How to prepare an accurate base map

Mapping is a fundamental part of all stages and scales of architectural design. This tutorial will help you start mapping systematically. By keeping your layers of information organised, it will be easier to demonstrate your research and back up your design choices. Strict focus on scaling this document accurately also allows you to change scales and paper sizes easily if needed. In this tutorial, we will be creating a map of Greater Melbourne, but these principles can be applied at all scales.

Step 1: Collecting data

A good place to start would be vector information of your site from sources like Spatial Datamart. You can follow the tutorial from Robert on how to use Spatial Datamart. The VICMAP_LITE file has many useful layers of information for a base map at this scale. You can also explore resources under different themes pertaining to your brief. Make sure to use the same options for every file you request. Also, order them in small batches, download links will be sent much faster that way.

Step 2: Overlaying data

Create a copy of the DWG file with the most information and open it in AutoCAD. If all your orders from Spatial Datamart use the same projection, you can paste relevant information from other files using ‘Paste to Original Coordinates’.

If all else fails, use reference points to align and scale drawings. In this case, that would be using the pointy tip of Fort Nepean on the Mornington Peninsula.

Step 3: Preparing a page layout

Once you have pasted the desired layers of information, click on the ‘Layout’ tab on the bottom-left. The ‘Page Setup Manager’ window should appear. Click on the relevant layout (usually ‘Layout1’) and click ‘Modify’.

Under ‘Printer/Plotter’, select ‘AutoCAD PDF (General Documentation)’. This gives you full bleed options for paper sizes.

Make sure you are using the correct units (millimetres) and scale (1:1) under ‘Plot Scale’.

Step 4: Making a new viewport

Select and delete the viewport that is created by default. We want to use all available paper space.

Type the command ‘VIEWPORTS’ and click ‘OK’ on the dialogue box. When prompted to draw the dimensions of the viewport, type ‘F’ for ‘Fill’ and hit Enter.

Now the viewport should fill the whole page.

Step 5: Adjusting the scale

Double-click on the viewport to switch from ‘Paper Space’ to ‘Model Space’. By default, the view is set to ‘Zoom Extents’, which means everything in the drawing is centred. If irrelevant objects are in frame, select your desired objects or a rectangle containing that view, and click ‘Zoom Object’ or type the command ‘ZOOM’ and use the arrow keys to select it.

This Spatial Datamart file is already at 1:1000. In order to show it at 1:500,000, it needs to be set at 1:500. This is a custom option I had made. While in Model Space, click the decimal number on the bottom-right and scroll down to ‘Custom’. Click ‘Add’ to create your own scale. For 1:500, 1 corresponds to paper units and 500 to drawing units.

Once you are done, click the lock icon to prevent accidentally changing the view.

Step 6: Saving the file for export

Save the file as an AutoCAD 2010 Drawing so it can be opened with Adobe Illustrator.

Step 7: Setting up in Illustrator

Once opened in Illustrator, select ‘Original Size’ and click ‘OK’.

The layers from AutoCAD are maintained, but the artboard is set to Illustrator’s default. Go to ‘File’ > ‘Document Setup’ > ‘Edit Artboards’ or hit Shift + O.

In the Options bar, use the drop-down menu or key in the paper dimensions to resize the artboard.

You will notice that the rectangle representing the paper (in blue below) is smaller than the artboard. Select everything with Ctrl/Cmd + A.

Using the Move tool (V), resize it to the artboard while holding Shift. Alternatively, go to ‘Object’ > ‘Transform’ > ‘Scale’. Scale it uniformly and get the right percentage by typing in *one dimension of the artboard* / *corresponding dimension of the frame*. For example, 841/795.944. Click ‘OK’.

Align everything to the upper-left corner using the Move tool (V). If there is no artwork beyond the edges of the frame, you can use the Options bar to align it precisely.

Save the document as an Adobe Illustrator (.ai) file. This is now the base of your map.

Next steps:

This base map can be used throughout your design process to show iterations of your evolving research and focus. Since it is organised by layers, you can start editing strokes, fills, opacities and blend modes to represent your research best. You can also annotate using the Text tool (T) and add other information using the Pen tool (P) and Image Trace. Alternatively, other programs and more traditional means can be used to enrich your map.

Here are some examples of iterative work I have done to give an idea of what you can accomplish.

Site area, water catchments and elevation map of Victoria (Image Traced) 1:500,000 @ A3
Transport networks, vegetation, water bodies, bird coastal habitats and urban areas from Spatial Datamart 1:250,000 @ A1
Overlaying research with focus on highlighting public land, nature parks and reserves in contrast to built areas 1:250,000 @ A1
Final map with more information about geological features, faults around Westernport Bay and coastal inundation estimates in the coming century 1:250,000 @ A1

Other useful resources: