RhinoCommon SDK

## UnitSystem Enumeration |

ON::LengthUnitSystem identifies a length unit system
United States customary length units references:
http://www.nist.gov/pml/wmd/metric/upload/frn-59-5442-1959.pdf
http://en.wikipedia.org/wiki/United_States_customary_units
http://en.wikipedia.org/wiki/International_yard_and_pound

Syntax

Members

Member name | Value | Description | |
---|---|---|---|

None | 0 | ON::LengthUnitSystem::None indicates no length unit system. The scale factor when converting between a specified unit system and None is always 1.0. ON::LengthUnitSystem::None is used as a unit system for models and instance defitions that should be imported or referenced with no scaling applied. | |

Angstroms | 12 | 1 angstroms = 1.0e-10 meters | |

Nanometers | 13 | 1 nanometer = 1.0e-9 meters | |

Microns | 1 | 1 micron = 1.0e-6 meters | |

Millimeters | 2 | 1 millimeter = 1.0e-3 meters | |

Centimeters | 3 | 1 centimeter = 1.0e-2 meters | |

Decimeters | 14 | 1 decimeter = 1.0e-1 meters | |

Meters | 4 | SI meter length unit | |

Dekameters | 15 | 1 dekameter = 1.0e+1 meters | |

Hectometers | 16 | 1 hectometer = 1.0e+2 meters | |

Kilometers | 5 | 1 kilometer = 1.0e+3 meters | |

Megameters | 17 | 1 megameter = 1.0e+6 meters | |

Gigameters | 18 | 1 gigameter = 1.0e+9 meters | |

Microinches | 6 | 1 microinches = 2.54e-8 meters = 1.0e-6 inches | |

Mils | 7 | 1 mil = 2.54e-5 meters = 0.001 inches | |

Inches | 8 | 1 inch = 0.0254 meters = 1/12 foot | |

Feet | 9 | 1 foot = 0.3048 meters (12 inches) | |

Yards | 19 | 1 foot = 0.3048 meters = 12 inches | |

Miles | 10 | 1 US statute mile = 1609.344 meters = 5280 feet | |

PrinterPoint | 20 | Printer distance 1/72 inches (computer points). | |

PrinterPica | 21 | Printer distance 1/6 inches (computer picas). | |

NauticalMile | 22 |
Terrestrial distance, 1852 meters.
Approximately 1 minute of arc on a terrestrial great circle. See http://en.wikipedia.org/wiki/Nautical_mile . | |

Astronomical | 23 | Astronomical unit distance. http://en.wikipedia.org/wiki/Astronomical_unit 1.495979e+11 // http://units.nist.gov/Pubs/SP811/appenB9.htm An astronomical unit (au) is the mean distance from the center of the earth to the center of the sun. | |

Lightyears | 24 |
Light Year
http://en.wikipedia.org/wiki/Light_year 9.46073e+15 meters http://units.nist.gov/Pubs/SP811/appenB9.htm A light year is the distance light travels in one Julian year. The speed of light is exactly 299792458 meters/second. A Julian year is exactly 365.25 * 86400 seconds and is approximately the time it takes for one earth orbit. | |

Parsecs | 25 | 1 parsec = 3.08567758e+16 meters References: http://en.wikipedia.org/wiki/Parsec (3.08567758e+16 meters) http://units.nist.gov/Pubs/SP811/appenB9.htm (3.085678e+16) | |

CustomUnitSystem | 11 | Custom unit systems x meters with x defined in ON_3dmUnitsAndTolerances.m_custom_unit_scale. | |

PrinterPoints | 20 | 1 printer point = 1/72 inch | |

PrinterPicas | 21 | 1 printer pica = 1/6 inch | |

NauticalMiles | 22 | 1 nautical mile = 1852 meters Approximately 1 minute of arc on a terrestrial great circle. Reference: http://en.wikipedia.org/wiki/Nautical_mile | |

AstronomicalUnits | 23 | 1 astronomical unit = 1.4959787e+11 meters An astronomical unit (au) is the mean distance from the center of the earth to the center of the sun. References: http://en.wikipedia.org/wiki/Astronomical_unit (1.4959787e+11 meters) http://units.nist.gov/Pubs/SP811/appenB9.htm (1.495979e+11 meters) | |

LightYears | 24 | 1 light year = 9.4607304725808e+15 meters A light year is the distance light travels in one Julian year. The speed of light is exactly 299792458 meters/second. A Julian year is exactly 365.25 * 86400 seconds and is approximately the time it takes for one earth orbit. References: http://en.wikipedia.org/wiki/Light_year (9.4607304725808e+15 meters) http://units.nist.gov/Pubs/SP811/appenB9.htm (9.46073e+15 meters) | |

CustomUnits | 11 | The name of a custom unit and the conversion to meters are saved in the ON_UnitSystem class. | |

Unset | 255 | The ON::LengthUnitSystem::Unset is used to indicate no unit system is set. This is a differnt condition from ON::LengthUnitSystem::None. |

Version Information

See Also