Difference between revisions of "Reference:Ovus"

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<p>Where <em>Bottom_radius</em> is a float value giving the radius of the bottom sphere and <em>Top_radius</em> 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 <code>distance</code> is a float value that represents the length between the center of the two spheres, defaulting to <em>Bottom_radius</em>. The <code>radius</code> float value represents the inner circle of the connecting torus and it's default is twice the greater of either <em>Top_radius</em> or <em>Bottom_radius</em>. The <code>precision</code> float value is the tolerance used for the root solving of the connecting torus. If additional accuracy is required you can now add the <code>[[Reference:Sturm Object Modifier|sturm]]</code> object modifier.</p>
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<p>Where <em>Bottom_radius</em> is a float value giving the radius of the bottom sphere and <em>Top_radius</em> 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 <code>distance</code> is a float value that represents the length between the center of the two spheres, defaulting to <em>Bottom_radius</em>. The <code>radius</code> float value represents the inner circle of the connecting torus and it's default is twice the greater of either <em>Top_radius</em> or <em>Bottom_radius</em>. The <code>precision</code> float value is the tolerance used for the root solving of the connecting torus, and it's default is <code>1e-4</code>. If additional accuracy is required you can now add the <code>[[Reference:Sturm Object Modifier|sturm]]</code> object modifier.</p>
  
 
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Latest revision as of 11:07, 25 July 2017

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 greater of either Top_radius or Bottom_radius. The precision float value is the tolerance used for the root solving of the connecting torus, and it's default is 1e-4. If additional accuracy is required you can now add the sturm 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
  • The distance must be greater than or equal to Bottom_radius
  • The radius must be greater than or equal to half the sum of Bottom_radius, Top_radius and Vertical_distance

An ovus 2D section

RefImgOvus3D.png

The ovus and it's constituent 3D shapes

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.

See also: UV Mapping.

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