In this beginner-level tutorial, we will see how to assign two different materials to different parts of a single object that has only one Texture Set, meaning an object provided as a single geometry with just one Material. To assign different Substance Materials to various parts of the same geometry, we will use masks.
Video Transcript
Hello everyone! In this beginner-level tutorial, we will see how to assign two different materials to different parts of a single object that has only one Texture Set, meaning an object provided as a single geometry with just one Material. To assign different Substance Materials to various parts of the same geometry, we will use masks.
Let's begin by creating a new Substance project using the “PBR Metallic Roughness” template and, of course, importing the model we want to use.
Let's take a look at the model I'm using for this tutorial. First of all, notice that the Texture Set List contains only one entry, “can_opener_2”, so the 3D model is effectively provided as a single object with one Material, and it will be our task to assign different Substance materials to the various parts of the object.
From the viewport mode selector in the top-right corner of the 3D view, choose “2D Only” (shortcut F3) and center the UV layout in the frame by pressing the F key, which stands for “frame”.
Notice that the UV layout has been created quite well. It has no overlapping parts, meaning it is “non-overlapping”, and it is easy to identify the handle at the bottom, separated from the metallic parts. Finally, and this is an important detail, the surfaces are properly oriented, especially horizontally. This is useful because some Substance materials feature grain patterns, as we will see, usually oriented vertically or horizontally.
Since the UV layout surfaces are straight, it will be quite easy to orient the material grain on the object.
Let's go back to the 3D view, select “Layer 1” in the Layers panel, and remove it by clicking the trash can icon in the panel. This layer would allow us to paint freely on the object, but that's not what we are interested in right now because we want to use a native Substance material.
Now select “Materials” in the Shelf panel, then type “wood” into the search field. Substance will filter the results and, among the available materials, we should find “Wood American Cherry”.
Maybe this is not the most suitable material for this handle, but at least in the 2019 version of Substance it is one of the materials included by default with the software, so you should have it available. In other tutorials we will see how to add materials downloaded from Substance Source or how to create our own Smart Materials. Here, we will simply use a material included out of the box.
Click the material to select it, then drag it into “Layers”. The material will be applied to the entire object.
Notice that the wood obviously has grain patterns, and they are correctly oriented thanks to the orientation of the UV layout we examined earlier.
With the material selected in Layers, let's take a look at the “Properties - Fill” panel, which you can enable from “Windows” - “Views” if it is not already visible.
This panel is basically the identity card of the currently selected material or, as we will see in other tutorials, filters, masks, and so on. In general, it displays the properties of the selected object.
For materials, the panel includes at least two sections: Fill and Material.
The Fill section contains settings common to all materials. These are parameters related to mapping and projection of the material onto the object. The Material section, instead, contains both settings common to all materials, such as selectors for the information channels affected by the material, like Color, Height, Roughness, and so on, and settings specific to the currently selected material. For example, for “Wood American Cherry” we have controls for the wood color, roughness, grain, and other distinctive characteristics.
In the Fill - Projection section, notice for example that the material is projected onto the object's surface by default using the UV mapping provided with the model, which is why the properly oriented UV seams we saw earlier in the 2D view are so useful.
To change the orientation of the material on the UV mapping, we can keep “UV Projection” and simply adjust the Rotation parameter further below.
To increase or decrease the density of the grain patterns on the surface, we can instead modify the Scale value, meaning the scaling factor of the material on the UV map. Decreasing this value enlarges the material, while increasing it makes it smaller, so Substance will repeat it multiple times across the UV map to cover the entire surface. This happens because the UV Wrap option is set to “Repeat”, and it can produce a tiled effect.
Let's set Scale to 3, for example. This gives us denser grain patterns without making the texture look too tiled.
Looking at the object's surface from different angles, we can notice that the material also introduces lighting effects inside the grooves, simulating depth even though the object's geometry is actually smooth. We can verify this by temporarily disabling the material using the eye icon next to “Wood American Cherry” in Layers.
In Substance, surface relief is mainly simulated through the Normal and Height channels. Since the “Nrm” checkbox in Properties - Fill - Material is disabled, the effect must be generated by Height. We can verify this by toggling that checkbox on and off and observing the result in the 3D view.
We can appreciate the difference more clearly by setting the viewport display mode to “Normal + Height + Mesh” from the top-right corner of the 3D view, then toggling the Height channel on and off again in Properties - Fill - Material.
So yes, it is definitely the Height channel. The “Wood American Cherry” Substance material includes information for this channel, and it also allows us to adjust its intensity. In Properties - Fill - Material, open the Parameters section and modify the “Height Range” parameter while observing the differences in the 3D view, preferably using Material view mode and side lighting on the object.
In this tutorial we will NOT go through every single parameter, because that would become a rather boring and not very useful list. Instead, in future tutorials we will explore various settings and combinations through practical examples, which are much more interesting. Of course, nothing prevents you from experimenting with the parameters yourself if you want to start exploring the available options and their effects.
Alright, we have added a first Substance Material to our Texture Set and explored some of its parameters, but this material is applied to the ENTIRE object, while we only want it on the handle. How can we do that?
The simplest method is to add a mask to the material.
A mask is a grayscale image mapped onto the object's UV layout. It applies the material to white areas and ignores it in black areas, applying it proportionally according to the gray level at each point on the surface.
Masks are extremely important in Substance Painter, both for simple operations like this one and for applying complex effects combined with filters and other operators, for example to simulate edge wear or rust appearing only on certain parts of a surface.
Masks can also be created starting from an external image, but in our case it will be enough to start with a black mask and make only the handle area white.
To create a black mask for the “Wood American Cherry” material, right-click the material in Layers and choose “Add Black Mask”.
A black square will appear next to the material preview, representing the new mask. The mask is currently selected, notice the selection outline around the black square, and in the “Properties - Fill” panel we now see different settings from those of the material itself, which we can still select by left-clicking its preview in Layers. In the 3D view, the object now appears gray and without effects because the material is currently absent from every part of its surface.
There are several ways to make part of the mask white, both manual and procedural, meaning generated by algorithms. In this tutorial we will use a manual method consisting of selecting the UV island, meaning the portion of the UV layout that we want to make white.
With the black mask selected, click the “Polygon Fill” icon, which should now appear in the Tools panel. If needed, you can enable this panel from Window - Toolbar - Tools.
In the “Properties - Polygon Fill” panel, select the checkerboard icon called “UV chunk fill”. This mode allows us to modify an entire UV island simply by clicking on one of its points.
Make sure “Color” is set to white, then click on a point of the handle. The mask will become white on the corresponding UV island, which we can also verify by switching to the “3D | 2D” display mode in “Mask” mode. The result is also clearly visible in Material mode thanks to the appearance of the material.
NOTE: You can also click directly on the UV layout in the 2D view. To demonstrate this, I am undoing the previous operation using the CTRL Z shortcut, or “Undo” from the Edit menu, and with the mask selected and UV Chunk Fill mode set to white, I am clicking directly on the UV layout in the 2D window.
At this point, we can add another material by selecting it from Materials and dragging it below “Wood American Cherry” so that it appears on the remaining parts of the object, right?
Well, yes, that's correct, but there is a small problem that becomes especially noticeable with materials that include other Normal or Height effects, such as “Iron Brushed”, meaning brushed iron with visible streaks, as I am showing on screen. Since the material is applied to the entire surface, it will also add its Normal and Height effects to the handle area.
In this example the consequences are not too severe, but trust me, they can become much more obvious with different materials. On screen I am showing an example using Diamond Bicolor Tiles, a material I downloaded from Substance Source.
So, how do we solve this problem?
Well, the answer is obvious: by limiting the effect of the material using a mask.
This time, however, we will proceed in reverse. Since the entire object except for the handle should be metal, right-click the Iron Brushed material in Layers and this time choose “Add White Mask”. This creates a white mask covering the entire object. Then choose Polygon Fill with UV Chunk Fill mode, but this time set Color to black, value 0, and click on a point of the handle. In this way, the mask will become black only on the UV island corresponding to the handle, excluding it from the effects of “Iron Brushed”.
To summarize, we have seen how to apply a couple of Substance materials to different parts of a single Texture Set using masks to define the influence areas of each material. We also explored some entries in the Properties - Fill panel for the two materials, becoming familiar with the basic parameters and settings.
That's all for this tutorial. As always, feel free to leave doubts, questions, or requests for clarification in the comments section of the Youtube video. See you next time!