ISL help

[chubakueno]

I'm working on a shader that blend towo textures with the "burn" equation. The problem is that I need to divide two vec3's and Indigo doesn't have that feature.¿Someone can help me?
I = Top Layer
M =Back Layer

[fused]

Hey, I really want to help you, but I'm not sure how the division should work.

Read this: http://www.mcasco.com/qa_vdq.html

In vectors there are two ways of multiplying, the dot product and the cross product.

[...]

dot division is not defined.

[...]

cross division is also undefined.

[chubakueno]

I mean tex1 (r1,g1,b1)/ tex2 (r2,g2,b2) = result (r1/r2,g1/g2,b1/b2)

[fused]

okay, here we go:

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def div(vec3 a, vec3 b) vec3: vec3(doti(a) / doti(b), dotj(a) / dotj(b), dotk(a) / dotk(b))

another question of understanding: are the components assumed to be in the range of 0-255 for this function?

[chubakueno]

Yes, but it can be easily converted from 0-255 to 0-1. I'm testing...

[chubakueno]

Thanks Fused, it works!
Now I'm doing overlay, screen, etc
edit:: I think blending modes can be bundled into exporters.

[Zom-B]

Thanks Fused, it works!
Now I'm doing overlay, screen, etc
edit:: I think blending modes can be bundled into exporters.

Nice work chubaka,

I'm sure if you release your code you could speed up the Exporter integration

[fused]

Thanks Fused, it works!
Now I'm doing overlay, screen, etc
edit:: I think blending modes can be bundled into exporters.

Nice work chubaka,

I'm sure if you release your code you could speed up the Exporter integration

Oh yes!
If you post all your shader when youre done it will make its way into the ISL blend shader in cindigo

[chubakueno]

Overlay:

isl_camo_overlay.jpg (96.6 KiB) Viewed 15065 times

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						<![CDATA[
					def overlay(real it1, real jt1, real kt1, real it2, real jt2, real kt2) vec3:
						vec3(div(mul(div(it1,255.0),add(it1,mul(div(mul(2.0,it2),255.0),sub(255.0,it1)))),255.0),
							div(mul(div(jt1,255.0),add(jt1,mul(div(mul(2.0,jt2),255.0),sub(255.0,jt1)))),255.0),
							div(mul(div(kt1,255.0),add(kt1,mul(div(mul(2.0,kt2),255.0),sub(255.0,kt1)))),255.0)
							)
					def eval(vec3 pos) vec3 :
						overlay(
						doti(sample2DTextureVec3(0,getTexCoords(0)))*255.0,
						dotj(sample2DTextureVec3(0,getTexCoords(0)))*255.0,
						dotk(sample2DTextureVec3(0,getTexCoords(0)))*255.0,
						doti(sample2DTextureVec3(1,getTexCoords(0)))*255.0,
						dotj(sample2DTextureVec3(1,getTexCoords(0)))*255.0,
						dotk(sample2DTextureVec3(1,getTexCoords(0)))*255.0
						)
						]]>

Normal:

isl_camo_normal.jpg (105.78 KiB) Viewed 15065 times

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						<![CDATA[
					def substract(real it1, real jt1, real kt1, real it2, real jt2, real kt2) vec3:
						vec3(div(add(mul(it1,0.5),mul(it2,0.5)),255.0),
							div(add(mul(jt1,0.5),mul(jt2,0.5)),255.0),
							div(add(mul(kt1,0.5),mul(kt2,0.5)),255.0)
							)
					def eval(vec3 pos) vec3 :
						substract(
						doti(sample2DTextureVec3(0,getTexCoords(0)))*255.0,
						dotj(sample2DTextureVec3(0,getTexCoords(0)))*255.0,
						dotk(sample2DTextureVec3(0,getTexCoords(0)))*255.0,
						doti(sample2DTextureVec3(1,getTexCoords(0)))*255.0,
						dotj(sample2DTextureVec3(1,getTexCoords(0)))*255.0,
						dotk(sample2DTextureVec3(1,getTexCoords(0)))*255.0
						)
						]]>

Invert:(only the camouflage)

isl_camo_inv.jpg (74.98 KiB) Viewed 15064 times

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						<![CDATA[
					def  substract(vec3 col1, vec3 colt) vec3:
						sub(col1,colt)
					def eval(vec3 pos) vec3 :
						substract((vec3(1.0)),
						sample2DTextureVec3(0,getTexCoords(0)))
						]]>

edit:Later I'll post the other blending modes

[fused]

wow, pretty nice, a few nitpicks if you dont mind

in the invert shader, you dont really need a subtract() finction. i fact you dont even have to use the sub() function. just use operators:

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def eval(vec3 pos) vec3 :
                  vec3(1.0) - sample2DTextureVec3(0,getTexCoords(0))

in the other two shaders:

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doti(sample2DTextureVec3(0,getTexCoords(0)))*255.0,
dotj(sample2DTextureVec3(0,getTexCoords(0)))*255.0,
dotk(sample2DTextureVec3(0,getTexCoords(0)))*255.0,

is the same thing as

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sample2DTextureVec3(0,getTexCoords(0)) * 255.0

and then passing that to the overlay/subtract function.

a few other optimizations/simplifications for your normal shader:

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def div(vec3 a, vec3 b) vec3: vec3(doti(a) / doti(b), dotj(a) / dotj(b), dotk(a) / dotk(b))
def substract(vec3 v1, vec3 v2) vec3:
                     div((v1 * 0.5) + (v2 * 0.5), 255.0)
                     )
               def eval(vec3 pos) vec3 :
                  substract(
                  sample2DTextureVec3(0,getTexCoords(0))*255.0,
                  sample2DTextureVec3(1,getTexCoords(0))*255.0
                  )

not tested tho

[chubakueno]

Yes, but you can't divide a vec3 with a real.edit:And thanks for the optimizations.

[fused]

Yes, but you can't divide a vec3 with a real.

easy fix

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div((v1 * 0.5) + (v2 * 0.5), vec3(255.0))

or:

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def div(vec3 a, real b) vec3: vec3(doti(a) / b, dotj(a) / b, dotk(a) / b)

[chubakueno]

In general, you can't divide vec3's, only real vs real

[fused]

sorry but that is what you asked for in the beginning. then I told you its not possible and you said what you meant. Then I wrote a function that does exactly that. And now you tell me its not possible.... hello?

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def div(vec3 a, real b) vec3: vec3(doti(a) / b, dotj(a) / b, dotk(a) / b)

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def div(vec3 a, vec3 b) vec3: vec3(doti(a) / doti(b), dotj(a) / dotj(b), dotk(a) / dotk(b))

[Stinkie]

Neeeerd fiiiight!