Cinema 4D / BodyPaint 3D Program Documentation Tutorials MoGraph Tutorial
Function available in CINEMA 4D Broadcast, Studio

MoDynamics: Shatter

Not only can dynamic effects such as collision and attraction be applied to generated clones, they can also be applied to individual parts of a Shatter object. In this tutorial we will hurl several spheres at a ring, which will cause the ring to shatter into pieces.

Click on the link below to open the Cinema 4D starter file:


Preparing the ring

The Cinema 4D file already contains a ring and a red sphere but before MoGraph can be used to shatter the ring it needs to be modified accordingly.

In order to be able to break the ring down into its polygonal parts the Torus object must first be made editable using the Make Editable command (alternatively you can simply select the Torus object and then press the c key on your keyboard). Next, we need to disconnect all polygons so we can let the object shatter into pieces.

To do so, switch to a Selection tool, e.g., the Rectangle Selection, and disable its Only Select Visible Elements option.

Switch to Polygons mode and click+drag the Selection tool over the ring until all polygons are included in the selection.

Next, select Disconnect... command from the Mesh | Commands menu and make sure the Preserver Groups option is disabled before executing the command. Otherwise the selected polygons will not disconnect correctly. This completes the preparation of the ring and we can now turn our attention to the MoGraph effects.

The ring needs to be recognized by MoGraph as a shatter object. This is done by adding a Fracture to the scene from the MoGraph menu and making the Ring object its Child object in the Object Manager. Set the Fracture Object’s Mode to Explode Segments As you have surely noticed, the smooth ring we had at the onset of the project is not so smooth anymore. In order to restore a smooth surface we will reconnect the polygons - but only visually.

To do so we will use the Connect command from the Mesh | Conversion menu. In its Attribute Manager settings, drag the Fracture Object into the Objects field and set the Phong Mode option to Average. Although the ring is again smooth we still need to add a Subdivision Surfaces object. For our example, however, a Cloth Surface cage from the character tools would be better because it handles each element of the ring separately and allows us to add a material thickness.

Create a Cloth Surface objects from the Simulate menu (requires Cinema 4D Studio) and make the Connect Object its Child object. In the Cloth Surface object’s Attribute Manager settings, leave the Subdivisions value set to 1 and define a Thickness of 2 to give the shattered pieces a three-dimensional shape. Note that this object is only available in Cinema 4D Studio.

Now we need to assign our ring a fitting material. You can use the material supplied or you can, of course, create your own. Assign the material to the Cloth Surface object and set its Projection to Flat Mapping. Depending on the material and texture used, the Offset and Length values may have to be adjusted accordingly. Make sure the material used covers the Ring object entirely.

Scale the texture to fit, if necessary.

Defining the MoDynamics elements

To make sure the red sphere hits its target we will hurl five of them at the Ring object. Select the red sphere and then create a Cloner while pressing the Alt key. Rename it "Starter". By simultaneously pressing the Alt key the newly generated object is automatically made a Child object of the selected object and also automatically assumes its position. Set the Cloner object’s Mode to Radial to arrange the clones analogous to the shape of the ring. Set the Count value to 5 and the Radius to 103. This positions the clones so they can’t miss the ring. Keep an eye on the ZY to make sure the clones lie in a circular arrangement opposite the Ring object.

Three scene elements will be included in the MoDynamics simulation: the cloned spheres, the Ring object and the floor onto which the shattered ring will fall.

First, let’s add a Rigid Body tag from the Object Manager menu (Tags | menu) to the Floor object.

Increase the tag’s Friction value to 50% so the shattered pieces don’t slide across the floor and come to rest near to where they fall.

Also add a Rigid Body tag to the "Starter" Cloner object. Set the tag’s Trigger option to Immediately so the spheres begin moving towards the ring at the very beginning of the animation. To make sure the spheres have enough velocity to actually impact the ring, enable the Custom Initial Velocity option and set the to -1200 in the X direction. For the collision, set Individual Elements to All. All other parameters can be left as they are.

Finally, the ring itself must be assigned a Rigid Body tag in order to give it its MoDynamics properties. Assign the tag to the Fracture Object and set the Trigger

option to On Collision, which will ensure that the ring will stay in tact until impacted by the spheres. The Individual Elements option, used to define how the object reacts to collisions, should be set to All. Set the Bounce, Friction and Collision values equal to those of the Floor object.

If you used the Cinema 4D file we supplied the Gravity parameter in the Project Settings... will automatically be enabled. Otherwise this parameter will have to be adjusted accordingly (in the Dynamics tab) or else the shattered pieces will not fall correctly. For our scene, this value may have to be reduced to 400.

Click on the Play button to play the animation.

You can view the final rendered result by clicking on the following link:

 

Click on the link below to open the corresponding Cinema 4D file:


In order to demonstrate the degree to which the individual options affect the entire animation, set the parameter to Box in the Break object’s Dynamics Body tag.

The result of this minor modification can be seen here: