Author: Yuanhang Wu

Build the scene

The inspiration for the scene came from the scenery outside my friend’s apartment.

These giant cranes have a different kind of beauty.

These giant cranes have a different kind of beauty. I imagined in my mind a lot of birds flying around skyscrapers and cranes. Perfect!

But time certainly won’t allow me to model cities from scratch. But I was lucky enough to find an old collection: a set of city models.

I chose three sets of buildings similar to those in the photo and combined them in the new scene.

But just putting the three buildings together was not enough, I also modeled the road myself to make the scene look more realistic. Other city props like street lights, traffic lights, fences, fire hydrants, etc. are from one of my previous C4D projects.

Now the crane is still missing.

But luckily I found a crane model shared by others on a solid work forum. I am so grateful!

But this crane is static. This could be a problem, so I separated out the parts where the crane might move.

The reason I put them this way is that I will be combining them in Houdini, so I need them all in the default positions.

ok I will combine them in houdini next week.

It took me almost 4 days to animate these five stages. I learned a few things during the animation of birds:

1 Bird animations are distinguished from other animals’ animations by the point that a bird’s head is static compared to its body.

2 After practice, separating the wings, claws, and bird heads is better when keyframing birds.

3 And I used a tag to name the content of each keyframe; for example, the first red keyframe is the flying loop.

Here I skip the jumping stage because it seems that this stage is not used.

At this point, I have basically completed the animation of the pigeon. But here the is in place animation. In other words, the pigeon does not move.

So here I parented the two Ik of the pigeons to a locator. This makes it possible to move the pigeon by moving the locator. The next step is to add keyframes to the locator.

We have basically worked out the generation of a crowd now. The next thing to do is replace the animation of the human walking with the animation of the pigeon.

Then let’s finish the animation of the pigeon first.

The first is the pigeon model. Due to time issues, there is no way to model and bind it yourself. But luckily, I found a very suitable pigeon model on the forum.

The model rig for this pigeon is very detailed, and the bones are constrained with IK. Not only that, but every feather was carefully modelled.

I’m going to start animating it next. But before I start, I want to export the references as sequence frames so I can import them into Maya.

This is the reference import method that Alan taught in the first semester.

This week will mainly study crowd animation in Houdini.

I watched a series of tutorials on crowd animation in Houdini on youtube. But all of them are human. None of them has a single animal.

But the following tutorials are still helping me get started.

This first video talks about how to set up an agent. The agent is the unit that makes up the crowd. Simply put, it is one person in a crowd.

These two nodes help set up the agent.

The function of this node is to read the FBX animation file on the hard disk and convert the animation into an in-place animation centred on the character’s hips. Remember to name the animation clips here, because you need to retrieve and call the clips by the name of the clips later.

The next node allows me to add more clips to the agent, like running and walking.

At this point, the set-up of the agent has been simply completed.

The next video shows how to generate crowds and randomize their state.

The nodes used in this video are a bit more complex.

This first node called crowdsource has two inputs: Agent meshes on the left and points for agents’ position on the right.

The next node is dopnet, in which we can keep working on the crowd system.

The node crowdsolver is the key node in this crowd system, which means it does the most of work. It can be seen from the fact that it has four inputs. The first input passed in is the agent. And the third input passed in is the agent stages, which are the clips we reloaded as FBX.

Finally, we can randomize the time offset of each agent in the crowdsolver node to make them walk differently.

This video is about how to use a curve to guide the direction of the crowd.

The node popsteerpath can help do the job. This node is very important and I will use it a lot in my project in the future.

This video tells how to render the crowd in Houdini.

I spent a day in the park this Tuesday recording pigeon flight footage for reference.

At that time, a lot of material was shot, and it took a lot of time to sort out the useful clips in these materials. But in the end, I managed to sort out the above video materials.

The full video collection can be accessed at this link:

飞禽动画素材（多P）_哔哩哔哩_bilibili

According to these materials, I divided the pigeon flight and landing into 5 stages: Fly, Sub Altitude, Jump, Run and Walk.

Although not all of these stages will be used, after several days of observation and analysis. I have become more familiar with the dynamics of birds, and it can be said that I have learned a lot.

After more than a week of research, I think this project has good feasibility.

But there is one more difficulty that needs to be resolved before the animation production plan can be made: cluster animation. After all, it’s impossible for me to manually keyframe each pigeon.

Next week I’ll be mainly working on crowd animation.

Inspiration

The first video was taken while I was doing the assignment in the school library in December 2021, while the second video was taken at the crossroads at the school gate the other day.

The pigeons circling like this will never be forgotten in my memory.

The flight of these birds seems to follow a specific pattern, but it also appears that there is no trace.

Why not reproduce them in the virtual world?

I’m a beginner when it comes to editing and dubbing.

But the tense atmosphere of the film is often conveyed by sound.

Just like when playing a horror game and muting it out of fear, it doesn’t feel horrifying if so.

First, I added the sound for the rotation of the treasure so that the humming sound could add a sense of mystery to the treasure.

Next is the sound of footsteps. I cut in the sound of footsteps before the screen changed so as to reflect the feeling of someone approaching.

The choice of footsteps is also worthy of attention. The first is the material of the table mat, which should not be crisp but relatively dull.

Next is the character’s voice. Because the character is not a natural person but a wooden puppet, like Pinocchio, the movement of the character should be the sound of rigid joints rubbing instead of human gasps.

Also, I added tense symphonies and stopped them abruptly at several key plot points to further heighten the tension and create contrast.

The same trick I also applied to the sound effects of gun firing and glass breaking.

The sounds of the guns came from the Call of Duty 14 training ground, and I screen-recorded the game and then captured their audio tracks.

End.

When I try to export the characters as fbx and load them in c4d, I find that there are always missing and deformed meshes.

So I ended up caching the skins as alembic files and not exporting the bones. This saves a lot of hassle, but the downside is that the alembic files are completely uneditable after being imported into c4d, and you can’t even move them.

But luckily, the scene in my Maya is precisely the same as the scene in c4d, so caching as an alembic file is feasible.

After importing the character animation into C4D, add wooden textures to the character.

I am delighted with the effect.

But then I came across one of the most complex parts of the project: Cinematography and narrative.

During this period, I drew for a day and referenced a lot of videos, blogs, and YouTube videos.

These shots are close-up to show the details of the treasure or running details.

I used a Hitchcock zoom here to accentuate the tension.

Here I use a sleepover lens to express the complex inner heart of the character at this time.

Changing the focus from one thing to the other, here I use these tricks to guide the audience’s attention.

Rendering these sequences also took me a lot of time.

I organized the rendered sequence frames with the same naming convention.

Next week is time for clipping and dubbing.

After more than 10 days of continuous work, I finally finished the animation of the entire mirror.

I unpacked some of the storyboards halfway through to reinforce the narrative.

My strict naming conventions have helped tremendously in project management. Because the editor let me know clearly which sub-mirror corresponds to which file. What I do is save a project with no keyframes at all and name it 00 before starting the animation.

I will make a clone of 00 for every additional storyboard that follows. Like 01, 02, 03, etc., on the basis of 00.

The whole animation went very smoothly, just like the basics of animation in my first semester. The entire process is not worth describing.

BUT

I ran into a problem that I couldn’t entirely solve until the end: gun animations.

In this scene, hands A and B’s Ik are parented to the rifle. In this case, hands move when the rifle moves.

But when I key this parent attributes to release constraints to let the hand do other animation like slapping the rifle. The keyframe that slaps the rifle will affect the keys before I release the constraints to break parenting.

My solution was to add moving keyframes to the firearm for the entire firearm animation as a first step. Then bake keyframes for the hands that follow the movement of the gun. Finally, delete some of the baked keyframes you started with and replace them with keyframes slapping the rifle.

But it’s really not a good approach because once I bake the keyframes, it means I can no longer animate the movement of the gun.

The result of my search on google is that the solution of fps game companies is to rig the guns.

But anyway, all the character animation is done.

Animating the characters will start this week!

As we mentioned earlier, this is a toy figure.

So the role model used in the first-semester project is a good fit. And I can even go ahead and use the scripts I developed.

But I need to do the character textured before animating it.

cuz UV will also be keyed when animating it. And I hope this is a wooden villain.

If the UV ratio of each part of the body is not uniform, the size of the wooden texture will also be different. So I used a checkerboard map to check the UV.

Checked UV

The checkerboard texture is available for download.

After checking the UV I can finally start animating the character.

Next comes the very traditional animation. I’ll summarize the problems or tricks I’ve encountered next week.