SoftBody¶
Soft bodies (or soft-body dynamics) simulate movement, changing shape and other physical properties of deformable objects. This can for example be used to simulate cloth or to create more realistic characters.
Basic set-up¶
A SoftBody node is used for soft body simulations.
We will create a bouncy cube to demonstrate the setup of a soft body.
Create a new scene with a Spatial
node as root. Then, create a Softbody
node. Add a CubeMesh
in the mesh
property of the node in the inspector and increase the subdivision of the mesh for simulation.
![../../_images/softbody_cube.png](../../_images/softbody_cube.png)
Set the parameters to obtain the type of soft body you aim for. Try to keep the Simulation Precision
above 5, otherwise, the soft body may collapse.
![../../_images/softbody_cube_menu.png](../../_images/softbody_cube_menu.png)
Note
Handle some parameters with care, as some value can lead to strange results. For example, if the shape is not completely closed and you set pressure to more than 0, the softbody will fly around like a plastic bag under strong wind.
Play the scene to view the simulation.
Tip
To improve the simulation’s result, increase the Simulation Precision
, this will give significant improvement at the cost of performance.
Cloak simulation¶
Let’s make a cloak in the Platformer3D demo.
Note
You can download the Platformer3D demo on GitHub <https://github.com/godotengine/godot-demo-projects/tree/master/3d/platformer> or the Asset Library.
Open the Player
scene, add a SoftBody
node and assign a PlaneMesh
to it.
Open the PlaneMesh
properties and set the size(x: 0.5 y: 1) then set Subdivide Width
and Subdivide Depth
to 5. Adjust the SoftBody
’s position. You should end up with something like this:
![../../_images/softbody_cloak_subdivide.png](../../_images/softbody_cloak_subdivide.png)
Tip
Subdivision generates a more tessellated mesh for better simulations.
Add a BoneAttachment node under the skeleton node and select the Neck bone to attach the cloak to the character skeleton.
Note
BoneAttachment
node is to attach objects to a bone of a armature. The attached object will follow the bone’s movement, weapon of a character can be attached this way.
![../../_images/softbody_cloak_bone_attach.png](../../_images/softbody_cloak_bone_attach.png)
To create pinned joints, select the upper vertices in the SoftBody
node:
![../../_images/softbody_cloak_pinned.png](../../_images/softbody_cloak_pinned.png)
The pinned joints can be find in SoftBody
’s Attachments
property, choose the BoneAttachment
as the SpatialAttachment
for each pinned joints, the pinned joints are now attached to the neck.
![../../_images/softbody_cloak_pinned_attach.png](../../_images/softbody_cloak_pinned_attach.png)
Last step is to avoid clipping by adding the Kinematic Body Player to Parent Collision Ignore
of the SoftBody
.
![../../_images/softbody_cloak_ignore.png](../../_images/softbody_cloak_ignore.png)
Play the scene and the cloak should simulate correctly.
![../../_images/softbody_cloak_finish.png](../../_images/softbody_cloak_finish.png)
This covers the basic settings of softbody, experiment with the parameters to achieve the effect you are aiming for when making your game.