Materials tutorial? And how to make wax

[Zedd]

Hi. I started this thread on blenderartists: http://blenderartists.org/forum/showthread.php?t=150227 and basically would like to know if there's any in-depth material tutorial, possibly with examples of how to make different materials.

Also, it would be great if anyone knew how to make realistic wax/paraffin.

[PureSpider]

Wax/paraffin is basically simple colored glossy transparent with SSS on
Just play around with the strenght of the scattering/absorption until you're happy

This is some simple green Wax for example:

Code: Select all

    <medium>
        <name>MedSSS green</name>
        <precedence>10</precedence>
        <basic>
            <ior>1.50000</ior>
            <cauchy_b_coeff>0.00000</cauchy_b_coeff>
            <absorption_coefficient_spectrum>
                <rgb>
                    <rgb>200 50.196 100.392</rgb>
                    <gamma>1</gamma>
                </rgb>
            </absorption_coefficient_spectrum>
            <subsurface_scattering>
                <scattering_coefficient_spectrum>
                    <uniform>
                        <value>500</value>
                    </uniform>
                </scattering_coefficient_spectrum>
                <phase_function>
                    <uniform />
                </phase_function>
            </subsurface_scattering>
        </basic>
    </medium>
    <material>
        <name>SSS_green</name>
        <glossy_transparent>
            <internal_medium_name>MedSSS green</internal_medium_name>
            <exponent>
                <constant>200</constant>
            </exponent>
        </glossy_transparent>
    </material>

[Zedd]

Thanks, i think i've managed to make a decent(ish) looking wax. Still, a material tutorial or in-depth explanation could prove handy.

[PureSpider]

Just ask what you want to know and I'll try and answer it

[neo0.]

If I might inject my own tip here..

Notice this part of the code?

Code: Select all

 <rgb>200 50.196 100.392</rgb> 

This is what determines the color of the wax. To change the color, just open photoshop and plugin the rgb tiplets for a different color. Basically what we have here is a shader that absorbs light.. Now, depending on which wavelengths it absorbs, the end result will be a different color.

I wish it were easier though.. I wish indigo could some how take your shader code and give you a graphical way to edit it directly. .. Like it would find the above part, where the rgb is, and when you click on it, it would pop up a color picker. Or it would find the sss part, and pop up 3 sliders for each of the 3 rgb colors for the full spectral absorption. Sort of like smart code editing. You would still have to write it by hand, but the revision process would be much simpler and thus much less error prone.. Much closer to the visual worflow of using the material editor.

Indigo's shader code can be pretty confusing at first (i havent even learned all of it yet), but it's a lot like html..

Indigo does lack a documentation of it's shader types (phong, sss, etc.).. but this is what I know

Phong : Good for making shiny things. Plastic, carpaint, etc. Antthing that is glossy or reflective.

Specular transparent : good for glass and.. plastic maybe? Try creating a blend material with it and a null and playing with the blend ratios.

Glossy transparent : not quite sure what it is.. When I need glass, I just use specular.

SSS : absorbs different wavelengths of light. The thicker an object is, the more it will absorb, and the less light will get out making it darker.

Metals : Use NK for more realistic "official" metals, or use a non nk to make whatever color metal you want.

Oren naylor : No clue what this one does.

In addition, many of these material types can be augmented by textures
Bump map : for phong and diffuse materials. Creates the illusion of depth.

Displacement map : Like a bump map, except it actually effects the geometry.

Exponent map : can be used with phong to create shiny tiles. Thing of this as the tiles themselves and the phong ads the shinyness.

All these can also be combined to your hearts content with blend materials.

It takes time to learn, but i got better results with indigo after 5 minutes than i did with kerkythea after a week. Kerkythea was a headache..

[SATtva_]

I wish it were easier though.. I wish indigo could some how take your shader code and give you a graphical way to edit it directly.

This is what exporters are made for.

Glossy transparent : not quite sure what it is

Specular transparent gives you materials with perfect reflectivity like clear glass. With glossy transparent you can create things like milky glass with blurred transparency and phong-like reflections.

SSS : absorbs different wavelengths of light

Not only absorbs, but also spreads it inside the medium.

Oren naylor : No clue what this one does

Oren Nayar actually. This is for hard materials like clay, or stone.

Did you tried to look into the official reference guide ("Indigo Manual.pdf" in the installation directory)? There you'll find every material description along with accepted parameters.

Kerkythea was a headache

Precisely.

[neo0.]

Wow, you really live in siberia?

[SATtva_]

:D Yep, along with 20 millions of other people.

[neo0.]

lol, I pictured bears and snow when I read siberia.

[SATtva_]

Don't be the prisoner of stereotypes. ;)

Now back on topic.