Reference:Ovus

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An ovus is a shape that looks like an egg. A Change in version 3.8 has extended the syntax of the ovus object by adding radius, distance and precision controls.

The syntax is as follows:

ovus {
  Bottom_radius, Top_radius [radius Inner_radius] [distance Vertical_distance] [precision Root_tolerance]
  [OBJECT_MODIFIERS...] 
  }

Where Bottom_radius is a float value giving the radius of the bottom sphere and Top_radius is a float specifying the radius of the top sphere. The top and bottom spheres are connected together with a suitably truncated lemon, or self intersection of a torus, that is automatically computed so as to provide the needed continuity to the shape. The distance is a float value that represents the length between the center of the two spheres, defaulting to Bottom_radius. The radius float value represents the inner circle of the connecting torus and it's default is twice the Bottom_radius. The precision float value is the tolerance used for the root solving of the connecting torus. Additionally sturm is now allowed as an object modifier.

RefImgOvus2D.png
  • The center of the top sphere lies on the top of the bottom sphere.
  • The bottom sphere of the ovus is centered at the origin.
  • The top sphere of the ovus lies on the y-axis.
  • The minor radius of the lemon is twice the largest radius.

An ovus 2D section

RefImgOvus3D.png

The ovus and it's constituent 3D shapes

Whenever the top radius is bigger than twice the bottom radius, the ovus degenerates into a sphere with an offset center. There are a lot of variations in the shape of the ovus.

Note: According to the ratio of the radius, the pointy part is the smallest radius, but is not always on top!

RefImgDemoOvus.jpg

Evolution of ratio from 0 to 1.95 in 0.15 steps.

Note: See the following MathWorld references for more information about the math behind how the ovus object is constructed.