Creating more Materials
Following on from last week I decided that the following week I would focus on texturing the everything within the scene at the moment. And this requires me to create more materials in Substance Designer. I'm not budgeted for the amount of textures I use, so I'm using however many I need to get the scene to look great. Something that somewhat frustrates me is the amount of different types of wood I have to create. Creating foliage was a nice break from all of the wood textures, but this week I'm getting back into it.
The first thing that I wanted to texture, was the tree. As the birch tree is somewhat of a centre piece and is a focal point of the scene showing how the house is in shambles. It also serves as a starting point for all of the foliage and greenery to be growing in the room.
I followed a tutorial to create this however there were many parts that I had to improvise, as the tutorial used some of their own pre-made textures and nodes. Two parts that I created was the Underwood and the cracks on the knots.
For the windows of my scene, I was wanting to take some inspiration from the windows currently in my bedroom. A lot of the traditional Izba's have just a wooden window. But I've found some that also have a layer of paint that strips as well.
After creating the Birch texture I was able to use a lot of the techniques and processes that I learned from that again for this. As there is essentially two layers of a different material. A rough and textured wood with a smoother dirty paint coated on top.
Something that I really wanted to come across is the feeling of that the paint will peel off easily. And this comes from the bumpier parts of the paint that look as if its coming off the wood.
With this material I really wanted to make sure that the texture is not incredibly noisy. Which is why I limited some of the larger peeled parts of the wood to be mainly in a small vertical slice. With smaller cracks appearing here and there.
Below is what the wood looks like underneath. I didn't want to have the wood that you see in the cracks to be all the same, so there is a slight variation. I also did not spend too much time on the wood as most of it is covered.
The next thing I worked on was to create a Terracotta Clay. There are a lot of pots and jars in the scene and since the clay is different to what's on top of the stove, I thought it would be better to make it its own material. I think this material may need some more tweaking down the line as it is very saturated red colour. I may need to also have multiple normal textures to give a sense of variation within the scene.
Another repeating material within the scene is cast iron, as there are many cooking tools made out of cast iron. The texture might look quite bright in Substance Designer, but from my own experience metallic materials will always look darker in Unreal Engine than it is in Substance. If it appears to be bright within Unreal I can always tweak the base colour within the instance material.
The last material I was able to finish in the second week was a moss material. I followed a tutorial by Tim Simpson, however once again there were many parts that I had to improvise. The tutorial gave me a direction but didn't lead me through the process every step. I enjoy this way of learning much more, as I remember things better when I have to problem solve.
I will need to come back to this material as its mainly a base. I need to add smaller details such as these flowers that I found in my references. I also need to make a mask for creating small clusters instead of the moss covering the whole surface.
Applying the Materials in Engine
To get these materials the way I want to look and to add more interest I added some more nodes to the Master Material.
The first addition being a manipulation to the texture uv's, and offsetting them based on the object position.
The second addition is basically a set of parameters that allow more customization of the base colour. Which mainly work on materials that aren't metallic as the blue channel will instead have a mask.
Above you can see the first addition. Its fairly simple and slots in just before the other effects such as custom rotation and tiling. I've also added it into the graph with a lerp so that it can be switched on and off.
The nodes are fairly simple, using an object position node which is the position of the object the material is applied to. I masked out the x and y from the position so that I can have more variety. If two objects are on the same x coordinates moving one model by just the y coordinates will make it differ.
Something strange about this set up is that it only works if you move objects with movement snapping turned off. However it still works with rotation snapping on. I have no idea why this is and I'm sure I can find a solution, but at the moment it works for what I need.
I also want to point out that this is different to world aligned texture, as world aligned texture projects the texture onto an object based on the x y or z coordinates. Anything that is in between those coordinates often have stretched UV's. What my version does changes the UV position of the textures depending on the object position. This isn't projecting the textures onto the object, but just moving the UV's on the already unwrapped object to make it look slightly different.
This section is all about getting more colour variation without adding much and making the most out of the existing textures I have.
As mentioned before but this works best for materials that aren't metallic at all or are fully metallic, as this uses what would be an underutilized blue texture channel of the RGBA. It would be best if it was a mask of some kind.
Quickly running through, I multiply "Colour A" with the red channel of the RGBA which would be ambient occlusion. This helps to add more value to an otherwise solid colour. After that I introduce "Colour B" this is an additional colour which can be of a different hue or saturation. This "Colour B" uses the roughness as a mask to add the colour on top of Colour A. This roughness mask can be adjusted with some scalar parameters I put in place.
This is all then added back on top of the original base colour texture using the blue channel as a mask of where the colours will override the base color texture.
Additionally to the colour change, I've added the functions of changing the normal intensity and roughness based on the mask. This allows me to have more variation and works well for a material such as Terracotta clay which would sometimes be half glazed. And the glaze would have a smooth reflective surface.
The above image is what the textures look like before the colour changes.
And this is what the textures look like with the colour changes. In the gif I am changing parameters related to "Colour B", controlling how much the colour spreads and changing the hue and saturation.
To finish off this blog post I want to show pictures of the progress in the different rooms. There are somethings that I haven't gone over such as that I've unwrapped and edited a bunch of models, but this is just so that I can apply the materials I've created. I did however change the lighting after getting critique from one of the tutors, so the scene is much darker and more similar to that of the concept art.
Next week I'm hoping to finish the master wood material that I started at the end of week 14. Add moss to the floors and object, spread out and place foliage. And create the last two foliage pieces.
