Image bm804.GIF Render Group
The render group element is an active object's numeric parameter enabling to specify the succession in which individual objects are rendered (drawn). The render group value may range between 0 and 15. The rendering takes place in objects belonging to render group 0 up to objects of render group 15. Using render groups may be arbitrary. The default distribution of the render groups is as follows:
0 to 7      usual objects (default 4)
8 to 11   transparent objects (default 10, depth sorting)
12 to 15 2D pictures (default 14)
Groups 8 through 11 are default set to be used for a transparent objects. They are depth sorted. The other groups are not sorted. When creating an object or setting the transparency parameter, the object's default group is set : usual objects (opaque, resulting color not depending on the destination color) have default group 4, the transparent objects have group 10, and 2D pictures have group 14. For this reason the group must be set after the transparency has been set.

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