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I recently saw Andrew Price's tutorial on how to do realistic texturing. At the end of the tutorial he said something along the lines of needing to just "add scratches" to increase the realism. How do you simply add scratches? I understand that there are probably multiple methods, and I am interested in hearing as many as possible. Thank you.

Anson Savage
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2 Answers2

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The way Todd is completely right,but you can go even complex for scratches,like using the pointiness feature in blender,here I used two different scratches texture to do the material,check the node tree for more information. The material

enter image description here

Omar Emara
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I would just find an appropriate image texture of scratch marks, and then use that as a factor in mixing your diffuse and glossy shaders. You could also use the same texture as a subtle bump map factor.

In the screenshot below, I'm combining the scratch texture with a fresnel effect before using that output as a mix factor between the diffuse and glossy shader nodes.

You can find lots of scratch textures at http://www.cgtextures.com

enter image description here

Todd McIntosh
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  • Superb answer! I might also add that if you had a normal map of those scratches you could take the effect even further by plugging it into the displacement input on the shader. Upvoted. – Ross M. Jun 09 '15 at 20:02
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    Thanks Ross. I would say that it would be unlikely that you would use these types of scratches for displacement. They are so fine, bump map would be the most appropriate usage. If you texture had large gouges in it, perhaps displacement would be useful. – Todd McIntosh Jun 09 '15 at 20:03
  • Thank you for your answer! The only part I didnt understand is the purpose of the texture coordinate node, and the Fresnel node. Thanks. – Anson Savage Jun 09 '15 at 22:04
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    Hi Anson, I used the object tex coords because I was too lazy to UV unwrap the sphere. The fresnel effect is not necessary for the scratch effect, it just looks nicer. What it does is change the dif/glos mix based on the surface angle to the camera. This mimics what many curved surfaces do in real life which is increase the glossiness nearer the edge. – Todd McIntosh Jun 10 '15 at 00:38
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    Also, I should have just used one text coord vector instead of Generated and Obj, but that wasn't the point of the screenshot, so I guess it's okay to leave it. – Todd McIntosh Jun 10 '15 at 00:39
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    @AnsonSavage Also if the answer works for you please mark it as the official answer. Thanks! – Todd McIntosh Jun 10 '15 at 00:49
  • Should probably add a change in roughness because it looks like a material that was scratched and then glossed over. – Anson Savage Feb 03 '18 at 01:28