New Geodesics

Patterns for modern geodesic structures.

From a long-term fascination for Geodesic structures.

 

Last revised 2024 Apr 24


Great, what next! READ about the website. LOOK at the Structures. BUY something special. DIG into the technical details. WHO wrote the website. SEE a Spherical Shell video. So cool!

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When Bucky (Buckminster Fuller) and friends were in their prime, the available mathematical tools, especially for spherical coordinates, were primitive. For this reason, most of the classic geodesic dome material is about how to use simple math in order to cover a spherical surface originally defined with big triangles with littler triangles. This allowed shorter struts, and bigger spheres. Class I, Class II, and alternate breakdown are classic methods of subdividing one triangle into (easily computable) smaller triangles. Easy to see how the octahedron and icosahedron, which had more original triangles, became the fundamental starting spheres used at the time.

 

Times have changed. The omnipresent personal computer has incredible computing power.

 

The LGdome program made the illustrations in this book. LGdome searches for patterns on the surface of a sphere, limited by various constraints. Some of the patterns found are in the general published literature. Some are believed unique to this publication. Some are breakdowns of regular polyhedra. Some are not. The patterns are examined for useful properties aesthetics, ease of manufacture, ease of construction, strength of structure, and efficient use of available building materials being among them. Due to the strength of a geodesic roof, Shelter is safer. The shape means the Shelter receives less wind loading, and is quieter. Shelter includes houses, cabins, sheds, and greenhouses. The minimum material to build one allows easy transport to off-grid locations.

A pattern with few different elements is easier to make and build. Consider a hub. Each hub connects the correct number of struts in the correct order. Each strut connects to the hub with a bevel angle out of the sphere plane. Each strut has an internal angle separating it from the adjacent strut. The simplest construction would have those two angles the same for all struts. The tetrahedron, octahedron, cube, icosahedron, and dodecahedron have only have one strut length, and order is automatic. More complex hubs might have every strut, angle, and bevel different. Modern CNC machinery can manufacture the different hubs automatically, but keeping track of the different hubs, and struts during transport and construction is a chore.

Similar statements may be said of the faces, and struts. For this reason, those sphere patterns that are deemed too complex to build have arbitrarily not been included in the site. Contact the author if you have an interest in a pattern that was excluded.

Face sub-pattern groups can make it easier to build and assemble. The face LCD with the folding pattern offer clues to useful sub-patterns. Entire 6-face hubs are pre-assembled as hexagons and then attached as a unit. Various other breakdown sub-patterns allow the same utility. New breakdown patterns are shown for the tetrahedron, cube, and dodecahedron..

Planning to publish the folding patterns, and 3D-printed spheres. Also under consideration is full details of each component of a shape for manufacture or construction.

Contents

Spherical Dimensions.
Excluded Material.
PFE formulae and 12 hub5 pattern
Full Triacon formula.

Patterns, Spherical and other

DELAUNAY VORONOI
S4 Tetrahedron
S5 Triangular bi-pyramid V5 Triangular prism from S5.
S6 Octahedron V6 from S6 - cube from Octahedron
S7 pentagonal bi-pyramid. V7 from S7
S8 V8 from S8. 20
S9 V9 from S9
S10 V10 from S10
S12 -Icosahedron V12 Dodecahedron from S12
S14 V14 from S14
S16 V16 from S16
S17 V17 from S17
S18 V18 from S18
S18O 2vOctahedron V18O from S18O 2vOctahedron
S20 V20 from S20
S22 V22 from S22
S22D from S7 V22D from S22D
S24 V24 from S24
S27 V27 from S27
S28 V28 from S28
S32 5Dodecahedron V32 from S32
S38 V38 from S38
O3A38 VO3A38 from O3A38
S40 19Tetrahedron V40 from S40
S42 2vIcosahedron V42 from S42
S44 14cube V44 from S44
S46 22tetrahedron V46 from S46
S48 V48 from S48
S50 V50 from S50
S72 V72 from S72
S92 3vIcosahedron V92 from S92
S122D 2vTriangulatedDodecahedron
Group coloring

Spherical Pattern Names.

Spp names the basic spheres generated using Delaunay methods. pp is the number of points on the sphere. These spheres are composed of triangular faces. Vff names the Voronoi spheres generated from Delaunay spheres. ff is the number of faces on the sphere. Voronoi patterns tend to have 4-sided, 5-sided, and 6-sided faces. This may be augmented by a common name if known to the author. "S4" is a tetrahedron. "S12" is an icosahedron.

D may be appended to indicate 2v Class 1 (alternate) Method 1 breakdown. Similarly, DD indicates the 3v breakdown. S42D is the 2v-icosahedron pattern commonly used for small projects.

When new breakdowns are discovered within a pattern, -mm indicates the degree of breakdown, and it is often followed by the name of the original pattern.

Spherical Dimensions

The radius is chosen as 1.0 for Delaunay patterns and most use. Voronoi patterns circumscribe the sphere and touch the sphere at its center point. Thus have an edge point radius greater than 1.

Excluded Material

A text file containing four tables which define the element geometry. Point table has the point coordinates in cartesian and spherical. Hub table has the geometry needed for hub construction. Face table has the face geometry. Edge table has the geometry needed to construct struts.

An OpenScad file to bring the shape into the 3D print world.

An .DXF file to show the faces, colors, and lines.

Many spheres were excluded by the Author for various reasons.

Email the Author if you want access to excluded material.

PFE formulae and 12 hub 5 pattern

. Let P be the number of points on the sphere. When the sphere is evenly covered by triangles, the number of faces may be computed from

F = (P-2)*2

The number of edges may be computed from

E = (P-2)*3

This supports the notion that you must have three points to make 2 triangular faces (think both sides), which will then have three edges. Thus you can choose how many faces or edges you want, and then compute the number of points needed on the sphere.

Consider a sphere covered in triangles. A new point must go into the interior of one of the triangles. This new point would create 3 faces from the original face, thus adding 2 faces. The three new connecting edges, combine with the existing edges to define the new face sides. One new point gives 2 new triangles and 3 new edges.

Delaunay Spheres with more than 12 points tend to have 12 hubs with 5 spokes each. But they do not occur in the same spherical locations as in the icosahedron.

Both of these properties hold for spheres made totally of evenly distributed points gathered into delaunay triangles. But compare S22 with S22D, which shows an exception for triangulated spheres. Voronoi spheres are not covered in triangles, and are an exception.

Full Triacon formula.

This material generated from "Geodesic Domes" by Borin Van Loon. The book explains the concept rather well. I recommend it to anyone interested in the subject.

In a "Full 2V Triacon", One point is added at the centroid of each original face, and resulting total points can be collected, Delaunay-fashion, into a new set of faces.

A tetrahedron with 4 points and 4 faces would have 8 points and 12 faces. The result is a cube, with each face represented by two right triangles.

An S5 with 5 points and 6 faces would have 11 points and 20 faces..

An S6 with 6 points and 8 faces would have 14 points and 24 faces.

An S7 with 7 points and 10 faces would have 17 points and 30 faces..

An S_ with n points and (n-2)*2 faces would have 3n-4 points and 6n-12 faces.

Thus, if a delaunay sphere exists with n points with 8 or more points, there would be "full triacon" spheres with 14, 17, 20, 23, 26, 29, 32, 35, 38, 41, 44, 47, ...... points.

Spherical Patterns

This section contains the patterns. It is organized from simple to complex, and ordered in increasing number of points on the sphere surface. The top and side view of most of the spheres is given, as well as the unfolded template. The template may be used to make a folding model out of stiff paper. It will reveal much about the relationship between the different faces. The coloring serves to identify the different face groups.

 

S4 Tetrahedron

VISIT Tetrahedron. 4 points, 4 faces, 6 edges.

The Voronoi of a tetrahedron is a bigger tetrahedron (not shown)

no FLAT no LEFT no TOP

 

S5 Triangular bi-pyramid

VISIT Triangular bi-pyramid. 5 points, 6 Faces:@0.96825, 9 Edges in two groups: 6@1.41421, 3@1.73205

no FLAT no LEFT no TOP

 

V5 Voronoi from S5

VISIT Triangular prism. 6 points, 5 Faces, 9 Edges in two groups: 6@1.41421, 3@1.73205

no FLAT no LEFT no TOP

 

S6 Octahedron

VISIT Octahedron. Also called a square bi-pyramid. 6 points, 8 Faces:, 12 Edges

no FLAT no ALL

 

V6 Voronoi from S6

VISIT Voronoi Cube. Points 8, Faces 6@area 4.00000, Edges 12@Length 2.00000

no FLAT no ALL

 

S7 pentagonal bi-pyramid

7 points, 10 Face Areas:@0.75605, 15 Edges in two groups: 5@1.17557, 10@1.41421

no FLAT no LEFT no TOP

 

V7 Voronoi from S7

10 Points, 7 Face Areas in 2 groups: 5@2.90617, 2@3.63271, 15 Edge Lengths in 2 groups: 10@1.45309, 5@2.00000, Note two other patterns with 10 points.

no FLAT no LEFT no TOP

S8

If all triangles - 8 Points, 12 Faces, and 18 Edges. But two pair of triangles form a square, in two cases. Thus reduced to 8 Points, 10 Faces in 2 groups: 8@0.67397, 2@1.36242(square), 16 Edges: 8@1.16722, 8@1.29391 Bottom has side view, folding template, and top view.

no FLAT no LEFT no TOP

 

V8 Voronoi from S8

10 Points, 8 Face Areas@2.52342, 16 Edge Lengths in 2 groups: 8@1.24486, 8@2.04149

no FLAT no LEFT no TOP

 

S9

9 Points, 14 Faces: 6@0.58736, 6@0.62668, 2@0.65699 21 Edges: 12@1.13527, 6@1.23176, 3@1.40605

no FLAT no LEFT no TOP

 

V9 Voronoi from S9

14 Points, 9 Face Areas in 2 groups: 3@1.91844, 6@2.17399 21 Edge Lengths in 3 groups: 3@0.68551, 6@1.12057, 12@1.39114.

no FLAT no LEFT no TOP

 

S10

10 Points, 16 Face Areas in 2 groups: 8@0.55465, 8@0.56583, 24 Edge Lengths in 3 groups: 8@1.07658, 8@1.09061, 8@1.28310

no FLAT no LEFT no TOP

V10 Voronoi from S10

16 Points. 10 Face Areas in 2 groups: 2@1.63188, 8@1.83372. 24 Edge Lengths in 3 groups: 8@0.70774, 8@1.27743, 8@1.28165

no FLAT no LEFT no TOP

S12 -Icosahedron

12 Points, 20 Face Areas@0.47873, 30 Edge Lengths@1.05146

no FLAT no LEFT no TOP

 

V12 Dodecahedron from S12

20 Points, 12 Face Areas@1.38757. 30 Edge Lengths@0.89805

The Voronoi dodecahedron differs from the Spherical dodecahedron. The Voronoi faces are tangent to the sphere at the face center. The Delaunay faces touch the sphere at the face points. Thus Voronoi dimensions are slightly bigger.

no FLAT no LEFT no TOP

 

S14

24 Faces in 2 groups: 12@0.41130, 12@0.41772. 36 Edges in 3 groups: 12@0.88836, 12@1.02700, 12@1.04005.

no FLAT no LEFT no TOP

 

V14 from S14

24 points. 14 Face Areas in 2 groups: 12@1.11904, 2@1.28400 36 Edge Lengths in 3 groups: 12@0.69845, 12@0.70300, 12@0.98245

no FLAT no LEFT no TOP

 

S16 7-Tetrahedron Breakdown

Hub 16 Points. 28 Faces: 4@0.34305, 12@0.36003, 12@0.38030. 42 Edges: 6@0.82982, 12@0.89008, 12@0.90559, 12@1.03859.

LCD is 4. 7 face tetra breakdown triangles are 1 red, 3 green, and one-half of 6 yellow.

no FLAT no LEFT no TOP

 

V16 from S16

28 points. 16 Face Areas in 2 groups: 12@0.94008, 4@1.05230, 42 Edge Lengths in 4 groups: 12@0.47120, 12@0.76741, 12@0.81757, 6@0.91192,

LCD is 4. Tetra breakdown

flat FLAT left TOP top LEFT

 

S17

12 Hub5 and 4 Hub6. 30 Face Areas in 3 groups: 10@0.32912, 10@0.35142, 10@0.35729 45 Edge Lengths in 4 groups: 20@0.84557, 10@0.88580, 10@0.93361, 5@1.17557

no FLAT no LEFT no TOP

 

V17 from S17

30 Hub3: 17 Face Areas in 3 groups: 2@0.88648, 5@0.89869, 10@0.90384: 45 Edge Lengths in 4 groups: 5@0.06034, 10@0.56668, 10@0.71781, 20@0.91615,

no FLAT no LEFT no TOP

 

S18 (LGdome)

18 Hubs 2@4,8@5, 8@6: 32 Face Areas: 8@0.32026, 8@0.32540, 8@0.32540-rev, 8@0.34149: 48 Edges: 8@0.80568, 16@0.83714, 8@0.85510, 8@0.91417, 8@1.04286

Contrast to S18O 2vOctahedron, which also has 18 Points. Yes, there is more than one stable pattern for a set of points. Note the 4-part rotational symmetry. Face LCD 8 allows tetrahedron and octahedron breakdowns.

no FLAT no LEFT no TOP

 

V18 from S18

32 Hub3: 18 Face Areas in 3 groups: 2@0.77486, 8@0.82389, 8@0.87133: 48 Edge Lengths in 5 groups: 8@0.28461, 8@0.54470, 8@0.67701, 16@0.78911, 8@0.88023,

noFLAT noLEFT noTOP

 

S18O 2vOctahedron

32 Faces in 2 groups: 24@0.28974, 8@0.43301: 48 Edges in 2 groups: 24@0.76537, 24@1.00000:

Formed by Classic 2v class 1 Method 1 breakdown of S6 Octahedron. Compared to the S18, This S18O has less variety of edges and faces, and flat dome equator. The S18 has smaller ranges of face area and edge length area, and so is more uniform, and stronger.

noFLAT noALL

 

V18O Voronoi from S18O

32 Hub3: 18 Face Areas in 2 groups: 6@0.68629, 12@0.92893: 48 Edge Lengths in 2 groups: 24@0.50730, 24@0.82843:

Voronoi of 2vOctahedron

noFLAT noALL

 

S20

20 Hubs: 12@5, 8@6: 36 Faces in 4 groups: 12@0.28312, 12@0.30162, 6@0.30486, 6@0.30904: LCD is 6. 54 Edges in 7 groups: 6@0.77714, 12@0.78711, 12@0.80381,12@0.83735, 3@0.84256, 6@0.96213, 3@1.07431:

Three-part Rotational symmetry. Might work well in dome groups. The (blue) vertical triangles meet with a 5 degree bevel at their common edge.

flatFLAT topTOP sideLEFT third

 

V20 Voronoi from S20

36 Hub3: 20 Face Areas in 4 groups: 6@0.71837, 6@0.73765, 6@0.75527, 2@0.77366: 54 Edge Lengths in 8 groups: 1@0.10378, 2@0.10390, 6@0.34025, 12@0.56679, 3@0.60297, 12@0.66649, 6@0.78028, 12@0.78553,

noFLAT noLEFT noTOP

 

S22

22 Hubs 12@5, 6@6, 4@6: 40 Face Areas in 4 groups: 12@0.26427, 4@0.27445, 12@0.27501R, 12@0.27501L: 60 Edge Lengths in 4 groups 12@0.73567, 24@0.77408, 12@0.79612, 12@0.91938.

10::1 Tetrahedron symmetry. Center blue triangle, surrounded by 3 red, 3 yellow, and 3 green triangles.

flatFLAT sideLEFT topTOP

 

V22 from S22

40 Hub3: 22 Face Areas in 3 groups: 12@0.64297, 4@0.68351, 6@0.68702: LCD = 2. 60 Edge Lengths in 4 groups: 12@0.31579, 12@0.54179, 24@0.62361, 12@0.73866:

noFLAT noLEFT noTOP

 

S22D from S7

22 Hubs 5@4, 2@5, 15@6: 40 Face Areas in 3 groups: 20@0.23777, 10@0.26073, 10@0.34378: 60 Edge Lengths in 5 groups: 10@0.61803, 10@0.75569, 10@0.77503, 10@0.82251, 20@0.93162:

Class 1 method 1 breakdown from S7. The red and yellow triangles are mirrors of each other, together forming face group 1.

flatFLAT sideLEFT topTOP

 

V22D Voronoi from S22D

40 Points. 22 Face Areas: 5 @ 0.54633, 2 @ 0.60500, 5 @ 0.66787, 10 @ 0.74019 60 Edge Lengths: 20 @ 0.37490, 10 @ 0.59300, 10 @ 0.63224, 10 @ 0.64984, 10 @ 0.84072

LCD is 2.

noFLAT noLEFT noTOP

 

S24

24 hubs: 44 Faces in 3 groups: 24@0.24552, 8@0.25488, 12@0.25614: 66 Edges in 4 groups : 24@0.71573, 24@0.76720, 12@0.78056, 6@1.01217:

This has 6 square faces. the triangular 12@0.25614 are square 6@0.51228:

noFLAT noLEFT noTOP

 

V24 Voronoi from S24

38 Hubs. 32h3 and 6h2: 24 Face Areas: 24@0.59942: 60 Edge Lengths: 12@0.47167, 24@0.51802, 24@0.74170

Note that all faces are identical in size and "arrowhead" shape. Arrowhead is not symmetrical about long axis.

no FLAT no LEFT no TOP

 

S27

27 Hubs: 50 Faces in 3 group areas: 20@0.21675, 10@0.22627, 20@0.22908: 75 Edges in 6 group lengths: 20@0.68175, 20@0.70053, 10@0.70170, 5@0.72099, 10@0.77245, 10@0.82808.

Rotational 5-part symmetry, and mirror top to bottom.

noFLAT noLEFT noTOP

 

V27 Voronoi from S27

50Hub3: 27 Face Areas: 10@0.50332, 2@0.50994, 10@0.53873, 5@0.54225: 75 Edge Lengths: 10@0.29687, 10@0.37422, 5@0.45139, 30@0.54440, 20@0.58603

noFLAT noLEFT noTOP

 

S28

28 Hubs. 12h5, 16H6

52 Faces: 12@0.21146, 12@0.21312, 12@0.21409, 12@0.22205, 4@0.22451

78 Edges: 12@0.64688, 6@0.67043, 12@0.67981, 12@ 0.71145, 12@0.71726, 12@0.72005, 12@0.81489,

13:1 tetra

noFLAT noLEFT noTOP noTetra

 

V28 Voronoi from S28

52Hub3

28 Faces: 12@0.48260, 4@0.50961, 12@0.52174,

78 Edges: 12@0.27405, 12@0.45605, 12@0.46687, 12@0.49064, 6@0.52543, 12@0.54973, 12@0.63605,

noFLAT noLEFT noTOP

 

S32 enhanced Dodecahedron

32 Hubs: 60 Faces: 60@0.18995: 90 Edges: 60@0.64085, 30@0.71364

Each dodecahedron face replaced by 5 identical isosceles triangles.

noFLAT noLEFT noTOP

 

V32 Voronoi from S32

60 Hub3: 32 Face Areas in 2 groups: 12@0.41566, 20@0.44427: 90 Edge Lengths in 2 groups: 30@0.34010, 60@0.49151

noFLAT noLEFT noTOP

 

S38

38 Hubs:

72 Faces: 12@0.15153, 12@0.15939, 12@0.15939, 12@0.16335, 12@0.16530, 12@0.16530:

108 Edges: 24@0.56949, 24@0.59042, 12@0.59383,12@0.61738, 12@0.62516, 12@0.63945

noFLAT noLEFT noTOP

 

V38 Voronoi from S38

72 Hub3:

38 Face Areas in 5 groups: 12@0.34932, 12@0.36226, 6@0.36402, 6@0.36402, 2@0.37649:

108 Edge Lengths in 7 groups: 12@0.15883, 12@0.33617, 12@0.38065, 12@0.38444, 12@0.40569, 24@0.45834, 24@0.50834 .

From dark blue center, a multi-color radial pattern is repeated 6 times.

noFLAT noLEFT noTOP

 

O3A38 3V Octahedron alternate breakdown

38 Hubs:

72 Face Areas: 24 @ 0.13844, 24 @ 0.14902, 24 @ 0.19338:

108 Edge Lengths: 12 @ 0.49923, 24 @ 0.52683, 48 @ 0.64707, 24 @ 0.71873

noFLAT noLEFT noTOP

 

VO3A38 Voronoi from O3A38

72 Hub3:

38 Face Areas: 6 @ 0.29824, 24 @ 0.35935, 8 @ 0.41086,:

108 Edge Lengths: 24 @ 0.20209, 48 @ 0.40054, 12 @ 0.54322, 24 @ 0.54611

.

noFLAT noLEFT noTOP

 

S40 19Tetrahedron

40 Hubs-12@5, 28@6: 76 Face Areas: 12 @ 0.14641, 24 @ 0.15154, 24 @ 0.15210, 12 @ 0.15865, 4 @ 0.16889 114 Edge Lengths: 12 @ 0.54987, 6 @ 0.55878, 24 @ 0.56333, 24 @ 0.58517, 12 @ 0.62452, 24 @ 0.63285, 12 @ 0.65956

19::1 Tetrahedron symmetry. Both of the 24-element face groups have half/half mirror images

noFLAT noLEFT noTOP

 

V40 Voronoi from S40

76 Hub3: 40 Face Areas: 12 @ 0.32017, 4 @ 0.33908, 12 @ 0.34946, 12 @ 0.35038: 114 Edge Lengths: 12 @ 0.25699, 24 @ 0.32734, 12 @ 0.34937, 24 @ 0.41377, 24 @ 0.42726, 12 @ 0.47655, 6 @ 0.47900:

10:1 Tetrahedron symmetry.

noFLAT noLEFT noTOP

 

S42 2vIcosahedron

Hubs( 12@5, 30@6 ) 80 Faces in 2 groups: 60@0.13930, 20@0.16540 LCD=20. 120 Edges in 2 groups: 60@0.54653, 60@0.61803

Looking at the left side view, notice the bottom half could be rotated 36 degrees and still have a valid Geodesic. Curious.

noFLAT noLEFT noTOP

 

V42 Voronoi for S42

80@Hub3: 42 Face Areas: 12@0.29316, 30@0.33428: 120 Edge Lengths: 60@0.33395, 60@0.41279,

7::1 Cube. 2 red &5 yellow

noFLAT noLEFT noTOP

 

S44 14 cube

44 Hubs: 78 Faces in three groups: 24@0.13168, 48@0.14177, 6@0.29040: 120 Edges in 4 groups: 24@0.53888, 24@0.55692, 48@0.55805, 24@0.60580

14:1 breakdown of a cube (count square as two triangles). Has square openings.

This is a great shape to use for a cubby house or tree house. 6 square openings equally spaced make natural windows or door opening. A square floor fits in easily. Internal poles which follow the original cube edges are natural for curtains, or counter top edges, etc.

noFLAT noALL

 

V44 Voronoi from S44

72 Hub3 and 6 Hub4. 44 Face Areas: 24@0.30152, 12@0.30985, 8@0.31787: 120 Edge Lengths: 24@0.30254, 48@0.36768, 24@0.39922, 24@0.48891,

noFLAT noLEFT noTOP no

 

S46

46Hubs: 88 Face Areas in 7 groups: 12@0.12779, 12@0.13081, 16@0.13182, 12@0.13231, 12@0.13527, 12@0.13798, 12@0.13866 LCD is 4. 132 Edge Lengths in 9 groups: 24@0.51460, 24@0.53247, 12@0.53309, 12@0.54648, 12@0.55172, 12@0.57299, 12@0.59810, 12@0.62066, 12@0.63568,

22:1 tetra breakdown, maybe.

noFLAT noLEFT noTOP no

 

V46 Voronoi from S46

96 Hub3: 46 Face Areas in 5 groups: 12@0.27780, 6@0.29324, 4@0.29504, 12@0.29849, 12@0.30007: 132 Edge Lengths in 11 groups: 12@0.21169, 12@0.23788,12@0.27299, 12@0.32988, 12@0.36413, 12@0.38440, 12@0.40274, 12@0.41106, 12@0.42427, 12@0.42574, 12@0.44692:

noFLAT noLEFT noTOP

 

S48

48Hubs.

92 Face Areas in 5 groups: 24@0.12363, 24@0.12691,24@0.13055, 12@0.13124, 8@0.13213 LCD = 4.

138 Edge Lengths in 7 groups: 24@0.51232, 24@0.51865, 24@0.53793, 24@0.55236, 24@0.55527, 12@0.60130, 6@0.72440,

12@0.13124 triangles are 6@0.26248 squares. Tetra breakdown would be 23::1

noFLAT noLEFT noTOP

 

V48 Voronoi from S48-92-132

86 Hubs.

48 Face Areas in 2 groups: 24@0.27392, 24@0.28502: Lcd=24.

132 Edge Lengths in 6 groups: 12@0.25082, 24@0.30902, 24@0.33730, 24@0.35982, 24@0.39928, 24@0.47317,

noFLAT noLEFT noTOP

 

S50

50Hubs. 96 Faces in 5 groups: 12@0.11694, 24@0.12029, 24@0.12512,12@0.12519,24@0.12557: LCD=12. 144 Edges in 9 groups: 12@0.49310, 24@0.50442, 12@0.51260, 24@0.51746, 12@0.52422, 12@0.54482, 12@0.55645, 24@0.57245, 12@0.61645

Six-part rotational symmetry. Possible 2, tetra, cube, and dodeca breakdowns.

noFLAT noLEFT noTOP

 

V50 Voronoi from S50

96 Hub3. 50 Face Areas in 5 groups: 12@0.25453, 12@0.26964, 12@0.27027, 12@0.27418, 2@0.27767: LCD=2. 144 Edge Lengths in 9 groups:12@0.19362, 24@0.26509, 12@0.31840, 12@0.32690, 12@0.34063, 12@0.36993, 24@0.37136, 24@0.40672, 12@0.42206

noFLAT noLEFT noTOP

 

S72

72 Hubs. 140 Faces: 20@0.08382, 60@0.08486,60@0.08786: LCD=20. Possible tetra(4), icosa(20) breakdowns. 210 Edges: 60@0.42482, 30@0.43008, 60@0.43998, 60@0.48801

noFLAT noLEFT noTOP

 

V72 Voronoi from S72

140 Hub3: 72 Face Areas in 2 groups: 12@0.17165, 60@0.18433: LCD=12. 210 Edge Lengths in 4 groups: 60@0.19840, 60@0.28725, 60@0.31583, 30@0.32046,

noFLAT noLEFT noTOP

 

S92 3vIcosahedron

92 Hubs. 180 Faces in 3 groups: 60@0.06462, 60@0.06493, 60@0.07300: LCD=60. 270 Edges in 4 groups: 30@0.36050, 60@0.37018, 120@0.40281, 60@0.42766

noFLAT noLEFT noTOP

 

V92 Voronoi from S92

180 points 92 Face Areas: 12@0.12887, 60@0.14185, 20@0.14693: LCD=4. 270 Edge Lengths: 60@0.18859, 120@0.23819, 60@0.27368, 30@0.28177

noFLAT noLEFT noTOP

 

S122D 2vTriangulatedDodecahedron.

122 Hubs. 240 Face Areas in 4 groups: 60@0.04964, 60@0.05061R, 60@0.05061L, 60@0.05339: LCD=60. 360 Edge Lengths in 5 groups: 60@0.32413, 60@0.32534,120@0.34057, 60@0.36284, 60@0.37601

noFLAT noLEFT noTOP no

/* end of spheres */

Group coloring

The face index color is set by face size and shape groups. Red is index 1, used for the smallest triangle. Yellow is index 2. Green is index 3. And so on. The color black is used for lines by the system, so not used here for face color. Many spheres with too many different triangle shapes and sizes are assumed to be difficult to work with, and are not in this book.

 

DXF color

PenToColorMapEntry_t( 0, RGB( 255, 255, 255 ) ), black(not used)

PenToColorMapEntry_t( 1, RGB( 255, 0, 0 ) ), red. Usually the smallest face.

PenToColorMapEntry_t( 2, RGB( 255, 255, 0 ) ), yellow. Next smallest face.

PenToColorMapEntry_t( 3, RGB( 0, 255, 0 ) ), green

PenToColorMapEntry_t( 4, RGB( 0, 255, 255 ) ), aqua or light blue

PenToColorMapEntry_t( 5, RGB( 0, 0, 255 ) ), blue

PenToColorMapEntry_t( 6, RGB( 255, 0, 255 ) ), purple

PenToColorMapEntry_t( 7, RGB( 0, 0, 0 ) ), white

PenToColorMapEntry_t( 8, RGB( 128, 128, 128 ) ), grey

PenToColorMapEntry_t( 9, RGB( 190, 190, 190 ) ), light grey