Original subtitles

Now we have some texture in the color,

but let's make it more grungy by darkening low spots in the displacement,

to emulate something like a fake ambient occlusion, or just dirt stuck in the crevices.

So let's start by taking the displacement texture we used for the brick surface.

Then let's add a Map Range to put the texture in the range we need.

We actually have this Reroute of the same value much closer, so let's connect it here instead.

Now let's set the input range so that we're not clipping at either side of the texture.

Basically we want to lower the min until we no longer see large black areas.

Then we also want to lower the max until we are filling the zero to one range.

Here it's more difficult to see when we start clipping,

so a good trick for finding the upper bound is to invert the output,

so that the maximum value maps to zero. Now we can easily see when we start clipping to black.

This seems good enough, so let's switch the output range back. Then let's make some space

in the Color Frame so that we can fit this new texture component in there.

We want to affect the value again, to darken the low spots,

so let's duplicate one of these multiplications, and connect it in there.

Now, if we take a look at the color, we see that the chipped bits in particular, get a lot darker.

Then we can also take a look at the shader output, to see it in context.

And let's just tidy these nodes a bit as well.

Maybe going completely to black at the darkest spots is a bit extreme,

so let's increase the Min output a bit.

We can also include this texture in the roughness computation,

so that the parts darkened by this texture also get less shiny. Let's add a Math node,

and we can just multiply this texture into the input of our roughness mapping. Then the darker

parts will have lower values, which in turn get mapped to a higher roughness by the Map Range.

Toggling this multiplication with the M key, reveals the difference this makes.

Now that we are using multiple nodes to compute the roughness, let's not leave

them floating there, so let's frame them with Ctrl+J, and let's label it Roughness.

And then we can give this node a distinct color, to indicate that it's a different

component in our color texture. We haven't used blue yet, so that should work.

Now, just for fun, we can toggle the two nodes that multiply the textures into the color value,

to see the difference before and after these two past chapters.

The bricks are really starting to look a lot more interesting with the textures,

but we've darkened it considerably, so let's tweak the color a bit.

And that's another chapter down.