Some new shader stuff:

[OnoSendai]

Access to the world space normal of the surface fragment from inside a shader:

normal.jpg (38.24 KiB) Viewed 12122 times

Code: Select all

<diffuse>
			<albedo>
        <shader>
          <shader>
            <![CDATA[	
						def eval(vec3 pos) vec3 :
                  vec3(
                    doti(normalWS()), 
                    dotj(normalWS()), 
                    dotk(normalWS())
                  )
						]]>
          </shader>
        </shader>
      </albedo>
		</diffuse>

Access to the zenith angle of the incident and scattered rays, allowing effects like colour-changing paint:

colour_changing_paint.jpg (74.6 KiB) Viewed 12124 times

Code: Select all

<material>
		<name>default</name>

		<phong>
			<diffuse_albedo>
        <shader>
          <shader>
            <![CDATA[	
						def eval(vec3 pos) vec3 :
                  lerp(
                    vec3(1.0, 0.0, 0.0),
                    vec3(0.0, 1.0, 0.0),
                    thetaMax()
                   )
						]]>
          </shader>
        </shader>
      </diffuse_albedo>

      <exponent>
        <constant>
          10000.0
        </constant>
      </exponent>
		</phong>
  </material>

I'll probably release this stuff after 2.2 stable is done.

[lycium]

rock on i've been wanting to write some ISL shaders for a while...

[psor]

Looking good! I'm wondering if we can create "dirt" shader in the near future too. ;o))



take care
psor

[OnoSendai]

Hi, Psor, what do you mean by a dirt shader?

[lycium]

i think he means something like what you had on your blog (which i miss btw, those rainbow tests etc were awesome), the "dust" shader which blended in some constant "dirty" colour depending on y component of the normal (since dust mostly falls downwards).

[CTZn]

Yeepee !

Sometimes distance/curvature based shaders are refered to as dirt shaders, because they affect small features more. Curvature shaders could be used as blend maps to figure weared corners and stuff... but I'm not sure what psor is refering to

I understand the second pic visually (and that's quite enough) but I'd like to understand more... is this involving the incoming light direction ? If that's the case then the scene is not self-explanatory (light position), either what I don't get the subtlety...

Anyways... very cool stuff Ono !

[OnoSendai]

CTZn: Basically the colour changes as the view direction of a surface moves from the normal direction to grazing direction.

[neo0.]

CTZn: Basically the colour changes as the view direction of a surface moves from the normal direction to grazing direction.

So like iridescence?

[Stromberg]

Realy cool
I see dirt shader like some sort of ambient occlusion, that you could blend and make dirt texture maps appear where the ao is... would be cool to have

[OnoSendai]

CTZn: Basically the colour changes as the view direction of a surface moves from the normal direction to grazing direction.

So like iridescence?

Yeah. I think that's how colour-changing car paint is made.

[djegoo]

wohooooo this efect on this teapot was exactly what i was desperately trying to do tonight by noobishly blending materials (yeah i m not expert ) and no succes!!!!

aaay i m so impatient to have this kind of shader

[juan_irender]

Perfect, Ono! Every add you make to ISL is very, very convenient for Indigo.
Many thanks!

[CTZn]

It's so obvious what the shaders are doing now... I know them !!! Dunno what happened yesterday, brain@sunday or something close for sure.

zeitmeister, is your request: closest to shaded point ?

ie: very close is very dark and vice-versa. Could be used for menisque creation (use a flat water surface in a glass, apply distance shader as displacement. Same applies to displace the soil around a tree), some weathering effects (as AO pass) and more SFX.

Hang on: light gray on all meshes with unform backround lighting, tonemap and go ! You know that already zeitmeister

[psor]

Realy cool
I see dirt shader like some sort of ambient occlusion, that you could blend and make dirt texture maps appear where the ao is... would be cool to have

Yupp, that's how I would explain it too. Maybe a dirt shader needs a few more options tho.
Cause I'd need it to be possible to have irregularities instead being as smooth as AO.

I've to admit that I haven't used a dirt shader for years now as my work was mainly archviz
and they like there stuff clean.

I guess today you call it just AO and that's it. I'm a bit ol' school. ;o))



take care
psor

[Stromberg]

Thanks Psor, for explaining this
And it's what i tought, but maybe with a turbulence option aswell, very usefull