Finishing the COS Whomping Willow

Before we get into today’s post, I was asked to share a plan view of the original quad in my model, so…voila! Can’t make any guarantee of its absolute accuracy, but it should be close. (Still missing the terrace along the north side…I don’t have any good references for that.)

Anyway, in our last installment, I’d finished a rough sculpt of the Chamber of Secrets Whomping Willow’s trunk, roots, and major branches. But I decided it would be better to let Blender grow the newer, denser growth on top. I created a particle system to generate paths leading away from the tree’s knuckles. Negative gravity pulled those paths upward to create the right shape. Here’s an early attempt:

After adjusting the parameters some more:

It was at this point that I spontaneously made a work-in-progress video tour of the SS castle, which then morphed into a tour of the COS castle too. This has been up on YouTube for a bit but I’ll include it here in case you’re crazy enough to not have already subscribed there.

But anyway, back to the Whomping Willow. The next step was to add smaller twigs. I created a handful of different shapes and used another particle system to distribute them over the shoots on top. To keep the distribution from being unnaturally even, I painted a “weight map” to control the density. Looks kinda cool on its own:

But of course, the point isn’t to have the weight map look pretty. The point is to get the twigs in place:

Then I went back to the trunk and main branches to sculpt the final levels of detail, giving them a texture that hopefully resembles tree bark. This took a while. Lots of virtual scraping with my Wacom tablet. (For fellow Blender users – I did most of my rough sculpting with the wonderful Clay Strips brush, and then I adjusted the falloff of the Scrape brush to dig all the grooves into the bark.) In the next render, you can also see me starting to experimenting with procedural normal maps to add another level of detail:

Then it was just a matter of refining the coloration of the tree and texturing the rocks at the base!

That flat lawn texture doesn’t look horrible from a distance, but it’s pretty obvious that there’s no actual grass here when you get close like this. So I did something I’ve been meaning to do for a while: I used Blender’s relatively new geometry nodes feature to create actual blades of grass.

This was my first foray into geometry nodes. Initially, I just wanted to add blades where the lawn approached other objects (like the Willow). That way I could at least get rid of the hard edges but still keep my computer from blowing a gasket. But the performance seems to be better than with the existing particle tools, which is really exciting. I’d been worried about how to tackle the surrounding landscape if my computer couldn’t handle that many blades of grass, but this has me more optimistic. I went ahead and just covered the whole lawn with actual blades, and it seems to be working fine!

Anyway, here are some views of the complete COS Whomping Willow!

More updates to come!

Starting the Whomping Willow (COS Version)

Let’s recreate the original Whomping Willow! It was added to the training grounds in COS. That location – and even the tree’s very presence in the miniature – is unique to to that film. (In all the later films, the redesigned Whomping Willow was off the edge of the map, somewhere past Hagrid’s, and it was brought to life purely through CG and full-scale practical elements.)

The first step was to figure out the exact placement. I don’t have any floor plans that show precisely where it sat in relation to the other structures, but one of the behind-the-scenes features does give a decent shot of that area of the miniature. I lined up the camera angles and added a circle to mark the base of the tree. It seems to be just about dead center in that lawn! This further reinforces my belief that this area’s walls were redesigned for the express purpose of giving the Willow a more interesting setting. They almost create a kind of arena around it.

Next up: creating a base mesh. I knew I wasn’t going to be able to match the tree in the film perfectly, but I wanted to capture its essential rhythms, character, and scale. I ended up annotating film screenshots with color-coded numbers to help me keep track of the different major branches. It’s a strategy that served me well with the grand staircase model.

I carried that color coding into the model itself as I started the base mesh. As with the tree in the clock tower courtyard, I decided to use the Skin modifier in Blender. This lets you quickly extrude chains of vertices and apply a basic radius parameter to each, creating blocky forms that become tubular with the Subdivision Surface modifier. Here are a couple of work-in-progress shots:

As you can see, the base mesh is SUPER photorealistic. Can’t even tell it’s not a real tree! …right? (My girlfriend says it looks like a piece of corporate modern art, and I don’t disagree.)

Don’t worry, things started to get a little better as I Boolean-ed all the branches into one object and began the sculpting process.

There appear to be some stony areas at the base. I experimented with sculpting them all as one mass. When that didn’t look right, I tried using physics simulation to “drop” all the stones on top of each other in a realistic pile. But sometimes simplest is best, and in the end, it was most expedient to separately sculpt each rock and lay them on top of each other manually. Another pass of Skinned tubes allowed me to start blocking in the tree’s tangled roots:

Obviously very rough; the idea is just to build some geometry that will take well to further sculpting. And while I admit I wasn’t SUPER excited about this switch from hard surface to organic modeling, I soon found myself enjoying the sculpting process once more. It’s gratifying to see these basic shapes start to look like something!

This was around when I realized my proportions were a little off. The main trunk needed to be a little bigger relative to all the branches. I made some adjustments and kept sculpting, working my way up into the knuckles and knobs where all the younger shoots will soon go:

None of this is an absolutely perfect match with the film, but I’m certainly trying to stay close. That crevice on the left side of the trunk is based on one visible in the film; in my headcanon, that’s where the tunnel to the Shrieking Shack is. (We only see the entrance to the tunnel in the next film, and the Willow was redesigned for that one.)

By the way, in case it’s not obvious, I haven’t started texturing the tree or the rocks yet. The flat coloration is just temporary while I continue refining the forms. I’ll save all that for the next post, as well as the addition of all the shoots on top that’ll really give the tree its characteristic look. But I think we’re off to a good start!

Roof Flashing, Version Mashing, & Quad Teeth-Gnashing

The next thing to add was roof flashing. It’s been on my to-do list for ages. (Not sure why I haven’t just been adding it as I go…) It’s not very glamorous work – no one looks at a render and goes, “Oooh, look at that beautiful roof flashing!” – but the model just doesn’t look quite right without it. Here’s what I’m talking about, as I started to add it:

There are ways of doing this kind of thing automatically, but I wanted it to look a little imperfect, so I used Blender’s “Snap to Face” functionality and drew it all in manually.

Here are the SS and POA models with all the flashing added:

(If you want to see the flashing itself, I’d recommend right-clicking to open the images in new tabs so you can view the full resolution.)

It feels like time to work on the COS version of the castle, doesn’t it? In almost every way, it’s just an intermediate step between SS and POA, so I figured it shouldn’t be too hard. Everything south of the ravine is identical to SS, although the real miniature did receive some touchups. It’s the north side that changes.

After mashing together the appropriate elements from the SS and POA castles, I proceeded to create the new training grounds, with their relatively flat lawns that existed only in this film:

I really like this version of the castle. Here’s the above render’s isolated mist pass, too, just because it looks cool:

But there’s one major element missing: the Whomping Willow! That’ll likely be the topic of my next post.

By the way, the original quad continues to vex. Deeply. I’ve really been enjoying the discussions in the comments about the cloister. It’s led me to a very divisive debate (in my own head) about whether its design owes more to Gloucester Cathedral or Lacock Abbey. I was pretty confident in the answer being Gloucester…but now I’m really profoundly split.

Reasons to think it’s Gloucester:

The whole courtyard is labeled “Gloucester” in the later films’ floor plans (after the removal of the cloister in question).
The quad building has Gloucester-style windows on south outer façade, and they almost had them at the same level on the west façade as well. All of these are around the same level as the cloister.
The paths and fountain aren’t an exact match to any location I’ve found, but they’re a lot closer to Gloucester than to Lacock.
The Lacock courtyard is never really seen in the films; the Gloucester courtyard is, if only very briefly.

Reasons to think it’s Lacock:

I thought all the films’ floor plans labeled the courtyard “Gloucester,” but I realized that what I’m reading on the early plans is just the word “cloisters.”
There’s a floor plan from the first film that shows the way some sets and real-world locations fit together in the filmmakers’ imaginations. It is substantially different from the layout of the miniature, but the Lacock Abbey courtyard and cloister are placed right next to the grand staircase.
From the overhead shot in COS, it looks like the cloister is rather tall, with a blank stretch of wall above the tracery. Lacock’s cloister has a similar design; Gloucester’s doesn’t.
Lacock is a closer match to the size of the quad.

Soooooo…yeah, I’m pretty split. For now, I’ve added the blank bit of wall and raised the cloister roof accordingly, but I haven’t changed the tracery to match Lacock. I’m waiting till I (hopefully) find some more reference material.

Anyway, be sure to “follow” so you can be notified when I post the Whomping Willow!

Starting the Training Grounds Curtain Walls (POA Version)

Yikes…it’s been a long time since my last update! Sorry about that, folks. One of the many factors: the training grounds tower is tough! It’s hard to find enough reference images. So to give myself a break, I switched gears to focus on the castle walls.

The curtain walls and small towers surrounding the training grounds were originally derived from those at Alnwick Castle. A large swath was then redesigned in the second film, probably to add visual interest in the Whomping Willow scenes. The westernmost areas (near the first flying lesson) still stayed the same until the third film, when they were swallowed up by hilly terrain. In effect, only the COS redesign remained. That’s the state the miniature is still in now, although the CG version in Deathly Hallows and Fantastic Beasts omits the walls altogether.

I started at the western end of the COS revisions:

This illustrates some of the challenges in mapping the stone brick textures correctly to the model when the angles get funky. I’ve tried to create a material that just behaves correctly no matter what I build, but sometimes I need to get in there and manually fiddle with the mapping to get it right.

These structures all look strangely tall right now, but eventually the terrain will cover up most of the lower areas:

They’re also in pristine condition compared to their appearance in the films, since significant chunks of the above-ground areas have crumbled away. But it’s always easier to create the full “original” structure and then weather away the parts you don’t need.

Here’s the same view with some more adjustments, details, and additions, but still no weathering:

And now, swinging around the easternmost area, we link it all up with the areas that are directly taken from Alnwick Castle:

I’ve also fixed the mapping of the brick textures here:

Some of these areas don’t quite match between the blueprints, the photogrammetry of the miniature from the Studio Tour, and the real-life correlates at Alnwick. I’ve aimed for a happy medium that tends to favor the actual miniature.

Then and only then do we get to the weathering, by way of a Boolean modifier. If you don’t know what that is…well, imagine carefully shaping a floating glob of poisonous molten radioactive alien laser acid that will eat away any part of the wall it touches. Actually, you know what? I won’t make you imagine it – here are my Boolean acid globs:

And yes, the glowing lava look is a critical part of getting the Boolean modifier to work right. TOTALLY necessary. 100%. Anyway, move the above slider back and forth to wipe away the glowing poisonous molten radioactive alien laser acid lava and reveal the weathered stone beneath.

I’ve still got to built the western half of the curtain walls, the parts that weren’t changed from their Alnwick-like state. But I’ll save those for a future post so I can at least have something to share with you now!