This setup shows you how to destroy a fractured wall with a wrecking ball. A sphere falls down and crashes into the wall, and destroys it. A MultiJoint constraints the sphere to the mounting and acts like a rope.
The scene setup with the wrecking ball, a prefractured wall, and MultiJoints.
Here is the nodes list:
- 2 “Sphere” objects (wrecking ball, steering geometry)
- 3 “Cube” objects (wall, mounting, ground)
- 1 “Null” object (locator)
- 1 “Gravity” daemon
- 2 “MultiJoint” nodes
All scene elements can be added from RealFlow's “Edit” menu:
- Add > Objects | Daemons
RealFlow nodes can be moved, scaled, and rotated with the W, R, and E keys.
Imported objects from SD files have to be unlocked before they can be transformed with Selected object > Node Params > Node > SD ↔ Curve
Viewport perspective is changed with the 1, 2, 3, and 4 keys.
Shading modes are toggled with the 7, 8, 9, and 0 keys.
Add a cube object and rescale/position it to your needs. This node (“Cube01”) will serve as the wall.
Create another cube (“Cube02”, the mounting) and place it somewhere above the wall.
The third cube (“Cube03”) is the ground node
A sphere is used as the wrecking ball (“Sphere01”) and positioned next to the mounting.
A null (“Null01”) )is placed directly below the mounting.
“Gravity” introduces a force.
All polygon objects are passive rigid bodies, except the sphere (active rigid body):
- Selected node > Node Params > Node > Dynamics
Now, add a MultiJoint and open its “Creation” panel under “Node Params”:
Objects A > Sphere01
Objects B > Cube02
Creation mode > At Locators Positions
Locators > Null01
Determining the Zone of Impact
Simulate the scene. If the sphere does not hit the wall, reposition the wrecking ball rig and/or change the distance between the sphere and the mounting.
When everything is adjusted correctly, go back to the frame where the sphere hits the wall and place another sphere (“Sphere02”) inside the wall node. Make it slightly bigger than the wrecking ball.
Create the Fractured Wall
Select the wall node (“Cube02”).
Open the “Voronoi by Steering Geometry” tool from the “Tool Bar”.
Enter the values as shown below and click on “OK”.
Delete the “Sphere02” and “Cube02” objects – they are not needed any longer.
Change the new object's “Dynamics” mode to “Active rigid body”.
Reconnect the Wall's Fragments
Right now, the fragments will start to break apart when you start the “Simulation”. Therefore, you have to reconnect them:
Add another MultiJoint node (“MultiJoint02”).
Open the MultiJoint's “Creation” panel under “Node Params”.
Objects A > Cube03, Cube01_fractured01
Objects B > Cube03, Cube01_fractured01
Forces > Force max mode > Constant limit
@ Max force > 150000
Collisions > Enable if break > Yes
Break > Break if distance exceeded > Yes
Click on “Simulate” to see the results. Play with different “@ Max force” settings of the “MultiJoint02” node to get different degrees of destruction.