Sprite Object: Rubble
The Sprite object can generate simple primitive objects to give the illusion of rubble or gravel.
If you select 'Rubble' in the 'Sprite type' drop-down menu, the interface changes and you see the available parameters for the rubble:
For the 'Groups Affected' tab and the buttons at the bottom of the interface, please see the 'Common interface elements' page.
Parameters
Type
This drop-down lets you select the shape of the rubble object. The rubble is created from a Platonic primitive and the options in this drop-down are identical to the 'Type' drop-down in the Platonic object. There is one addition - 'Random' which selects randomly from the available types.
Hint: 'Dodeca' produces a good result without being too polygon-heavy.
Subdivision levels
The sprite object can subdivide the basic object to give more polygons. This is important when deforming the object (see 'Deformation' below). The default value is 1, but higher values may give better results; however, as more polygons are generated the editor playback may be slower. A value of 2 is a good compromise. A value of zero means no subdivision will occur.
Use Smooth Subdivisions
If this switch is checked, the subdividing process will use smooth subdivisions. This gives a smoother object but it becomes more spherical in shape, which may not be desirable.
Deformation
This slider will deform the object randomly along polygon normals. The greater the value, the more the deformation.
Add Phong Tag
If this switch is checked a phong tag is added to the object; the angle can be adjusted in the 'Phong Angle' setting. Adding a phong tag will give a smoother object, which may or may not be what you want.
Phong Angle
The phong angle to use if a phong tag is added.
Local Min. Scale, Local Max. Scale
These settings allow you to set the minimum and maximum scale of each object. They are applied in addition to any scale set by the sprite object. So for example, if the particle scale is 2 and the local scale in the rubble setting is also 2, the final scale value is 4. In general it is recommended that you keep the particle scale to 1 and use the local scale settings to determine the size of the rubble. The actual scale used is a random value between the minimum and maximum settings.
Smooth Rubble
If this switch is checked the object is further subdivided one more time using smooth subdivision.
Why have two subdivisions? These settings are independent of one another, but the initial subdivision is carried out before the object is deformed, and the 'Smooth Rubble' subdivision takes place after deformation. As a result they produce distinctly different effects. You can use them together in any combination.