
## Polyhedra Provided by Number

There are fifteen polyhedra that can be created by setting its type number from 0 to 14. These are

| type | name                                 | number of faces |
| ---- | ------------------------------------ | --------------- |
| 0    | Tetrahedron                          | 4               |
| 1    | Octahedron                           | 8               |
| 2    | Dodecahedron                         | 12              |
| 3    | Icosahedron                          | 20              |
| 4    | Rhombicuboctahedron                  | 26              |
| 5    | Triangular Prism                     | 5               |
| 6    | Pentagonal Prism                     | 7               |
| 7    | Hexagonal Prism                      | 8               |
| 8    | Square Pyramid (J1)                  | 5               |
| 9    | Pentagonal Pyramid (J2)              | 6               |
| 10   | Triangular Dipyramid (J12)           | 6               |
| 11   | Pentagonal Dipyramid (J13)           | 10              |
| 12   | Elongated Square Dipyramid (J15)     | 12              |
| 13   | Elongated Pentagonal Dipyramid (J16) | 15              |
| 14   | Elongated Pentagonal Cupola (J20)    | 22              |

## MeshBuilder

usage :

```javascript
const polyhedron = BABYLON.MeshBuilder.CreatePolyhedron("oct", options, scene); //scene is optional and defaults to the current scene
```

| option          | value                                                                                              | default value                    |
| --------------- | -------------------------------------------------------------------------------------------------- | -------------------------------- |
| type            | _(number)_ polyhedron type in the range [0,14]                                                     | 0                                |
| size            | _(number)_ polyhedron size                                                                         | 1                                |
| sizeX           | _(number)_ X polyhedron size, overwrites the _size_ property                                       | 1                                |
| sizeY           | _(number)_ Y polyhedron size, overwrites the _size_ property                                       | 1                                |
| sizeZ           | _(number)_ Z polyhedron size, overwrites the _size_ property                                       | 1                                |
| custom          | _(polygonObjectReference)_ a polyhedron object, overwrites the _type_ property                     | null                             |
| faceColors      | _(Color4[])_ array of _Color4_, one per face                                                       | Color4(1, 1, 1, 1) for each side |
| faceUV          | _(Vector4[])_ array of _Vector4_, one per face                                                     | UVs(0, 0, 1, 1) for each side    |
| flat            | _(boolean)_ if false, a polyhedron has a single global face, _faceUV_ and _faceColors_ are ignored | true                             |
| updatable       | _(boolean)_ true if the mesh is updatable                                                          | false                            |
| sideOrientation | _(number)_ side orientation                                                                        | DEFAULTSIDE                      |

To understand how to set _faceUV_ or _faceColors_, please read about [Face Colors and Textures for a Box](/divingDeeper/materials/using/texturePerBoxFace) taking into account the right number of faces of your polyhedron, instead of only 6 for a box.

## Examples

The full set of 15: <Playground id="#PBLS4Y " title="Full Set Of 15 Polyhedra" description="Playground example showing all 15 provided polyhedra."/>
Dodecahedron with FaceUVs: <Playground id="#PBLS4Y#1 " title="Dodecahedron with FaceUVs" description="Playground example of creating a dodecahedron with faceUVs."/>

## Mesh

usage :

```javascript
const polyhedron = BABYLON.Mesh.CreatePolyhedron("oct", options, scene); //scene is optional and defaults to the current scene
```

This is the same format as that for _MeshBuilder_



## Custom Polyhedra
These are a further range of polyhedra that you can create although they need more steps to achieve. This is the reason for the *custom* option. All the other options, other than *type*, can be used with custom polyhedra.


1.  Visit <Playground id="#WL3U6F" title="Custom Polyhedra" description="Simple example of custom polyhedra in Babylon.js."/> and minimize the code editor by unchecking the box by Editor under the Gear icon &#9881; (Options) and note the polyhedron names under the mouse pointer.  
![Select a Polyhedron](/img/how_to/Mesh/polyhedra1.jpg);

2. From the polyhedra.js file at https://github.com/BabylonJS/Extensions/tree/master/Polyhedron find the required name
```javascript
HeptagonalPrism : {
"name":"Heptagonal Prism",
"category":["Prism"],
"vertex":[[0,0,1.090071],[0.796065,0,0.7446715],[-0.1498633,0.7818315,0.7446715],[-0.7396399,-0.2943675,0.7446715],[0.6462017,0.7818315,0.3992718],[1.049102,-0.2943675,-0.03143449],[-0.8895032,0.487464,0.3992718],[-0.8658909,-0.6614378,-0.03143449],[0.8992386,0.487464,-0.3768342],[0.5685687,-0.6614378,-0.6538232],[-1.015754,0.1203937,-0.3768342],[-0.2836832,-0.8247995,-0.6538232],[0.4187054,0.1203937,-0.9992228],[-0.4335465,-0.042968,-0.9992228]],
"face":[[0,1,4,2],[0,2,6,3],[1,5,8,4],[3,6,10,7],[5,9,12,8],[7,10,13,11],[9,11,13,12],[0,3,7,11,9,5,1],[2,4,8,12,13,10,6]]},
```

 
3. Copy/paste the wanted polyhedron object in your code like this :

```javascript
const heptagonalPrism = { "name":"Heptagonal Prism", "category":["Prism"], "vertex":[[0,0,1.090071],[0.796065,0,0.7446715],[-0.1498633,0.7818315,0.7446715],[-0.7396399,-0.2943675,0.7446715],[0.6462017,0.7818315,0.3992718],[1.049102,-0.2943675,-0.03143449],[-0.8895032,0.487464,0.3992718],[-0.8658909,-0.6614378,-0.03143449],[0.8992386,0.487464,-0.3768342],[0.5685687,-0.6614378,-0.6538232],[-1.015754,0.1203937,-0.3768342],[-0.2836832,-0.8247995,-0.6538232],[0.4187054,0.1203937,-0.9992228],[-0.4335465,-0.042968,-0.9992228]],
"face":[[0,1,4,2],[0,2,6,3],[1,5,8,4],[3,6,10,7],[5,9,12,8],[7,10,13,11],[9,11,13,12],[0,3,7,11,9,5,1],[2,4,8,12,13,10,6]]};

const heptPrism = BABYLON.MeshBuilder.CreatePolyhedron("h", {custom: heptagonalPrism}, scene); //scene is optional and defaults to the current scene

//also possible
const heptPrism1 = BABYLON.Mesh.CreatePolyhedron("h", {custom: heptagonalPrism}, scene); //scene is optional and defaults to the current scene
```
 &nbsp;
 &nbsp;   
HeptagonalPrism: <Playground id="#PBLS4Y#2" title="HeptagonalPrism" description="Simple example of a heptagonalPrism."/>
Heptagonal Prism with changed sizes: <Playground id="#PBLS4Y#3" title="HeptagonalPrism With Changed Sizes" description="Simple example of a heptagonalPrism with changed sizes."/>
Heptagonal Prism with face colors: <Playground id="#PBLS4Y#4" title="HeptagonalPrism With Face Colors" description="Simple example of a heptagonalPrism with face colors."/>


## Polyhedra
There are a multitude of polyhedra, too many for all to be created by individual names. Often their names take too long anyway and Babylon.js provides 15 common ones via number. There are many beyond these 15 and those can be created from custom data sets provided in the form of Playground examples. 

The twenty sided icosahedron has the interesting property of approximating a sphere. By dividing each face into triangles and then mapping the resulting vertices onto a sphere it gives a better approximation of a sphere. The solids formed are called icospheres and provide a more regular distribution of triangles around a sphere then the *CreateSphere* method.

Other sphere approximations can be provided by geodesic and Goldberg polyhedra. Like the icosphere a geodesic polyhedron is based on an icosahedron and formed from equilateral triangles, in this case, however, their arrangement depends on two parameters, m and n, both integers. A Goldberg polyhedron is the dual of a geodesic one, and vice-versa. A dual of a polyhedron is formed by mapping its vertices to the faces of the dual and its faces to the dual's vertices. A Goldberg polyhedron is made up of 12 pentagonal and many hexagonal faces and has the advantage of a planet shaped hexagon-grid world.

![Geodesic Vertices](/img/snippets/geo30.png)  
The Arrangement of Vertices for a Geodesic Poly with m = 6 and n = 0, 1, 2 in order

type	name	number of faces
type 0	name Tetrahedron	number of faces 4
type 1	name Octahedron	number of faces 8
type 2	name Dodecahedron	number of faces 12
type 3	name Icosahedron	number of faces 20
type 4	name Rhombicuboctahedron	number of faces 26
type 5	name Triangular Prism	number of faces 5
type 6	name Pentagonal Prism	number of faces 7
type 7	name Hexagonal Prism	number of faces 8
type 8	name Square Pyramid (J1)	number of faces 5
type 9	name Pentagonal Pyramid (J2)	number of faces 6
type 10	name Triangular Dipyramid (J12)	number of faces 6
type 11	name Pentagonal Dipyramid (J13)	number of faces 10
type 12	name Elongated Square Dipyramid (J15)	number of faces 12
type 13	name Elongated Pentagonal Dipyramid (J16)	number of faces 15
type 14	name Elongated Pentagonal Cupola (J20)	number of faces 22

option	value	default value
option type	value (number) polyhedron type in the range [0,14]	default value 0
option size	value (number) polyhedron size	default value 1
option sizeX	value (number) X polyhedron size, overwrites the size property	default value 1
option sizeY	value (number) Y polyhedron size, overwrites the size property	default value 1
option sizeZ	value (number) Z polyhedron size, overwrites the size property	default value 1
option custom	value (polygonObjectReference) a polyhedron object, overwrites the type property	default value null
option faceColors	value (Color4[]) array of Color4, one per face	default value Color4(1, 1, 1, 1) for each side
option faceUV	value (Vector4[]) array of Vector4, one per face	default value UVs(0, 0, 1, 1) for each side
option flat	value (boolean) if false, a polyhedron has a single global face, faceUV and faceColors are ignored	default value true
option updatable	value (boolean) true if the mesh is updatable	default value false
option sideOrientation	value (number) side orientation	default value DEFAULTSIDE

Provided Polyhedra

Polyhedra Provided by Number

MeshBuilder

Examples

Mesh