how to do gradient textures?

Heavily Tessellated · Post by **Heavily Tessellated** » Sun Sep 09, 2007 3:07 pm

So, how would I go about making a smooth gradient from clear glass to full mirror?

Thinking I knew what I was doing

I threw in three textures, one Specular glass, one Phong mirror, and one placeholder for the BLENDED, mapped to the object in question... I set the A/B textures respectively, loaded a black -> alpha clear gradient bitmap as the bumpmap and turned it loose...

Well. I guess I have no idea what I'm doing. The rendered output was not un-lovable, it was kind of a "super" glass (more reflective than normal glass but still quite transmissive) but this is far from what I was after. I just wanted a plain glass to fade into a mirror.

I searched, but found nothing. I have to assume there's got to be a way to do it, short of breaking the mesh into micro-sized faces where I want the gradient and having to do it manually...

Any pointers or links would be great, thanks!

zsouthboy · Post by **zsouthboy** » Sun Sep 09, 2007 4:16 pm

Blend maps are unsupported for specular materials.

Heavily Tessellated · Post by **Heavily Tessellated** » Sun Sep 09, 2007 5:51 pm

Are you sure about that? I could have sworn I saw a pyrex beaker with index markings on it, from a blended material setup.

But OK, so if it's not supported, what can I do to get around it? Maybe make an environment map from the object's perspective in Blender, bake that texture, and layer it? Granted the reflections won't be as purdy as if Indigo did it, but does it seem feasible?

DaveC · Post by **DaveC** » Mon Sep 10, 2007 4:21 am

What you have to do is created your two materials (like you already did), mine are both specular, and create a white to black gradient in a paint package (ie, gimp) and uv map it to the object in question. Then, create the blend material with A as glass, B as mirror and blend map is the gradient you created and mapped. It should work.

I tried a quick test and it seemed to work. I'll post results as soon as they're clear.

Kram1032 · Post by **Kram1032** » Mon Sep 10, 2007 4:27 am

there are or where problems with the colour of glass and stuff... I'm not entirely sure, whether it was fixed or not, but if you blended something with glass, the glass lost it's own colour, I think...

Heavily Tessellated · Post by **Heavily Tessellated** » Mon Sep 10, 2007 3:06 pm

Hmm. Well, another attempt. And yes, apparently blending glass with non-glass breaks something... the phong mirror got turned instead into a black-ish glass. I switched the black -> alpha clear to a regular black -> white gradient bitmap for the bump, but as you can see it had zero effect. So while the mirror got turned into a dark glass and the clear glass came out as clear glass, the blended section where the mirror should have faded into the regular glass is, well, a blended texture of both about 50%. So the actual BLENDED part working fine, it's just ignoring the matte. Maybe it doesn't work like this, just as a whole - sans gradient?

Triode test 4 (with heaters glowing about 2500% more than they should)

Moses · Post by **Moses** » Mon Sep 10, 2007 6:54 pm

Try duplicating the mesh and leaving only the area of the glass you want to be a mirror
also make it one wall(no thickness), then place it inside the thickness of the original glass.
Instead of using blend use a gradient alpha map to transition the mirror to glass.

CoolColJ · Post by **CoolColJ** » Mon Sep 10, 2007 7:44 pm

oooh valves, I love em for audio work, when I'm engineering

Heavily Tessellated · Post by **Heavily Tessellated** » Mon Sep 10, 2007 9:41 pm

Moses wrote:Try duplicating the mesh and leaving only the area of the glass you want to be a mirror
also make it one wall(no thickness), then place it inside the thickness of the original glass.
Instead of using blend use a gradient alpha map to transition the mirror to glass.

Ahh... duh. I get it, embed the mirror texture beneath the glass, and just gradient it from solid to alpha transparent. No blending, just missing mirror...
Bingo. I bet that'll work perfectly. Thanks for pointing out the least technical way, too.

Heavily Tessellated · Post by **Heavily Tessellated** » Tue Sep 11, 2007 6:49 pm

Works as directed. Thanks again.

Kram1032 · Post by **Kram1032** » Wed Sep 12, 2007 3:51 am

looks nice

- on the bottom, where it stands on glass "legs", you have normalsmoothing artefacts... use more polys, there

(Subsurf)

Heavily Tessellated · Post by **Heavily Tessellated** » Wed Sep 12, 2007 7:13 am

yea I see it, heh but let's not restart that, you know me and glass... also the connecting wires beneath the SSS insulator wafers are phong silver but render black? I can't imagine what it's reflecting black from, it's just sunsky and a plane... but this was just about graduated mirroring, and that worked just dandy.

CoolColJ · Post by **CoolColJ** » Wed Sep 12, 2007 10:47 am

maybe reversed normals?

Heavily Tessellated · Post by **Heavily Tessellated** » Sat Sep 15, 2007 6:35 pm

aggg... no. It's just dumbass me not checking Blendigo carefully enough... its one of those "it did exactly what I told it to." things...

Kram1032 · Post by **Kram1032** » Sat Sep 15, 2007 10:01 pm

lol, what did it do? xD

how to do gradient textures?

how to do gradient textures?

Who is online