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Exercise 3: Base Maps

This exercise will teach you how to produce results like this map.

Basic Drawing
Grouping and Joining
Using Transparency
Creating a Gradient Fill

You will be using the file block.ai in the below exercises.


Basic Drawing


1. Open block.ai from the Adobe Illustrator images file provided.

2. You will see that there is an Aerial image and a Road Map image on 2 different layers. Using the Zoom tool in the Tools palette, zoom into a section of the drawing.

3. Select the Rectangle tool from the Tools Palette, the 4th one down on the right.

4. Add a new layer called white background.

5. Using the rectangle tool, draw over a patch of the aerial and road map covering several blocks. Change the color to white using the Colors palette.

6. In the layers menu, to the left of the layer white background, click on the eye. The white rectangle should disappear. You can toggle the layer on and off by selecting the box where the eye appears and disappears.

Tracing the Footprint

7. Create a new layer called buildings. Select this layer.

8. Using the Pen tool, 3rd one down on the left, in the Tools palette left click to make a point, then move the tool and click again to make another point. You are creating a path.

A path is made up of one or more straight or curved segments. The beginning and end of each segment is marked by anchor points, which work like pins holding wire in place. You change the shape of a path by editing its anchor points. You can control curves by dragging the direction points at the end of direction lines that appear at anchor points.

A path is either open, like an arc, or closed, like a circle. For an open path, the starting and ending anchor points for the path are called endpoints.

If your lines have a fill, select the Color Palette and move the background (fill) square to the front. Click the white box with a slash to eliminate a fill on the object.

9. You might find drawing a bit complicated at an angle. Select everything on the Artboard Select / ALL, make sure none of layers are locked by looking for a lock in the the Layers Palette next to the eye. Click on the locks to unlock the layers.

10. Rotate the drawing so that you have vertical lines by moving the pointer near a corner handle so that the pointer changes to . Drag until the selection is at the desired angle of rotation.

11. Selecting the pen tool, you may draw straight lines holding shift while drawing with the pen tool. To close the object simply click back on the first anchor point you made.

12. You may also use the Rectangle tool and other shapes found in the Tool palette, 4th down on the right.

Grouping and Joining


You will want to group objects when you create entities such as trees or icons. You might want to group all the building footprints together. When you want to make complicated shapes without drawing them point by point, you can draw 2 overlapping rectangles, group them and merge them together. This examples will teach you how.

1. Draw 2 overlapping rectangles using the Rectangle Tool.

2. Select both rectangles by choosing the black arrow, the Selection Tool, in the tools palette, clicking both objects while holding the shift key.

3. Choose Object/ Group or Control+G to group. Now they are one entity but still 2 objects.


If you want to Join the objects and officially have 2 become 1, you will need to do the following:

4. Ungroup the 2 rectangles

5. Choose Window/ Pathfinder view the Pathfinder Tab.

6. Select both rectangles by holding down the shift key. They should be 2 separate objects.

7. In the Pathfinder palette, Under Shape Modes, choose Add to Shape Area, the first button in the row. This makes the two objects one object.

You can choose from any of the following Pathfinder effects:


Traces the outline of all objects as if they were a single, merged object. The resulting shape takes on the paint attributes of the top object.


Traces the outline of the region overlapped by all the objects.


Traces all non overlapping areas of the objects, and makes overlapping areas transparent. Where an even number of objects overlap, the overlap becomes transparent. Where an odd number of objects overlap, the overlap becomes filled.


Subtracts the front most objects from the backmost object. You can use this command to delete areas of an illustration by adjusting the stacking order. (See Stacking objects.)

Minus Back

Subtracts the backmost objects from the front most object. You can use this command to delete areas of an illustration by adjusting the stacking order. (See Stacking objects.)


Divides a piece of artwork into its component filled faces (a face is an area undivided by a line segment).

Note: When you use the Divide Pathfinder button in the Pathfinder palette, you can use the direct-selection or group-selection tool and manipulate the resulting faces independently of each other. You can also choose to delete or preserve unfilled objects when applying the Divide command.


Removes the part of a filled object that is hidden. It removes any strokes and does not merge objects of the same color.


Removes the part of a filled object that is hidden. It removes any strokes and merges any adjoining or overlapping objects filled with the same color.


Divides artwork into its component filled faces, and then deletes all the parts of the artwork that fall outside the boundary of the topmost object. It also removes any strokes.


Divides an object into its component line segments, or edges. This command is useful for preparing artwork that needs a trap for overprinting objects.

Note: When you use the Outline Pathfinder button in the Pathfinder palette, you can use the direct-selection or group-selection tool and manipulate each edge independently. You can also choose to delete or preserve unfilled objects when applying the Outline command. (See Using the Pathfinder palette.)

Hard Mix, Soft Mix, and Trap

Mix colors that overlap or adjoin.

Using Transparency

You might want to change the transparency of an object so that you can partially see through it.

1. Choose Window/ Transparency

2. Choose the right arrow and select Show Options from the drop down menu.

3. Select an object that is filled with a color. Use the slider in the Transparency option to adjust the percentage of the opacity of the object.

On the left, the orange footprint's transparency was achieved by selecting Multiply from the transparency drop down menu palette. The red footprint was created by leaving the default value of Normal in the drop down list and changing the opacity to 50 percent.

The Multiply option multiplies the base color by the blend color. The resulting color is always a darker color. Multiplying any color with black produces black. Multiplying any color with white leaves the color unchanged. The effect is similar to drawing on the page with multiple magic markers.


Both of the above footprints were colored with Overlay from the drop down menu in the Transparency palette. Overlay multiplies or screens the colors, depending on the base color. Patterns or color overlay the existing artwork, preserving the highlights and shadows of the base color while mixing in the blend color to reflect the lightness or darkness of the original color.


Gradient Fill

You might want to use gradients to fill certain objects to give them depth.

1. Select the object to fill.

2. Choose Window/ Gradient for the Gradient palette to appear.

3. Select the top right arrow and select Show Options

4. Select the Color Square in the Gradient palette, now you can see the Gradient slider.

5. Click on the small square on the slider, and move to the Color palette. Select the first color in the fill box of the Color palette. If you only see a shade of black, select the top right black arrow and change to RGB.

6. Select both colors then move the diamond between the two colors to moderate how quickly the 2 colors change.

7. If you want the border around the object to disappear, with the object selected, navigate to the color palette, and choose the no color square with the red slash for the border square.

You are ready to Draw from Photographs. Continue to Exercise 4.