---
title: 3.1.2 Optimise and troubleshoot drawing imports
description: "A little extra care during the preparation of a drawing can pay dividends for ease of subsequent analysis. Key points to be aware of include: - Avoid unnecessary detail. The fewer lines used to describe a drawing, the faster the…"
url: "https://isovists.org/user-guide/3-1-2-optimise-and-troubleshoot-drawing-imports/"
updated: "2021-04-05"
category: "3 How To... / 3.1 Perform Basic Functions:"
---

# 3.1.2 Optimise and troubleshoot drawing imports

A little extra care during the preparation of a drawing can pay dividends for ease of subsequent analysis. Key points to be aware of include:

- Avoid unnecessary detail. The fewer lines used to describe a drawing, the faster the analysis will run and the clearer the outcomes will be. Details included in CAD are often extraneous to the issues of spatial definition; such details should be turned off if possible, or allocated as ‘annotations’.
- Check the drawing to ensure that the lines intersect. Small gaps between line ends or where walls meet, can occasionally cause issues in the scan calculations; for instance, causing false results in an occlusivity field.
- Wherever possible, simple lines, basic shapes (circles, rectangles), and smoothed curves should be used in the drawing, rather than many very small fragment segments.
- If your import issue is persistent, please [notify us](http://isovists.org/reporting-an-issue/) and we will try and assist you.