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a link to an example of the desired cement can be found here: How to create and animate the water reflection (Caustics) on an object? Note the cement next to the water....looks realistic, faded, warn, paint chipped,

Also this "cement shader" would of course be added ontop of an image texture(shown belowenter image description here

Above the desired cement...

Below, the result I have so far with just the image texture(yellow+black caution) and basic shader(gloss)enter image description here

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  • $\begingroup$ black/yellow caution cement just looks to fake, any ideas for a more belivable look to the cement would be great....thanks $\endgroup$
    – Matt
    Aug 6, 2015 at 23:55
  • $\begingroup$ Use a grunge/rust image texture (it's generally easier to get more realistic/believable results with an image texture) to mix in darker spots and lighter spots, simulating places where the paint has chipped a little (lighter spots) or is missing entirely, showing the dark cement underneath. You also might want to use a mask to make sure such nicks and scrapes appear in likely places, such as along edges and corners. $\endgroup$
    – gandalf3 ♦
    Aug 6, 2015 at 23:59
  • $\begingroup$ Sounds good (but noob here) how exactly is a mask made or created? $\endgroup$
    – Matt
    Aug 7, 2015 at 0:19
  • $\begingroup$ Run a noise texture with a high detail (at least 5) through an is greater than node for a mask to mix your paint and cement shaders. I don't have time now but I'll add an answer in the morning. This is the technique I used to create the chipped paint in this post. The linked BA thread has a .blend you can download and look at until I get my answer up. $\endgroup$
    – PGmath
    Aug 7, 2015 at 4:40
  • $\begingroup$ I've been doing some experimenting and it seems that the bump mapping is the biggest key. I've tried several different types of bump to get a good concrete look, so far the best looks like a mixture of image texture and two sizes of voronoi. $\endgroup$
    – PGmath
    Aug 8, 2015 at 3:52

1 Answer 1

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Here is what I have been able to come up with:
enter image description here

Here are the nodes:
enter image description here
Click to enlarge.

The shaders:

The bare cement shader is just a mix of diffuse/glossy with a cement image texture controlling the diffuse color and the glossy roughness (after going through a color ramp for fine tuning).

The paint shader is a straight mix of glossy/diffuse with a light, desaturated yellow color on the diffuse shader. On the paint I also use a high contrast grunge texture, sent through a multiply node, to mix in some grunge. For the grunge just send a grunge texture through a color ramp with some grimy colors on a diffuse shader.

The mask:

When paint wares off in real life it doesn't fade out and slowly reveal what's underneath of it, it chips off; it is either there or it isn't. to simulate this I send a noise texture sent through a math > greater than node. The greater than node gets rid of any grey in-between areas.

The bump-mapping:

One of the biggest selling points for realism I have found is bump. The biggest thing to keep in mind is that in real life the paint will conform to the surface it is on. So in your material you want it to use the same bump mapping as the underlying surface (the bare concrete). However it will slightly fill in the crevices and the bumps will not be quite as distinct. To simulate this I use the same bump map for both shaders, but I use a smaller strength on the paint shader. In terms of the bump itself I am using part image texture (same as the one for the bare concrete color), and mix it with two different sizes of voronoi (inverted with color ramps) using two bump map nodes.

Further reference:

  • Here's the .blend file:

    Unfortunately due to license issues I can't include the image textures in the .blend so you will have to use your own.
  • See my answer here for a more detailed look at levels of grunge.
  • Check out this post on BA where I have a very similar shader for chipped paint on wood.
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