Accuracy of Rhino model

(Mbathala) #1

I would like to understand the model tolerance info of Rhino. What is the default accuracy type of Rhino - Relative or Absolute?
How to check whether a Rhino model uses Relative or Absolute accuracy using openNURBS API?

Mallikarjuna Bathala.

(Dale Fugier) #2

Hi @mbathala1,

This from the openNURBS source:

: m_unit_system(ON::millimeters)
, m_absolute_tolerance(0.001)
, m_angle_tolerance(ON_PI/180.0)
, m_relative_tolerance(0.01)
, m_distance_display_mode(ON::decimal)
, m_distance_display_precision(3)
  // Do not set m_unit_system.m_custom_unit_name here.
  // Doing so creates a heap allocation in the construction of
  // ON_3dmUnitsAndTolerances::DefaultValue
  // and doesn't make much sense in any case.

Of course, each 3dm file can be set to whatever tolerances the user chooses. Most of the time, the template file used to create the model dictates these values.

I don’t understand this question. The tolerance values are not dynamic. That is, changing the tolerance values does not cause existing geometry to be re-evaluated or re-computed. Rather, these values are used during the modeling process.

– Dale