Houdini

Houdini

Assets loaded in Cinema 4D will appear as two or more elements consisting of:

• An Asset Generator, which is the parent object with the Asset control parameters
• One or more Output Generators, which are sub-objects of the Asset Generator, polygon mesh or particle.

Both generators are implemented in Cinema 4D as the same object type. Therefore, both are summarized together in the help description.

Asset Generator

The Asset Generator initially controls the subordinate Output Generators. All parameters that you defined for a given Asset in Houdini will be listed in the Asset tab and can be edited and animated.

Asset and Output Generators are linked, which means that the subordinate Output Generators can be removed from a given hierarchy and placed elsewhere while remaining linked to the Asset Generator. An Asset Generator’s Output Generators can be restored anytime even if they were deleted (Update Generators) button.

The Asset Generator’s icon will change color accordingly:

• Green: Everything is o.k. The Asset has all required input and can update all associated output generators.
• Red: An error has occurred, e.g., no input object was linked (for example, check the Asset tab (Input sub-tab) parameters to see if an input size has to be linked for a given object) or an Output Generator is missing (click on the Update Generator button in the Asset tab). While it’s running, the Asset Generator cannot create new Output Generators. However, the Asset can still instruct this to happen. If this is the case you should click on the aforementioned button to create the Output Generator.
However, the error can also lie with the Asset’s design in Houdini and how it interprets and processes input and control parameters.

The icon will also turn red if you abort a cooking process. This process can be restarted by clicking on the Cook Asset button.

Input Object

Depending on the Asset’s design, it may be necessary to link an Input object in the Asset tab’s Input sub-tab.

This is most often a polygon mesh but can also be a different element. It doesn’t matter if it is created using a polygon object, a primitive or a Generator object (e.g., an Extrude object).

Output Generator

Any number of Output Generators can belong to an Asset Generator. This is primarily defined in Houdini but Output Generators can easily be duplicated in Cinema 4D. If an Output Generator’s Asset Generator is deleted it can also be restored (Update Asset button).

The following Output Generators are available:

• Mesh Generators: Creates polygon meshes that can be made editable (converted to a polygon object) at any time by selecting the object and pressing the c key. The link to the Asset Generator will then be broken.

• Particle Generators: make the Asset-controlled Houdini particles available as Thinking Particles.

Output generators now offer a series of visible tags (which were also available before but were hidden). These tags cannot be modified, copied or deleted and are mareked with an "h" in the Object Manager to show that they are controlled by the Houdini Asset. These tags can be used normally (e.g., a Polygon Selection tag can be linked with a Material tag to restrict the material to a selection) but cannot be modified.