Work continues on the Prisoner of Azkaban version of the castle. My tentative plan at this point is to more or less finish this iteration before fully jumping to any of the other films…but I’ve been known to jump around, so who knows.
The latest structure to take shape is one that other Potter fans seem to refer to as the Defense Against the Dark Arts tower. Apparently the video games place the DADA classroom in this tower, so the community rolled with it. Anyway, this was first seen in Sorcerer’s Stone, and it stuck around through Order of the Phoenix,with a slight relocation from Azkaban onward. (After that, it was replaced by the Astronomy tower, which is basically just a taller and more extravagant repurposing/redesign of the DADA tower.)
There he is, just to the left of the Dark Tower. Basic shape starting to form.
As I continued to work on the top part of the tower, I realized that the DADA->Astronomy transformation (transfiguration?) actually “revealed” some parts of the DADA tower that weren’t visible before. Presumably, these were designed specifically for Astronomy, but I figured it’d be more efficient for me to just create them from the start and conceal them with the remaining DADA structures; then they’ll be ready to go when it comes time to do Half-Blood Prince. Below you can see the Astronomy-ish version on the left, and then on the right we see one of the turrets that conceal some of the geometry on the DADA version.
Then I started adding a few more details on the top part of the tower, resulting in the following render:
…which I liked, but I was starting to get fed up with my plain blue placeholder for the lake surface below. I knew I didn’t want to spend time creating (and rendering) full-on water shaders, but I thought it would at least be cool to try to create some atmospheric perspective (mist) along the horizon. In the process of working that out, I started running into some ways to break up the surface of the water a bit, too, and I couldn’t help myself. Soon enough…
That felt like a good step in the right direction, but it wasn’t enough. I kept going and eventually ended up with this shot, which I gotta admit, I really like.
The reflective water shader has some procedural variation in the roughness to simulate areas with more or less wind. There aren’t any actual waves, though…if I ever decide I need to get in close, it’ll need more work. Then there’s some volumetric fog along the horizon. (It’s literally just a huge torus with some cloudy volumetric shaders on it; I distorted it and put it way out in the distance to help blend the edges of the water with the HDRI background.) I love how my fog blends right in with the photographic clouds just above, particularly from this angle.
Now I was in full-on texturing mode. If I were a wiser man, I’d save all this for after I finish modeling…but where’s the fun in that? I decided I wanted to start experimenting with textures for the castle itself, too. And I decided I wanted to go all procedural.
I mentioned that word before, “procedural.” I’m inevitably going to use more CGI lingo in these posts than I have time to explain for those of you who don’t do 3D art, but this one is worth delving into for just a sec. Basically, anytime you apply a texture to a computer-generated object, the two most common ways to do it are to apply images to the surface or to work procedurally. A procedural texture is one that doesn’t involve any images – instead, you’re telling the computer how to mathematically generate the imagery based on the surfaces it encounters. There are many pros and cons to each, and they each have a lot of uses. One of the pros to going procedural is that if you set it up right, it’ll conform to stuff you build in the future, too. And of course, I still have a lot to build.
Anyway, bottom line, I’m trying to completely avoid using pixel-based images in this main castle texture. After fiddling with dozens of nodes, I came up with this:
We’re starting to get there. It’s beginning to have that stony, bricky, castley look. These color patterns were starting to work for me, but the nodes weren’t behaving quite the way I expected with regards to the way light reflects off the surface (specular, roughness, and normals). I found the problem, did more tweaking, and arrived at this improved version:
The difference is fairly subtle, but to my eye, this looks a lot more realistic and lot more accurate to the films. (Of course, getting a single texture that fits the look of all the films would be impossible, since the color grading changed so much after the first couple of films, making everything kind of greenish-gray. I’m trying to just match the physical miniature as best I can.)
Still, this is very much a work in progress, and it probably won’t be too long before I turn the textures off and just focus on modeling some more.
Hogwarts 4D 
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