Shaders

[Marc]

Could someone please explain how the following work and what exactly they are:

1. Conducter

a. Ambient

b. Diffuse

c. Specular

d. Roughness

e. Refraction

f. Absorption

2. Dialectric

a. Transmission

b. Refraction

3. Phong

a. Specular Exponent

I have an idea about what these are but what exactly they control (if anything) I have no idea. I've spent the better part of 3 days messing around with this stuff and can't seem to come to any rules about these things.

Any help would be greatly appreciated.

Thanks

M

[Dave Donley]

Hello Marc:

quote:

---

1. Conducter

a. Ambient

b. Diffuse

c. Specular

d. Roughness

e. Refraction

f. Absorption

2. Dialectric

a. Transmission

b. Refraction

3. Phong

a. Specular Exponent

---

1. The Conductor shader is an accurate metallic shader. You can simulate almost any common kind of metal with it if you have the physical constants for that metal (like from a physics textbook).

a. Ambient: Set this higher to make the color shader used with the conductor reflectivity shader more pronounced. For example, if you have a blue marble color shader with a conductor reflectivity shader, setting the ambient value higher will make the blue marble more visible.

b. Same thing for diffuse, but diffuse light is affected by the direction of the light hitting the object.

c. Specular light is the highlight you see on shiny objects. Set this value higher to make the highlight brighter/more pronounced.

d. Roughness: set this higher to make the metal seem more soft/dull/brushed rather than hard/shiny.

e. Refraction: These are physical coefficients that define the behavior of light on metallic surfaces. You need a physics reference to set these values reliably.

f. Absorption: Same thing.

2. Dielectric: This is an accurate glass shader.

a. Transmission: Basically the same thing as transparency, set it higher to make the material more transparent.

b. Refraction: Different transparent materials bend light more or less compared to other materials. For example, diamond bends light more than glass, which bends light more than water. Set this higher to bend the light more.

3. Phong: This is a basic shiny shader, invented by a dude named Phong.

a. Specular Exponent: This value sets the sharpness of the specular highlight on shiny-looking materials. The higher this value is, the more "hard" the object will look. If you set it high the object would tend to look like a pool ball, lower values and it would tend to look like soft plastic.

BTW, In RW 10 there is a help view in the edit shader dialogs that kind of describe the parameters better. There is also an appendix in the RW 10 manual that describes the shaders and their parameters pretty well.

HTH,

[Marc]

Thanks a bunch Dave.

That helped out emensely!

M