Skip to Main Content
Created by Oto Lukss
Created on Jan 12, 2023

Create models in local coordinates

Looking for easier definition of local coordinate systems for mesh reconstruction. It is no secret that building designers do not work in real world coordinate systems nor it is reasonable because of large coordinates, local scale factors and limited 3D model space. So there are two deliverables when capturing existing buildings one is a reality mesh of building and surrounding area in real world coordinates to be used for analysis and other is building in local coordinates for using in CAD/BIM modelling. Mostly X axis is chosen from longest dimension of building and origin in center of it. What Contextcapture is currently lacking is an option to easy define such local system as ENU doesn`t allow to change axis orientation so CAD users have to adjust view orientation which can cause issues later. Also if creating model only from point cloud there is no option to use constraints to set axis orientation.

Planners, surveyors, and project managers often use local coordinate systems for construction projects. For good reasons, they avoid mistake-prone scale factors, minimize map projection distortion, circumvent grid revisions, and keep a site’s coordination dataset to a more manageable size.

Please work together with Microstation team to create a workflow and solution to this problem. Ideally it should create a Reality mesh which contains custom coordinate system with Affine/Helmert transformation parameters to existing SRS.