This is part two of a three-part tutorial that introduces the basics of digitally drafting an underwater cave map using Adobe Illustrator. To start at part one, click here.

Introduction

This tutorial shows how to add color to an underwater cave map to represent a submerged tunnel. The layer organization used in this demo might seem overly complicated but eventually serves a purpose for roundtripping - a process that automatically adjusts drawn sections of a map to accommodate changes in the survey data, such as new loop closures, resurvey and error corrections.

I want to reiterate that this series is a simplified demo for divers interested in cartography. It is not meant to be a complete Adobe Illustrator tutorial as there are already several excellent free tutorials online.

In future tutorials, we will go into greater detail, particularly with managing and exporting the survey data, and I think you will better understand those procedures by having done this short project first.

What do I need for the tutorial?

• Adobe Illustrator, free trial here.

• Desktop or laptop, preferably with a mouse.

• The completed tutorial file from Part 1.

Quick facts

If you are already familiar with Adobe Illustrator, open the completed tutorial file from part one of this series and copy the walls and columns from the w2d Walls shp sub-layer.

Navigate to the sub-layer, w2d Detail shp, and use the Paste in Place function to add a copy of the walls into that layer. Join the open ends of the outer perimeter walls and apply a fill with color #AEE0F4. Next, remove the stroke so that only the fill color remains. Send this fill-color path to the back of w2d Detail shp.

Repeat the same steps for the columns, adding a white fill with no stroke, and then arrange them to be above the blue fill in the layers panel.

Illustrator Tutorial:
ADDING COLOR TO UNDERWATER CAVE MAPS

• by Rory O’Keefe, November 18, 2020

Adding color

Step 1: Open Illustrator.

• Open your saved Illustrator file from Tutorial 1.

• A partially completed version of Tutorial 1 will be fine – you just need a few walls and columns drawn.

Step 2: Check your layers.

• Confirm that all of the walls and columns are drawn on the w2d Walls shp sub-layer.

• If any sections are drawn on the incorrect layer, copy them, switch to the correct layer, and select Paste in Place.

Step 3: Copy/paste the walls into the detail layer.

• Click the Select All button (the small circle icon to the right of the layer name) for the w2d Walls shp layer.

• Go to Edit > Copy.

• Lock the w2d Walls layer and select the w2d Details shp sub-layer. To work on the w2d Details shp sub-layer, unlock Layer 1, w2d Details, and w2d Details shp.

• On w2d Details shp, go to Edit > Paste in Place. This will paste a copy of the walls into the details layer, directly over the walls in the walls layer. This is important because the fill color must line up exactly with the drawn walls.

Step 4: Join the walls.

• Join the open ends of the outer walls to create a closed-loop.

• Working in the w2d Details shp layer, select an outer wall and join it to the next closest section of the outer wall by selecting both paths and pressing Ctrl + J/Cmd + J, or right-click and select Join.

• Hold the Shift key while selecting multiple lengths of the outer wall to join multiple sections at a time.

• I work at a zoom percentage of about 300% and frequently alternate between the Hand Tool (H) to move around the artboard and the Direct Selection Tool (V) to select walls.

• Repeat this step until the outer wall path forms a closed loop.

Step 5: Add the fill color.

• Select the outer wall loop created in the previous step and double-click the Fill color block under the Tools Panel.

• The Color Picker window will appear – use this to select a color to represent water on the map.

• I am using color #AEE0F4 on the Dos Palmas map.

Step 6: Remove the outline.

• Remove the wall outline from the fill color by selecting the blue, outer wall loop, and navigating to the Properties Panel. In the Properties Panel, change the Stroke to 0 pt.

Step 7: Organize the details.

• Select the blue, outer wall loop, right-click, and select Send to back.

• Expand the w2d Details shp layer, scroll down to the bottom of its sub-layers, and lock the layer that contains the blue coloring.

Step 8: Make the columns white.

• Repeat Steps 4 to 6, working on the columns (interior walls) of the map.

• Join any opens ends within the larger interior columns using the same method applied to close the outer walls in Step 4.

• Use the Direct Selection Tool (V) to select all of the columns (click and drag over the map to select all).

• Apply a white Fill color and a Stroke of 0 pt.

Step 9: Save your work.

• Save the updated file for the next tutorial.

The end of part two

The next tutorial will cover the addition of cross-sections.

If you’d like to continue playing around with the map, you can try the following:

• Add/create symbols in the w2d Detail sym sub-layer to show floor-to-ceiling heights, depth, restrictions, etc.

• Add your name, cave statistics, etc to the w2d Legend layer.