Hi all, Two questions this time for y'all :rolleyes: 1: Is it possible to create for example, a gradient color shift to hair that uses an image as a texture ? I know how to do it via Photoshop but i would like to know if it can be done in the Poser Material Room. 2: Also, can i change a hair color (or a cloth color for that matter) directly in Poser that also uses an image for its texture ? I guess this would be a 'node' thingy :sneaky: Thanks Wim

Changing color uniformly is pretty easy:
http://www.renderosity.com/mod/forumpro/showthread.php?message_id=2927631&ebot_calc_page#message_2927631

Changing color across a gradient is a little harder, I don't have an example at my fingertips, but might be able to throw something together in a few minutes.

You can use the Color_Ramp node for the gradient, with the U or V variable node to drive it.  In fact, you can drive the Color_Ramp node with a lot of different things to get some completely barking mad effects. :)

Hey thanks pjz99, i read the thread you gave and indeed, changing colors is fairly easy ! SamTherapy, could you maybe show me some screenshots please :blushing: then i would understand it a bit better i think.

Quote - Hey thanks pjz99, i read the thread you gave and indeed, changing colors is fairly easy ! SamTherapy, could you maybe show me some screenshots please :blushing: then i would understand it a bit better i think.

Give me a few minutes and I'll post something up.

I'm waiting for an example to render at the moment but I can tell you right now that it looks absolute bobbins.  The idea will work effectively if the hair you're using has one flat texture layout.  Otherwise, you're going to have to play around masking bits out, changing parameters here and there.  Probably easier to make or adapt an existing texture map.

I'll post the pics in a while, just for the sake of reference.

Ooh thanks Sam ! Oh what fun it is in the Material Room now that i learn how to change things Off to play with it now :tt2: Sam, is there any way to edit the gradient (change the direction of it) for example, let it change from left to right or maybe from the center to the edges ? Or is it only from top to bottom as it is on your screenshot ?

Yes, you use the u_Texture_Coordinate for a left to right gradient.  You can also connect other math nodes and variables in there to give radial gradients or lava lamp effects.

A good source of ideas and useful stuff in its own right is a pack of free shaders posted by Ajax, which you should be able to find in Freestuff.

Yes

r = sqrt(x * x + y * y)

We can get circular gradients.

For x we use 2U - 1.
For y we use 2V - 1.

The Sqrt node shows the circular gradient. We then plug that into Blender or ColorRamp. Again, we can use Bias to accelerate or retard the gradient in r.

 Here I've used 3 * x * x + y * y. This gives us an ellipse instead of a circle.

Here I've raised them to the 4th power instead. The gradient becomes more square.

Fascinating, eh?!?

Nice one, BB!

Great visual examples, thank you so much

Wow BB, thanks alot for all the examples ! This is gonna keep me busy next weekend, i would never have guessed that there was so much control power in the Material Room :-) Thanks all for showing me how to do this Wim

Glad you like it. It's actually quite incredible what you can make with these nodes and the U/V coordinates.

For example, the pattern of fish scales in my avatar is done entirely with nodes - no image map was used.

Here's the full size image:

Or check out these bricks - all nodes:

Making patterns out of pure math on U and V is kind of my specialty. Check out this Glenn Plaid cloth pattern - all nodes - no images.

Any chance the nodes can make velour material for a sweatsuit? In POSER 6?

Quote - Any chance the nodes can make velour material for a sweatsuit? In POSER 6?

I've tried a couple times without doing better than others have. There are some free velvet materials here and also at RDNA that are ok.

Velour and velvet shaders that others have done are similar to real velour in the same way that a box is more similar to an SUV than a sphere - directionally correct, but lacking accurate details. Most of the shaders I've seen end up looking more like satin, or more like terry cloth. I don't fully understand the physics of velour well enough to produce great results yet. I spent 3 hours on it this morning and failed.

I've attached the Poser material file - save it as Velvet.mt5, removing the .txt at the end. I had to add that to be able to upload to this forum.

To change the colors, go into the material and find the Simple_Color node. Put any color you want in there.

I'll show the render next.

That really looks great Bill.  Could you do me a favor (probably others as well) and also post the material file for the stuff you're doing with gradients above?  I was trying to reproduce it and didn't quite get it, I'm interested to take a close look at how you did it without my fat-fingering it and introducing some wrong config.

Heheh. You think I saved those? I typed them in - took screen shots - and deleted them.

There's nothing difficult about making them from the screen shots. Anything that looks white is white. The numbers are all easy to read, I think. Each example builds on the previous so you don't actually have that much to type in. 

Give it a shot.

Quote - Well well. I started over, discarding the Velvet node and the bump map. Working from scratch using Edge_Blends and Blenders, this is what I came up with.

I've attached the Poser material file - save it as Velvet.mt5, removing the .txt at the end. I had to add that to be able to upload to this forum.

To change the colors, go into the material and find the Simple_Color node. Put any color you want in there.

I'll show the render next.

I LOVE YOU!!!!!

I'm going to apply this material to some sweats I have and post them. :)

Thanks!

CLICK TO ENLARGE

bagginsbill is the velvet node bad or was it because we didnt gave gamma correction?

I don't know if the velvet node is bad or not. Like so many other nodes, I cannot find the formula - what it actually is doing. Since I know what I want to do, but I don't know what it is doing, I don't use it. Given the choice, I do what I want mathematically, not guessing. I have done much experimenting with nodes, but any that are specialized with no explanation are essentially useless to me. I'm not going to work out the millions of parameter values and how they influence each other if I can build what I want in 20 minutes from math nodes.

thanks.
i tryed the one that you posted here in 2007.looks very good. but its not GC. how would you transform this to GC?

I just did this in Poser Pro, so the version number is high. People without Pro will get  warning - ignore that, or you can fix it by editing the material file in a text editor - change the version to 5.

Thanks so much bb! I just loaded it up into my Poser. Okay, so I have a question. I try to follow the threads, but  I guess I have missed where this was discussed. If I were to add GC to a hair texture, where would I begin attaching nodes for the hair textures into the GC nodes?

Here is a screen shot of a decent GC shader for most things.

http://www.renderosity.com/mod/forumpro/media/folder_9/file_423332.jpg

This shader implements the correct way to do GC and also to trade off specular versus diffuse reflections. Other than that, it's your basic diffuse and specular effect.

It uses a Blinn node for specular, which is much more realistic for most things than a Specular node is. The Specular node is what is built into the Poser Surface - what most people have used. You can use the Specular node instead of the Blinn node if you like, to make an existing hsader more like what it already is.

If a shader has some other specular node, such as Glossy or Anisotropic, it would probably be plugged into Alternate_Specular. Unplug it from there and put it where this Blinn goes.

If you have transparency, bump, or displacement there's no need to change those parts. GC only deals with the generated colors.

In that shader, I showed a color map from a texture set. This is the color of the material. It does not have to be a map. Instead, you could plug in nodes to make the colors, so if you're converting a procedural texture, that's where you'd plug in the colors. Most shaders, even procedural, have the important color generating nodes going into Diffuse_Color. Whatever they are, just plug them in where you see the color map.

If you're converting a shader that uses ambient or translucence, it's probably a bad hacked-up I-don't-know-why-I-did-that-I-just-thought-it-looked-good type of shader and you should not convert it. :)

Thank you! I'm copying and pasting into a Word document for my Node files.

What are your thoughts on using material based AO on a hair texture? I've plugged in AO to a hair texture a few times. Sometimes it looked good on final render, sometimes it seemed to only make for a longer render.

Quote - Here is a screen shot of a decent GC shader for most things.

http://www.renderosity.com/mod/forumpro/media/folder_9/file_423332.jpg

This shader implements the correct way to do GC and also to trade off specular versus diffuse reflections. Other than that, it's your basic diffuse and specular effect.

It uses a Blinn node for specular, which is much more realistic for most things than a Specular node is. The Specular node is what is built into the Poser Surface - what most people have used. You can use the Specular node instead of the Blinn node if you like, to make an existing hsader more like what it already is.

If a shader has some other specular node, such as Glossy or Anisotropic, it would probably be plugged into Alternate_Specular. Unplug it from there and put it where this Blinn goes.

If you have transparency, bump, or displacement there's no need to change those parts. GC only deals with the generated colors.

 

why is the specular subtracted and plugged in the diffuse? 

For conservation of energy. Because it looks better.

Let's say using some incredible physics monitoring equipment you watch 1000 photos arrive at a surface.

Let's say 300 of them (30%) bounce of the air-surface boundary, making a specular reflection. How many are left to make a diffuse reflection or sub-surface scattering? Not 1000 any more, but 700. The other 300 left already.

So - where there is more specular there must be less diffuse. QED.

There is also the hyper-color problem.

Consider a bright red plastic, RGB(255, 0, 0). Diffuse reflection from a 100% light would produce RGB(255, 0, 0). But what if you are looking at a spot that produces a specular reflection of RGB(50, 50, 50)? Then the sum is RGB(305, 50, 50) which is impossible to render. What happens is the red gets clipped so the actual rendered color is RGB(255, 50, 50).

Now what happens as you look at the surface falling away from the hot spot? The diffuse and specular are decreasing with the changing angle. But! Because of the hyper-color clipping, the red component is still 255, while the blue and green are dropping 40, 30, 20, etc. This looks strange, and produced a glowing halo around the hot spot.

I will render a demonstration. Give me a few minutes.

interesting. but where could we now connect the AO?

Notice the yellow ring around the highlight on the left?

To connect AO, add a Math:Mul node. Connect it to Diffuse_Value. Connect AO and the 1 - specular to the Mul node.