Paint splooch

[mattjgerard]

I having trouble getting this paint splooch on a rock to look better. Not sure if its the lighting, or what, but the center of it looks ok with the bump of the rock coming through the label, but the edges of the paint look unattached to the rock. looks like its floating. I know it could use some thickness, but since its just a label I'm wondering if there is a way to create a slight reflection around the outside perimeter of the splooch using occlusion nodes or something tricky in the matgraph. I tried using several maps in a bump add node trying to somehow get the outline of the splat to create a map from. Next is to go into photoshop and make a height map from the outline and somehow use that, but I'm shooting in the dark and not sure it would even work.

Any ideas? I could go  and model the splat with some thickness, but would be cool to figure out how to get just that little thickness edge on other labels as well.

[RRIS]

I'd remove the roughness input on the paint.. you'd probably want your rock to be rough and the paint to be more reflective.
Also, take that paint splat in Photoshop and blur it on the inside (I typically use a photoshop layer effect... inner glow. Set the blending mode to normal and use a black).
Basically you want to raise the spot a little around the edges.
Also for the paint opacity, use a black/white mask. Just as a good habit, use your colored image only for the diffuse map.
Then I'd look at the environment, take something contrasty.. right now it almost looks like you're lighting the scene with an overcast environment, which makes it really hard to see any reflections, highlights, etc.

[mattjgerard]

Thanks for the tips, going to try those on my lunch hour. I figured I was going to have to create something new in photoshop , a map or blurred something to help define the edge. I'm applying labels of many kinds to products all the time, and trying to figure out how to give those labels a little bit of thickness procedurally within keyshot would be pretty dang cool.

[Will Gibbons]

I can't help but notice what looks to be a fairly low-contrast HDRI. Make sure you've got some bright light sources and some contrast in your HDRI if not using physical lights. Be sure to have some reflection showing the contrast between the rough rock and more glossy paint.

[bdesign]

Hey Matt-

Speaking specifically to your paint splatter label, I second what RRIS and Will have stated. Definitely need that raised edge with falloff for the splatter, and contrast between the rock and paint. In the paint splatter example render below, a normal map for the paint material was created from a slightly gaussian blurred copy of the opacity map. "Apply Bump To Labels" is enabled for the rock material, and to make the underlying bump less defined beneath the paint splatter, a Bump Add utility node was used to combine a sharp + gaussian blurred version of the same rock bump map, using the splatter map as a mask for Weights 1 and 2.

For clean edged product labels with which you frequently work, you can use a duplicate (right-click > Duplicate) of the Diffuse map as a bump map, as long as the color value is above 0%. In the example render below, the same type Bump Add node setup used with the rock material was used to achieve a less defined underlying surface bump beneath the label graphic, with a Color Key Mask used as a mask for Weights 1 and 2.

Cheers,
Eric

[mattjgerard]

interesting stuff, so the Color Key Mask node is generating the black and white map based on the color selected in the node?

If so, what is the function of that map going into the weight port of the bump add? What does the weight control do different than the ratio? Is it a per-pixel weight control rather than an overall control of the mix?

[bdesign]

interesting stuff, so the Color Key Mask node is generating the black and white map based on the color selected in the node?

Yes, exactly. For multi-colored textures the Threshold value acts like the Tolerance value for the Magic Wand tool in Photoshop. The Fuzziness value acts like the Fuzziness value for the Select Color Range function in Photoshop.

If so, what is the function of that map going into the weight port of the bump add? What does the weight control do different than the ratio? Is it a per-pixel weight control rather than an overall control of the mix?

As I see it, with the Bump Add node, the Ratio value acts rather like a "bump opacity" for blending between the texture inputs. The default value of .5 means the effect of each input is equally visible.

The Weight 1 and 2 values control the overall bump height of the texture inputs. With two textures being combined, the Bump Height value of each as set directly within their respective Texture Map nodes will essentially be reduced by half when the Weight 1 and 2 values are at the default of 1. This is why, when chaining multiple Bump Add nodes together, I will set the Weight 1 value at 2 for each successive node in the chain to retain the effect of the previous node in the chain.

With that being said, I could have acheived the same effect in this case by plugging the Color Key Mask into the Ratio channel, and setting Weight 1 and 2 values at .5, thus eliminating one extra node in the matGraph (the Color Invert node).

Below are a few region renders of just the underlying material with different setups. 

1. Weights 1 and 2 mapped with Color Key Mask, Ratio at default value of .5
2. Ratio mapped with Color Key Mask, Weight 1 and 2 at value of .5
3. Ratio mapped with Color Key Mask, Weight 1 and 2 at default value of 1

Cheers,
Eric

[bdesign]

An additional fine detail effect that can give the labels a slight bit more dimensionality is to simulate a self shadow for the normal map by duplicating the label Diffuse texture, offsetting the Shift X and Shift Y by a micro amount, and using this texture to create a map for the Value channel of a Color Adjust node. A reference object (such as a cube placed at scene center) can be used as a visual guide for how shadows fall in the scene, to determine the offset X and Y directions.

Plug the label texture > Color of a Color Adjust node. Plug the Color Adjust node > Diffuse of label material. Plug the offset duplicate into a Color Key Mask. Plug the Color Key Mask > Input of a Color To Number node. Set the Output From value to .5, Output To value to 1. Plug the Color To Number node > Value of the Color Adjust node. Tweak the Output From value to obtain the desired "self shadow" density.

It's a very subtle effect, but can make the label "pop" just a bit more.

Example renders are:

1. Label with effect
2. Label without effect
3. Underlying surface only, with effect
4. Value map for Color Adjust node

Cheers,
Eric

[BasTel]

Hey Matt,

Esben did a tutorial on this I think.
Maybe this can help.  -->  https://www.youtube.com/watch?v=XfSiac7Lw2I

Sebastisan