# How to make just one color of my texture bright (like as metallic)?

I am modeling an object that has a label. The label I applied as a texture (a single image), and made an unwrap normally, as follows the render below.

However, I need the yellow part of this texture to have a shine (as metallic), just like the real product (as follows the photos on links below).

How can I make only the yellow parts of my texture (label) emit this glow effect? I am modeling and texturing using Blender 2.81.

I am using only one image to texture the label. Do I need a second image with only the yellow parts to do this?

• If you're animating the presentation, the best is a metallic shader on that yellow color. But if you will just show a render, the best is to fake that brightness using any photo editing program. – LeoNas May 6 '20 at 2:05
• Now I have another problem. I need to make two yellow parts shine, in different tons. Like this: queensberry.ind.br/wp-content/uploads/2019/12/… and this queensberry.ind.br/wp-content/uploads/2019/12/… At the top of the label, there is a yellow one inside the other. And both need to "shine", but one more intensely than the other. How can I do this? – Gabriel Magalhães May 12 '20 at 11:35
• I think it's better you make a new question. – LeoNas May 16 '20 at 3:17

I use a distance vector math node, which tell blender to find the color in that image, with RGB (1.0, 1.0 ,0.0)(which is yellow).

And then continue with a compare node to see if color is yellow with some ambiguity.

(the second value is compared value, set to 0.0 means same color. the third one is tolerance, change it yourself to see the effect)

Using this mask, you can do a lot of thing with it, you can change the metallic value using this mask and invert it to make it look like mirror in roughness setting.

More complicated setting:

• no need of photoshop and other texture, but keep in mind that this will potentially slow down the rendering time. (Although the math here is super simple and modern hardware can handle it like a piece of cake) – HikariTW May 6 '20 at 2:10
• this is pretty neat, I should start learning blender shaders. I would probably had to make roughness texture, metalic texture on top of a base color texture, but this is simple and faster. – Fowl May 6 '20 at 6:31
• It worked really well. Great. Thank you very much for your time. But now I have another problem. I need to make two yellow parts shine, in different tons. Like this: queensberry.ind.br/wp-content/uploads/2019/12/… and this queensberry.ind.br/wp-content/uploads/2019/12/… At the top of the label, there is a yellow one inside the other. And both need to "shine", but one more intensely than the other. How can I do this? – Gabriel Magalhães May 12 '20 at 11:34
• Then you need to mask that thing out again with this process, and assign it a different setting of gold like material values. Maybe a darker yellow color with less roughness on it – HikariTW May 12 '20 at 14:09
• I understood that I need to do the same nodes, but using the other yellow tone as my mentalist mask. And configure the new gold (metallic) as I need. But how can I put these two materials together after this? – Gabriel Magalhães May 13 '20 at 4:08

If your sticker's border is an image texture then you would have to modify the image in photoshop or something like that. If it is not then you can select the vertices around the border and assign them to a specific material in which case is his metallic one. However if you look at the image the metallic looks fake. As if there is no light shining off of it but the light has been drawn on. So if it is not an image texture use a musgrave texture in the node editor. Hope this helps!

All you need is to create a mask so that you can create a glossy shader for that part of the label. The label never "emits" light, it reflects it. So what is important is to create bright elements and place them in a way that they can be seen reflected on the object.

I'm sure there are plenty of other posts covering this topic.

Here are a few

How can I get the bottle glossy W/O the label too?

Cycles mixed material

Why does an object with a glossy shader render in black?

How can I render objects with very shiny surfaces?

• Why using a Glossy shader when the label is clearly metallic paint? – HikariTW May 6 '20 at 2:14
• Use whatever glossy, metallic, shiny, low roughness, or whatever you want to call it.. the mask will determine what part of the material is that reflective... – susu May 6 '20 at 2:42