🔴Learn about cloth effects in 3D modeling and how to use them effectively.
Explore cloth simulations, passive collider presets, and various settings like friction and stickiness.
🔴Create realistic cloth animations, curtains with wind effects, and tearing cloth effects using spheres.
🔴Additionally, discover how to simulate pillows using pressure settings. Master the art of cloth simulations to enhance your 3D modeling projects.
- Workflow
The first thing we want to do for today’s class is switch from Modeling mode to FX mode so that we have access to the visual effects options inside our workspace.
We’ll mostly focus on the nCloth tab and see what the first two options let us make in our project.
Another big note to keep in mind is to not delete the history when working with simulations because it will remove it completely from the objects you’ve added the simulation to.
In the workspace add two planes and change the topology on one of them to have 40x40 subdivisions.
We will need this to run an experiment to see how a low and high poly will react to the cloth simulation we’re going to make.
Underneath the planes make a quick table out of any object of your desire, we’ll be using a cylinder and extruding it to make it resemble a table, but any surface will do just make sure the surface is smaller than the surface of the plane covers to have a better cloth simulation.
To add cloth simulation onto the planes, select both of them and click on Create nCloth in the nCloth tab.
To activate the cloth simulation press on the play button next to the animation timeline below the viewport.
When we do, the simulation will activate and the planes will start falling downward but go through the table.
This is because we haven’t set a collider on our table and the simulation isn’t registering the cylinder as a surface for the cloth to fall on.
To fix this, select the table and click on the Create Passive Collider inside the nCloth tab.
Now that everything is set up we can run the simulation again.
Hide the plane with the higher polycount so that we can see how the low poly plane will react to the simulation.
When we press play on the time line the cloth will fall down on the table and begin to bend.
Though because the plane is so low poly it won’t bend a lot.
If we run the same simulation but this time with how the high poly plane will react, we can see that the folds are going to be more extreme and overall better.
Another issue we can see is that because we don’t have enough frames on our timeline we won’t be able to see the full extent of the simulation and will stop mid-bend.
To fix this issue simply add more frames on the timeline and let the simulation play out again.
If we want our plane to stay bent like a cloth we need to duplicate it from a frame we like.
Run the simulation again and stop it when the cloth is fully bent.
Then click on the plane and duplicate it with Shift + D.
Now the plane will forever stay like that and the timeline won’t affect the duplicate and only the original.
In our Otliner we can see a few new things added in when we added the nCloth simulations and collider.
The nucleus is the gravity that affects the cloth.
We can change the gravity settings inside the Attribute Editor.
We’ll look at the settings later in this class.
The nRigid is the surface of the collider.
Inside the Attribute Editor, we can see the nRigidShape which is the settings for the collider.
It affects the texture of the surface like Friction, Bounce, Stickiness, and many more things that will give us an interesting simulation.
For example, we will make a small movement animation on our table.
Choose a frame where the cloth just made an impact with the table, add a frame while having the table selected, then go to 30-40 frames forward and move the table, adding a keyframe afterward.
Now when we play the animation we can see the simulation working as normal and when the table moves the cloth reacts accordingly and slips off the table.
This is because of the Friction.
If we change the friction to a bigger value and then play the same animation, the cloth will stick to the table instead of falling off.
We have the same settings inside the nCloth inside our outline but this is for how the cloth behaves rather than the surface.
Inside these settings, there are more complicated and interesting changes we can add to the cloth.
There are also preset settings that save us the time to create specific simulations like chainmail, an airbag, lava, honey, etc.
On the side, we have options if we want to fully replace the current cloth simulation or blend it with the existing one.
For now, we will fully replace our nCloth with chainmail and see how the simulation looks.
Be sure to wait for the red bar on the timeline to fully load before pressing play so the simulation can fully be loaded in.
When we press play now we can see the cloth feels heavier but it also doesn’t slip off right away instead it takes longer to fall off and the impacts are heavier.
The reason why the chainmail preset looks so sturdy is because of its Mass.
If we change to the SIlk preset the mass will be much less than the chainmail.
Another interesting preset for the nCloth is the honey preset.
When we add it onto the cloth and play the simulation it will start to run down and drip and continuously stretch out the cloths just like honey would.
We’ll make a new scene by using the Ctrl + N shortcut to move forward to our next exercise.
Insert a cube inside the new scene and turn it into a window frame by stretching and squishing it to get the shape, extruding the faces inward from both sides, deleting them, and then brushing the edges to close up any holes.
Next, add in a cylinder to create the curtain holder but also it is going to help us make the cloth simulation for the curtains.
We want to cylinder to be really long like in the image below.
Add a plane for the curtain and scale it to fit the exact length of the cylinder.
Change the plane subdivisions to 70x50, we want to have more edges running down vertically to help us create the curtain simulation.
Hold V when moving the plane from the side so that you can snap it perfectly below the cylinder, this is an important step, make sure you have the geometry grid enabled so you can snap the plane to the edges of the cylinder.
Another important thing is to leave a nice small distance between the cylinder and the plane.
Select the plane and Create a nCloth.
Select the window frame and the cylinder and Create a Passive Collider.
From the front view select the first row of vertices from the plane.
While the vertices are still selected hold down Shift and click on the cylinder to select the object.
Now that both the plane vertices and the cylinder is selected, click the nConstraint tab and select the Point to Surface option.
Once we do this we can see that there are green lines connecting the vertices to the cylinder.
From here when we play the animation we can notice the nCloth affecting the plain because it slightly bounces as the timeline is going through the frames but the plane doesn’t fold up.
This is where the cylinder comes into play.
Add more frames to the timeline.
Select the cylinder and go to the 15th frame and add a keyframe by clicking S.
Move to the 40th frame, scale down the length of the cylinder to fit the window frame, and add another keyframe.
Now when we play the animation the cloth folds up to form a curtain.
We can add wind effects in the nucleus settings by changing the Gravity and Wind values.
If we change the Gravity Y direction from -1 to 1 the curtains will go up when we play the simulation.
The Wind Speed changes how fast the wind will blow through the cloth and the Wind Direction is for the direction from which the wind blows.
Giving the Wind Speed a value of 15 will have a drastic impact on the cloth.
The Air Density is how dense the wind is.
Changing the Wind speed to 6 and the wind direction to -1 will make the wind enter from inside and blow the curtains outside of the window frame.
For the next exercise create a new scene with Ctrl + N and add a cube to the scene.
Scale it in length and duplicate it to the other side.
In the middle add a plane with a subdivision count of 12x12.
Select the plane and create a nCloth for it and afterward select the squares to create a Passive Collider.
Just like we did with the window curtains from the front view select all the vertices on the left side then Shift + select the left square, go into the nConstraint tab, and click on the Point to Surface option.
Repeat the same thing on the right-side vertices.
Now we have the plane attached to the squares on each side.
If we play the simulation now the plane will just hang from the two squares and nothing much will happen.
Add a sphere in the scene, placing it in front of the cloth.
On the 15th frame add a keyframe for the sphere.
Go to the 50th frame, move the sphere to the other side of the plane, and add another keyframe.
Select the sphere and also give it a Passive Collider.
When we play the simulation we can see that the sphere is stretching out the cloth but it isn’t tearing it.
To make the cloth tear during the simulation, select the plane, go to the nConstraint tab, and click on the Tearable Surface option.
Now when we play the simulation the cloth will tear when the sphere goes through it.
For our final exercise, we will create a pillow.
Make a new scene with Ctrl +N.
Add a cube and shape it into the basic form of a pillow.
Change the Subdivision Width to 100, Subdivision Height to 2 and the Subdivision Depth to 100 to add extra topology so that the simulation works properly.
The more topology something has the better the simulation will work.
Select the cube and create a nCloth.
In the nCloth setting, we have the Pressure tab.
If we change the pressure value to 0.025 and play the simulation we can see the cube forming into a pillow but it begins to fall in the world.
To prevent it from falling in the Gravity setting inside the nucleus, change the Gravity to 0.
When you play the simulation again the pillow won’t fall.
If you don’t want the pillow to be so big you can change the pressure to have a lower value something to 0.005.
Now when you play the simulation the pillow won’t puff up so much.
When you are satisfied with the look of the pillow you can select all the edges and Soften them.