Occasionally you may wish to vary layer material assignments in the app, rather than having them preset on import. To do this, the process is simple:

• When preparing your drawing for import, organise your drawing elements onto appropriate layers, but leave them un-named.
• Save the drawing as either a dxf, dwg or svg file.
• Launch the Isovist_App.
• Select ‘Import/Export’ from the primary menu at the top left of the screen, and then ‘Open Scan or Plan file’. A file dialogue box should subsequently open to allow the import file to be chosen.
• After choosing the file, the screen should switch to a blinking icon whilst the file loads and the drawing is translated; this will take longer for larger files.
• When complete, the drawing should appear on your screen. With no layers having been pre-set, the whole drawing will appear black. 
• Within the drawing and setup menu, a sub menu called ‘Layer Management’ should appear, with four layer control categories; solid, transparent, reflective and annotations. 
• Within each category you should be able to view your original drawing layers, and toggle them on and off. As you do so, the material designation in the viewport plan drawing should change accordingly.
• Once the required changes have been made, it is advisable to re-check the selected analysis areas (see section 3.1.6).