreeD preview. I do many highly illogical things with shaders because the system is highly illogical.

Ah ok. I'm not all that well versed in the material room so I wasn't sure if I just was missing something. Cool to know the reason, thanks!

it's like preview-only lites.  mat room:  white colour, intens 1, black diff, black spec.

Bill;

Thanks for the screen shot!  I've been looking to create more realistic leaf texture for my Dryad character.

This image shows what I came up with on the left, and after using your method on the right, replacing the solid color with a image. The left has a bit of a waxier look to it, perhaps a bit much, but it certainly gives me something to work with.

Definitely increased the render time by several hours though...

Quote - Definitely increased the render time by several hours though...

And I can't see any evidence that you're using an HDR environment, which means you can get back a lot of render time by eliminating the (blurred) reflection. The reflection component of leaves is rather low, and without a bright sky will amount to nearly nothing. That's a lot of computes to calculate 0.

On the other hand, if you were doing this in a properly executed outdoor environment, you'd see a huge difference.

Here we go. Same shader nodes, except this prop has a color map and a bump map. The color map goes into the Scatter.

 

Were the leaves of that prop a mesh with volume, or zero-thickness one-sided?

(Yes, I know that this thread is over a year old... but some old threads are like fine wines that have been laid down to mature - they need to be turned occasionally  ;) )

Yesterday I found myself in need of a good leaf shader, and ended up here. The leaves of the ivy I'm using are simple flat trans-mapped squares.

I read bagginsbill's comment about one-sided leaves on page 1 that noted "... Since they have no thickness, scatter doesn't really do its job, which is a big part of the realism of a leaf shader...", so I'm aware of that limitation.

I also noted bagginsbill's comment about saving render time by scrapping reflections - "...you can get back a lot of render time by eliminating the (blurred) reflection...", so I did that.

The ivy I'm using had no bump, so I generated a simple bump map in the shader from the original leaf texture. I also used a clouds node to provide some (hardly noticeable!) colour variation amongst the leaves.

Here's the shader network:

And here's part of the resulting render - Poser 9 Firefly render, auto settings halfway between draft and final with IDL quality increased to 20, IDL (my own worldball with LDR JPG) + an infinite (40degree elevation above the camera):

My guess is that the scatter node isn't doing much (as per bagginsbill's already noted comment) - so the only effect I'm really seeing is the from the specular (Blinn) and bump?

In a totally different thread on IDL and single faced architecture bagginsbill noted that scatter is the 3D version of translucence.

Now, since scatter won't work on many plant leave meshes (including most XFrog OBJs) as they have no thickness, I'm thinking that plain old translucence might be worth a shot? But I don't see any nodes that would perform this function and replace the scatter node. So that leaves the Poser surface translucence. But here's the rub - it always seems to work just like ambient when I use it!

I think the main question I have is this:

Since the scatter node isn't designed to work with one-sided zero-thickness objects, is there a way we can modify the leaf shader to have a translucent/scatter part that will work with all those old plant models that we all have with one-sided zero-thickness leaves?

I was beginning to think that the fastscatter node might be the answer (e.g. from 2008 "...Fastscatter handles backlight SSS...") until I found 2005's   "...only to discover that Point Lights cannot have Depth Mapped Shadows (which FastScatter requires)..." , and then this 2012 comment from bagginsbill: "...FastScatter and the Translucence channel are pretty much self-lit. Get rid of that..." So maybe translucence/fastscatter are non-starters?

I mentioned in the previous post that I guessed that the scatter node wasn't actually doing much. So just to check that I tried the old-fashioned very simple diffuse/specular/bump (no alternate). Here's the result (and yes, I forget to apply the transparency mask to specular strength, hence the ghostly white squares):

I think that more-or-less confirms what I thought? Here's the very, very basic shader I used (render settings were exactly the same as before):

Obviously my observations are limited to this specific scene/viewpoint with its specific lighting setup.

Going back to bagginsbill's comment that "... Since they have no thickness, scatter doesn't really do its job, which is a big part of the realism of a leaf shader...", I'm intrigued by the "...doesn't really do it's job..." part.

• So for one-sided zero-thickness leaves does the scatter node do enough to be worth using?

• Are there certain situations where we will see a difference (e.g. backlit leaves shadowing each other)?

Quick experiment. Four leaves, two are one-sided flat zero thickness, two are solid volumes (basically just the flat ones extruded, with all normals facing out). bagginsbill's scatter node leaf shader without the reflect part, using a texture image and derived bump.

Worldball for IDL, and one infinite light with raytraced shadows. Poser 9 render as per the two posts above.

Lit from in front by the infinite:

And backlit:

Definite nice translucence effect on the backlit solid-volume leaves.

(Can't tell whether that's translucence on the flat leaves - done a couple more checks - it isn't, just the leaf colouration)

(Worth noting - I'm looking at the front of the one-sided leaves for the backlit image, i.e. I can see the leaves in preview mode. For the front lit view the flat leaves don't show in preview mode)

On a whim I lit the one-sided leaves from the front and moved the camera round the back of them, so I'm looking at the back of the leaves (i.e. can't see them in preview) and they're backlit...

Shader network:

Due to a nearly complete lack of documentation for the material system, much of what I know is from hypothesizing how something works and then testing the hypothesis. However, this somewhat failed me in determining what the Translucence channel does, or more specifically how it was intended to be used. Largely it does act like the ambient or alt_diffuse in that it just seems to emit whatever you set it to or plug into it. But that's not its purpose. Unlike those others, this channel reverses the normals used in Diffuse lighting calculations of a dedicated Diffuse node. It is so that you can get the back-lit paper-thin effect from either side. It is only useful for one-sided objects like your leaf. It does not help in any way with solid objects if shadows are enabled as they should be. In order to get it to do its back-lit paper-thin effect, you must plug in a Diffuse node, with the Normals_Forward option checked, and you must not send the data from that diffuse node to any of the other channels in any way. It must be dedicated to the Translucence channel.

I must add that it is buggy as hell. As far as I can see it is doing its thing as designed for directional lights and a dedicated Diffuse node, but for IBL or IDL, it doesn't behave like real translucence under those lighting conditions. I still advise not to use it, unless you first study it completely and understand how it will burn you if you go where it cannot go.

Here's a demonstration. I'm using this basic diffuse-only shader for a leaf to keep things simple.

My scene has a leaf and two pawns. The pawn behind the leaf is upside down. We are looking at the "front" of the leaf.

Ambient lighting is a small amount of IBL (could also be an envsphere) and I have IDL enabled. I also have an infinite light shining on the front of the leaf, from behind the camera. Its shadow is very evident.

Viewed from behind, everything is as we expect.

Now the main light is behind and we're looking at the front. This is the back-lit paper-thin effect, provided by our Translucence channel.

Here I turned off Translucence_Value (0) and now we see what it was doing.

None of the back-light is getting through at all - we're only seeing the ambient lighting from the IBL+IDL.

Still with no Translucence enabled, looking once more from behind, with front lighting, we see translucence. !!? Why is that?

The Translucence channel has only one job - to convey BACK lighting to the front. It is not responsible for conveying FRONT lighting to the back. As we can see this is already performed by the completely ordinary lighting of the built-in diffuse node (or any diffuse node).

What does this mean? It means that, for example, if you're looking up into a tree with the sun shining down, and the "front" of the leaves face up, you're looking at front-lit back-viewed paper-thin, and that is NOT the job of translucence. That will work no matter what.

You ONLY need translucence when you are BACK-lit front-viewed paper-thin. Change any of those three factors and it will not help you at all.

One more point to make - this is about the modern ambient lighting from IDL.

I introduced a glowing prop. Here we are back-lit, back-viewed, with a glowing prop light source. We can clearly see the nice soft shadow from the IDL being blocked by the back pawn.

Now we switch to front view. This is back-lit front-viewed paper-thin - we expect translucence to work here. But it does not.

In case you were wondering, front-lit back-viewed IDL doesn't do a shadow either.