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Thomas M.
10-23-2006, 06:08 PM
If it's not me to blame, then I'll torch someone pretty soon. At least I'll consider it. 3 1/2 month of begging for bug fixes.

I do have a glass object (simple box object, 5mm thick) and an object beneath it. The lights pitch angle is 90° (distant light), so it is shining exactly from top of the scene. If I turn on 100% transparency and IOR 1.54 it looks o.k., double sided enabled. The object beneath it is bright and receives the rays from the lightsource.

If I choose nodes instead of the classic texturing menu, the object remains black, never mind what kind of setup I use in nodes. Refraction node in diffuse shading like always: No light passing my glass object so the object beneath lies in total shadow. If I disable "cast shadow" for the glass it works, but as glass has a density to it, it cast a shadow. Worked for years, but now the nodes f... it up.

Reflections on the object beneath the glass show up, so the glass works for the diffuse and specular light like a sunblocker. Not very nice, at least not for 100% transparent glass.

Can anybody confirm this bug? If yes, I start to collect some wood for a nice fire. Unless I'll get this s... fixed in the next few days.

Cheers
Thomas

SplineGod
10-23-2006, 06:39 PM
Are you using air polys ?
If not you can use the Spot info node and logic nodes to give the other side of your polys a different IOR.

Celshader
10-23-2006, 07:43 PM
If it's not me to blame, then I'll torch someone pretty soon. At least I'll consider it. 3 1/2 month of begging for bug fixes.

I do have a glass object (simple box object, 5mm thick) and an object beneath it. The lights pitch angle is 90° (distant light), so it is shining exactly from top of the scene. If I turn on 100% transparency and IOR 1.54 it looks o.k., double sided enabled. The object beneath it is bright and receives the rays from the lightsource.

If I choose nodes instead of the classic texturing menu, the object remains black, never mind what kind of setup I use in nodes. Refraction node in diffuse shading like always: No light passing my glass object so the object beneath lies in total shadow. If I disable "cast shadow" for the glass it works, but as glass has a density to it, it cast a shadow. Worked for years, but now the nodes f... it up.

Reflections on the object beneath the glass show up, so the glass works for the diffuse and specular light like a sunblocker. Not very nice, at least not for 100% transparent glass.

Can anybody confirm this bug? If yes, I start to collect some wood for a nice fire. Unless I'll get this s... fixed in the next few days.

Cheers
Thomas

I have a few questions...

What is your Ray Recursion Limit value? If it's set too low, the ray will return the value of the backdrop (which is black by default).

Also, can you post screengrabs of the Nodes that you are using and examples of both the "good" and "bad" renders?

Thomas M.
10-24-2006, 01:35 AM
I'll post the scene a.s.a.p.

Ray rec is at 12, all raytracing options enabled, air polys via logic nodes and spot info. Objects are part of the same object, but on different layers.

As I said, if I disable "cast shadows" the object is bright. Enable this option and there is total darkness. Only reflection or luminosity is shining through the glass.

Thanks so far.

Thomas M.
10-24-2006, 03:28 AM
O.k., here's the scene.

Please place a HDRI or other image in the background, so that you can judge the transparency of the material. Switching the "Cast shadow" button for object layer 1 (Glass) shows the difference. As the material is pretty much transparent at the viewing angle, the light falloff should only be minimal. Unfortunately it's devastating. Turning up diffuse for layer 2 doesn't make a difference (1000% and above). No light passing through.

Unchecking the node button for glass and setting transparency up to 100% and IOR to 1.54 (or whatever) brings us back on track.

If this isn't a bug I'll eat my shorts.

Cheers
Thomas

P.S.: Thanks for any feedback.

Dave Jerrard
10-24-2006, 03:53 AM
If I choose nodes instead of the classic texturing menu, the object remains black, never mind what kind of setup I use in nodes. Refraction node in diffuse shading like always:My guess is this is the problem. The refraction node should be connected to the Refraction Shading input, NOT the Diffuse Shading. No nodes connected to the Diffuse Shading input will affect the surface's transparency. Even though it might look transparent, it's not, and you'll get solid shadows. The refraction you see on the surface is actually treated as a texture map in this case.

The Refractions Node really should be plugged into the Refraction Shading input, which is controlled by the Tranparency channel. The Refraction Shading channel - or buffer - tells the surface what to refract. But it still needs to be told how much of this refraction is visible. It gets this info from the Transparency channel. If you leave Transparency set to 0, then the surface is not transparent. And a non-transparent surface will not refract any light going through because no light can go through it.


No light passing my glass object so the object beneath lies in total shadow. If I disable "cast shadow" for the glass it works, but as glass has a density to it, it cast a shadow. Worked for years, but now the nodes f... it up.No they don't. They're doing their job. You just haven't told the surface it's transparent, so it's going to block all the light rather than transmit it.


Reflections on the object beneath the glass show up, so the glass works for the diffuse and specular light like a sunblocker. Not very nice, at least not for 100% transparent glass.Reflections work because they're reflecting what they see on the inside surface of the glass. Remember, the Refractions node is essentially painting a refraction solution onto the glass object, not actually making it transparent. The specularity is blocked because that needs a direct line of sight to a light. Since you have a surface that's not actually transparent between the object and the light, the object is in shadow, so no light and no specular highlights.

He Who Will Have Some Examples In A Bit.

Thomas M.
10-24-2006, 05:30 AM
That sounds interesting, but so far I never had any luck in using the Refraction Shading or Reflection Shading. All stays black. And so far I've never seen in any thread or any video or any tutorial (never mind the "manual") an example of how this stuff works.

As far as I can tell, for LWers this is unknown territory.

Any ideas?

Cheers
Thomas

P.S.: By the way. If you are right, it fücks up my whole node understanding.

Dave Jerrard
10-24-2006, 05:37 AM
Here's some examples. In this one, I have a Refraction Node plugged into the Diffuse Shading, using a Logic node to set the air surface, and a gradient to define some incidence angle reflectivity. There's a reflective orange box inside this ball, and the ball has an IOR of 2. There is no transparency.

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As you can see, the shadow of the ball is solid black, and you also can't see any light hitting the box inside the ball. The box is still reflective, but that's because it's reflecting what visible on the inside of the ball, which is the Refraction Node's output. Now, for a crystal ball like this, a dark shadow is actually pretty accurate, as this kinda simulate the caustics that would normally happen. But if you were to apply caustics to the scene, the ball would not cast any, again, because it actually has no transparency.

Now in this image, I've connected an incidence angle gradient to the Transparency channel. Now the shadow is very transparent and you can see the light affecting the box, showing the orange color.

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But the Transparency value is not affecting the amount of refraction seen in either image. This is because the Refractions Node is plugged into the Diffuse Shading, rather than where it should be - the Refraction Shading input.

Here I just moved the Refractions Node's connection from the Diffuse Shading to the Refraction Shading input. Nothing else has changed.

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About the only visible difference is the darker edge on the ball - it's more accurate now - and the color change, due to the color of the ball being magenta and the Diffuse level being set to 100%. Previously, the brightness was being incorrectly boosted because the refraction was being treated as diffuse shading. The ball's color was also being overridden by the refraction colors being fed into the Diffuse Shading, which actually overrides the Color, Diffuse and Luminosity channels.

In this last image, I removed the gradient from the Transparency channel again. Notice that there's no longer any visible refraction. The ball appears to be an opaque, magenta ball - which it is now.

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He Who Thinks He Has More Examples Coming Up.

Dave Jerrard
10-24-2006, 06:06 AM
That sounds interesting, but so far I never had any luck in using the Refraction Shading or Reflection Shading. All stays black. And so far I've never seen in any thread or any video or any tutorial (never mind the "manual") an example of how this stuff works.The bsics for using the four shading inputs at the bottom are...

Diffuse, Translucency and Subsurface Scattering nodes plug into the Diffuse Shading input,
Specular nodes go to the Specular Shading input,
Reflections nodes go to Reflection Shading and,
Refraction nodes go to Refraction Shading.

Now you can mix them up if you want, since you can get interesting effects, like a transparent object with a solid shadow... But generally, follow the list above.

The Occlusion node is a special case and isn't tied to any shading input - it's more of a control for other nodes. But it can be fed into these if all you want is an occlusion buffer.

Since you're saying that everything stays black, my guess is you'r enot setting anything in the Reflection or Transparency channels, either in the Surface Editor or in the Node Editor. It should be noted that the Reflections nodes work in a similar fashion to the Refraction Nodes. The Reflection Shading input is controlled by the Reflection channel. All the Reflection Shading does is define what the reflections look like. The Reflection Channel defines how much of the Reflection Shading we see.

So to recap, Transparency controls how much of the Refraction Shading is visible and Reflection controls the amount of the Reflection Shading that is visible.

Diffuse Shading overrides the Color, Diffuse and Luminosity channels since these are all aspects of the internal shading model in Lightwave, which is the Lambert shading model. To use a different shading model, like Oren-Nayar or Minnaert, you need to feed the color and diffuse values into that shader, which is then fed into the Diffuse Shading. Feeding a color directly into Diffuse Shading makes the surface that color, regardless of lighting, essentially making it a luminous surface

Specular Shading also overrides the Specularity and Glossiness channels. Each Specular node has its own controls for these.



P.S.: By the way. If you are right, it fücks up my whole node understanding.Only with the shading inputs. You can do nodal surfacing using the all the other inputs just like you did before with the Surface Editor and texture layers - these work the same way. It's the four red dots at the bottom that require special handling, and that's because they add some greater texturing power. They actually get in and override the internal shading system that LightWave uses, much like shader plugins like BRDF, Natural Shaders or G2 do. The shaders tend to group multiple aspects of a surface together, or even use new settings (like Minnaert's Darkening value, or Anisotropic's U and V amounts). You don't need to use them if you don't want to. You can do glass the old way, or you can use the node versions of those same channels, or you can use the shading inputs. The nice things about Nodes is that you can mix & match most things quite freely.

He Who Usually Uses The Transparency And Reflections Channels In The Surface Editor With Nodes.

Thomas M.
10-24-2006, 08:38 AM
Dave, that's some great stuff. Thanks for all the explanations and the examples.

May I just ask you for one favour. If you look at my glass surface, you probably see how I used to deal with nodes and I guess my way is great, except from that it doesn't work correctly. Wished though.

Can you translate my approach to your understanding of how it works and post the node? Probably that would help me to get the written word settle in my brain.

Thanks very much anyway.

Cheers
Thomas

Thomas M.
10-24-2006, 11:14 AM
I guess I'm not getting it yet. Played around a bit, but I'm still confused.

Diffuse Shading and Specular Shading work great so far. I don't need any setting in Diffuse nor Specular to get everything done. This way I can mix shaders and everything nicely.

Now you are telling me that in order to make Reflection Shading and Refraction Shading work, I need to have settings in Transparency and Reflection. If it is so, how can I achieve multi-layered reflection materials with diffuse and refraction properties? So far I thought it's either Standard texturing, Nodal texturing with green input dots or Nodal with red dots.

What would I need two inputs for reflection for? I guess your logic is pretty o.k., but I don't see the general idea yet. So far (using my logic, wrong one?) I could mix many reflection layers with diffuse layers. Using your system I wouldn't know how to do so.

Probably you can post a node tree from your set up (perfect glass).

Also I'd love if a NT guy could jump in, as the manual and other documentation lack any information of how to deal with this stuff. Also in all the forums nobody as far as I believe really understood how to work with the Reflection and Refraction Shading.

Don't let Nodal become another mistery like IKBooster. A video or tutorial would be more than welcome and needed.

Cheers
Thomas

Thomas M.
10-24-2006, 11:18 AM
P.S.: My nodal tree approach looks much more convenient than the one described by Dave. What's the advantage of all four Shading inputs?

Dave Jerrard
10-24-2006, 03:42 PM
Dave, that's some great stuff. Thanks for all the explanations and the examples.

May I just ask you for one favour. If you look at my glass surface, you probably see how I used to deal with nodes and I guess my way is great, except from that it doesn't work correctly. Wished though.

Can you translate my approach to your understanding of how it works and post the node? Probably that would help me to get the written word settle in my brain.

Thanks very much anyway.

Cheers
Thomas
I didn't even notice the file you posted earlier. I just grabbed it and I'll take a look.


He Who Only Got Into Nodes Because Of The Shaders.

bryphi7
10-24-2006, 03:52 PM
if you use the reflection shading, you still have to set a scaler in the original reflection input...If you didn't know that already?

Dave Jerrard
10-24-2006, 05:52 PM
Ok, let's pick that node map apart...

The first thing I see that's not right is you have a logic node applied to the Transparency channel, setting different transparency values for front and back faces.
38195
With this setting, True means the front face of the polygons and false is the back side. This tells the front faces to be 0% transparent. There's no transparency, so this makes the second logic node, which controls the Refraction Index, less than useful...
38196
A non-transparent surface can't refract light. And since you can't see into the surface, you'll never see the inner air surface (or backsides of polygons), unless those are facing outside of the objects.


Next you have a Refraction Node and a Reflection Node going into a mixer, which is then plugged into the Diffuse Shading. These should't be mixing - they should go into their respective shading inputs. I'm not sure what the Air-to-glass gradient is really doing, but it's not what you think. If you want to have the mixer switch between FG & BG based on which side of the polygon you're looking at, then the easiest way is to just feed the Polygon Side info to the Opacity input on the Mixer, leaving the Blending Mode set to Normal. Polygon Side outputs either a 0 (backside) or a 1 (frontside), and this value, when fed into any green dots is treated as a percentage, where 1 = 100%. So, this gives the Mixer's Opacity input either a 0% or a 100% value. In the image below is your original settings (and my backdrop since your HDR Image wasn't included) on the left and my result of just replacing the gradient with the Polygon Side info.

38197

Now since you mixed two different types of shader here, the results are going to be wrong - Reflection should go to reflection and refraction to refraction. So let's fix this up a bit. Here's a couple versions that do the same thing. The first is a larger, more complex one, based on the nodes you had setup already. They're just reorganized a bit here.

38198

This second one does the same thing, but doesn' tuse as any nodes. Two shaders were removed because they weren't doing anything that wasn't already handled identically in the regular surface channels.

38199

Both of these render the exact same image. Since I've used up all my attachment slots, I'll post the object in another message so you can take a closer look at the nodes.

He Who Didn't Think He'd Be Using Nodes Much, Until He Saw Those Shaders.

Dave Jerrard
10-24-2006, 05:57 PM
As promised, here's the files. Also, here's a render of what the adjust node graphs do now.

He Who Forgot What He Was Going To Do Next.

serge
10-25-2006, 01:53 AM
Dave,
Very clear and logical explanations. Thank you. Useful to many people here I believe.


...He Who Forgot What He Was Going To Do Next.
Working on a Node-manual and tutorials maybe? :)

Thomas M.
10-25-2006, 04:15 AM
Very nice explanation. Though you took all the beauty away from what I felt for the nodal approach.

My gradient (glass-air) isn't in any way related to the poly side. It's just a nice way to simulate the fresnel effect as it blends the reflection and refraction according to the incidence angle. I set the transparency of the front poly to 0 as I thought my refraction node would take care of this. This works nice, as long as your main objects isn't transparent, but only it's upper surface, e.g. wet watery film ontop of skin.

Your approach looks correct (but complicated - to me), but it's more or less the old surfacing way. For instance I wouldn't have a clue of how to deal with two or three different layers of a car lacquer with each layer having a reflective, refractive and diffuse and specular amount going your way, as you seperate everything. If you split up each of these attributes, how can you simulate the order of these layers or even combine them in a way that you can feel what each layer does? My way has been efficient concerning these materials.

Example: Bottom layer with a diffuse paint, middle layer with metallic reflecting particles and diffusion and a shiny top layer with reflection, refraction and little diffuse amount.

Probably I just have to get used to the way you see nodal, as you just shattered my view of the world.

The only point that remains is that I have to ask myself, why all these inputs. It would be much more convenient to have only one input in the Base node and you can mix up all reflection, specular and other nodes in one tree. What's the advantage of seperating the 4 major shading models (refl, refr, spec and dif)?

Thanks you very much for the time spent to help me out.
Thomas

Thomas M.
10-25-2006, 04:21 AM
P.S.: Wouldn't it be better to set reflection and refraction to 100% and control the amount of both of them by the amount of the reflection or refration node (e.g. with mixer and gradient)?

Tesselator
10-26-2006, 11:07 PM
P.S.: Wouldn't it be better to set reflection and refraction to 100% and control the amount of both of them by the amount of the reflection or refration node (e.g. with mixer and gradient)?


When using node based reflections and refractions there is a separation of
aspects you have to cconsider. One aspect being the Amount of refraction
or reflection and the other being the properties of the materials that are
refractive or reflective (e.g. diamonds refract and reflect differently than
clear plastic). This later aspect we'll call shading. So we have "Shading"
and "Amount" for both reflection and refraction.

Refraction and reflection shading is controlled by any nodes that are hooked
up to those inputs in the surface destination node - "Refraction Shading" and
"Reflection Shading" respectivly. It is advisable to use the shading nodes
from those respective "Add Node" categories but you don't have to. This
"Shading" thing for these surface attributes is a new thing for LW.

"Amount" is controlled by all of the usual mechanisms [T], [E], or Numeric
constant values as entered into Surface Editor. It is also possible to set
these Amounts via node networks that are connected to the green dots
in the "Surface" destination node, labeled "Transparency" or "Reflection".
These are the same controls we've always had even if now there is a new
way to define them via node networks.



I wouldn't have a clue of how to deal with two or three different layers of a car lacquer with each layer having a reflective, refractive and diffuse and specular amount going your way, as you seperate everything. If you split up each of these attributes, how can you simulate the order of these layers or even combine them in a way that you can feel what each layer does?


There probably wouldn't be any refraction in car paint ;) but this kind
of multi-aspect surface would be achieved in nodes by using Mixers.
Additionally you could also use a different normal textues (bumps) for
each "layer" thus enhancing the effect of difference and depth.

Thomas M.
10-27-2006, 04:25 AM
THanks for the additional answers.

The point is, with non-transparent surface I don't have any problems to use very complicated nodal trees with loads of mixed settings.

The thing which bothers me is that I don't need any of the green inputs in the base node while working with diffuse shaders. They control both shading and amount of brightness, so there's no need for green diffuse or color settings . Everything works great with Diffusion shading.

Same for Specular Shading. No need for the green inputs. All can be done with my Specular shaders (incidence, amount, colour, mixes, ...) in the Specular Shading slot.

So, if it comes to Reflection and Refraction Shading, following your and Dave's explanations, the red input Shading slots merely tell LW what shading model is used, but the amount needs to be regulated with an "old" green input node? That's pretty much confusing me.

bryphi7
10-27-2006, 04:32 AM
close...With reflection you still need to use the regular scalar input, refraction you do not...You can set refration in the refracton shading node.

Thomas M.
10-27-2006, 06:33 AM
Doesn't make any sense in my opinion. One input in the base node would be much more convenient than splitting the four of them up like this. No advantage as far as I can see, only disadvantages.

Dave Jerrard
10-27-2006, 12:26 PM
The point is, with non-transparent surface I don't have any problems to use very complicated nodal trees with loads of mixed settings.When you get into more complex node maps, you will start to run into a lot of problems if you're not aware of how those shader inputs work, as you've already discovered with the transparency issue.


The thing which bothers me is that I don't need any of the green inputs in the base node while working with diffuse shaders. They control both shading and amount of brightness, so there's no need for green diffuse or color settings . Everything works great with Diffusion shading.The Diffuse Shading overrides the red Color input and the green Diffuse and Luminosity inputs, and those corresponding channels in the Surface Editor. (It also overrise the Diffuse Sharpness control.)

Anything in those channels is ignored when Diffuse Shading is used. The reason is those three channels actually define the settings for the internal Lambert shader that LightWave uses. If you look at the Lambert node, you'll see that it has the same Color and Diffuse settings, and that if you plug the same textures into these and into the Surface Node's Color & Diffuse channels, you'll get the exact same result. What nodes offer here that you can't get otherwise is that you can have multiple shaders blending together, so you can have multiple specular highlights, each with its own color, like you can with BRDF or Gaffer, but with far more control. In fact, you can texture each one differently, even adding bumps to one highlight while the rest remain smooth - which makes for a really effective car paint.

The Luminosity setting is missing from the Shader Nodes for a reason. A diffuse shader controls how light is reflected off a surface - what falloff it has at various angles, etc.. Luminosity doesn't care about the lighting at all. Luminosity is actually a sort of shading override - the higher the value, the more the shader is overridden. If you take a surface and make it 100% Luminous and 0% Diffuse, it will look flat. It will also look exactly the same if you it 0% Luminous, 100% Diffuse with 100% Ambient light only.


Same for Specular Shading. No need for the green inputs. All can be done with my Specular shaders (incidence, amount, colour, mixes, ...) in the Specular Shading slot.You're kinda right here... When you're using the Specular Shading, it overrides the Specularity and Glossiness channels (and Color Highlights), so no, it doesn't need them. Those are just the settings for the internal Phong shader, and you'll find the same settings in the Specular Phong node, but with one important addition - Color. Without the nodes, your specular color is limited to the light color, or, if you use Colored Highlights, whatever the surface color is, or its negative (if you have a negative Specularity), unless you use another shader plugin (Gaffer, BRDF, G2, etc.). If you want to do something like a pearl, where the surface is white but the highlights are many irridescent colors, you now need to set up a second surface slightly raised above the white surface, just to get those colors (100% transparent, multi-colored, with Colored Highlights turned on).


So, if it comes to Reflection and Refraction Shading, following your and Dave's explanations, the red input Shading slots merely tell LW what shading model is used, but the amount needs to be regulated with an "old" green input node? That's pretty much confusing me.You don't sound confused because you just nailed it. That's exactly what those inputs do - let you define what shading - if any - is being used. You don't need to use these at all, because LightWave has built in shaders that all the old channels have been using for 16 years or so. So you can do most of your surfacing without ever touching these four shading input - just use the inputs above them. But, when you want to change a shading model, like to get a more realistic rock or velvet shading (use Minnaert or Oren-Nayar), or a better brushed metal (Anistropic shaders), or Subsurface effects (Kappa, Omega), then you plug those nodes into the appropriate shading inputs, and instead of feeding all the textures these look for into the Surface Node, you feed them into the shader.

Here's a tip. The red dots are color inputs. They only deal with three values - red, green and blue. So, those shading inputs essentially only concern themselves with a color, and they don't really care where that color comes from, be it a shader node, procedural texture, image, whatever. In the case of Diffuse Shading, this is the color of the surface. If you plug in a texture directly into this input, then that's the color the surface will have. Unless that texture also does some kind of shading, the surface will not be shaded at all - lights will not affect how bright or dark it is. Since no shader is applied and this input overrides the internal one, the colors that are fed into this input will not change - you'll get exactly what you put into it. Remember what I said about Luminosity being a shader override near the beginning of this post? The surface will be luminous (yes, it will even cast light if you use radiosity). Now, with a mixer and a diffuse shader, you can have a surface with a luminosity that's a different color than the diffuse color, without having to put that luminous color into the difuse color first. Once these are mixed with a mixer node, the final color is output to the Diffuse Shading

Specularity works in a similar way, but the Specular Shading input is added to the Diffuse Shading's color. You could do this yourself, using a mixer or math node to combine it with diffuse shaders, and pump it all into the Diffuse Shading to get the same result, but then you'd lose the ability to utilize the Specularity buffer. It's also usually neater to avoid this kind of mixing.

Again, if you really want to, you can feed any output into this input, but in most cases, this wouldn't make any sense. Whatever is being fed into this - a solid color, texture, gradient, etc. - will have its output added to the diffuse shading.

Reflection and Refraction are also color inputs. These are each blended (each in their own way) with the diffuse shading based on the amounts defined in the Transparency and Reflection channels. These also override certain other channels... The Refraction Shading overrides the settings in Refraction Index (if a refraction node is used), Color Filter, Additive Transparency, Refraction Options (Environment tab), Refraction Map, Image Seam Angle and Refraction Blurring.

Reflection Shading similarly overrides the Color Highlights, Reflection Options, Reflection Map, Image Seam Angle and Reflection Blurring settings.

Again, you can pretty much feed anything into these since they're only color buffers, but it makes most sense to use the appropriate shader nodes. For example, here's the same ball rendered three times. I've plugged the Bump output of a Crackle node into the Refraction Shading input. With Transparency set to 0%, the ball only renders as a solid white ball.

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Transparency is set to 50% for the next image, and you can see the wild coloring showing up from the conversion from bump information to color.

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This next image has Transparency set to 100%.

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The bump colors are most intense here, and you can see that the shadow is more colored as well. Refraction Shading overrides the Color Filter, and since I've given it some intense colors, these are used in the shadow as well as to define the color of the surface. I've replaced the color of what would normally be seen through the ball with the bump colors of the Crackle Node, which will only show up wherever the ball is at least partially transparent, as you can see here, where I added a texture to the Transparency channel.

38290

This example doesn't exactly show anything useful for regular applications - it just demonstrates what these shading inputs actually contain; color values. As you play around with them more, you'll get a better feel for them.


He Who Didn't Even Like Nodes At First.

bryphi7
10-27-2006, 12:38 PM
I do think that they should gray the inputs out that are over ridden. They should still let you plug into them to access the buffers if needed. It would at least let people know that it wasn't doing anything.

Thomas M.
10-27-2006, 03:23 PM
It starts to get into my brain. I don't feel it yet, but I probably understand it (if I want to).

The question remains: If I want to have a car lacquer with several layers, e.g. each reflecting with a different blur and different amount (upper layers take away light from lower layers), how do I do this with "your thinking"?

I didn't have any problems to create this stuff in the diffuse shading slot, but if I split it up and need reflection (green) to set the amount of reflection, how does this one parameter can resemble each layer of the lacquer?

BTW, standing ovations for your post.

Thanks
Thomas

P.S.: Same problem with a wet reflecting surface. The wetness adds a second reflection layer. How to seperate the reflection amount with only one green input?

Dave Jerrard
10-27-2006, 04:37 PM
It starts to get into my brain. I don't feel it yet, but I probably understand it (if I want to).

The question remains: If I want to have a car lacquer with several layers, e.g. each reflecting with a different blur and different amount (upper layers take away light from lower layers), how do I do this with "your thinking"? This is where you mix reflection nodes. You can blend two reflections in a mixer, any way you want, and you can mix the output from such a mixer with another reflection with yet another mixer. And each reflection node can have its own bumps, independent of anything else. The same for specular highlights.


I didn't have any problems to create this stuff in the diffuse shading slot, but if I split it up and need reflection (green) to set the amount of reflection, how does this one parameter can resemble each layer of the lacquer? You don't have to limit it to this one paramter. The Reflection and Transparency channels basically turn thee features on and at what 'volume'. But you can tweak the nodes themselves by adjusting the color of each one. The color setting can be used to control how clear or reflective they are - black basically turning them off and white turning them to full strength.

He Who Will Whip Up Some Examples In A Bit.

colkai
10-31-2006, 04:35 AM
Can I just state, officially and for the record?

You guys are making my poor old brain hurt. ;) :p

Seriously, this is absorbing stuff and I think I'm gonna have to print it out to read it.

Dave J, what can I say? you da man.

jmcinnis
12-18-2006, 09:20 AM
Node & Transparency as discussed in this thread in a PDF.

dr01d
01-21-2007, 05:07 PM
nice one jmcinnis, i was just thinking there was a manual or faq in this ;-)

thanx dave, also helping me get my head around it too.