3.1 Introduction to Adobe Illustrator

Adobe Illustrator is a professional vector graphics program used to create artwork from paths, shapes, lines and text that can be scaled to any size without losing quality. First released by Adobe in 1987, it is now part of Adobe Creative Cloud and is the industry standard for logos, signage, illustrations, patterns and technical graphics. In interior design, Illustrator is used to draw colourful presentation plans and elevations, design signage and wayfinding, create wall graphics and murals for printing or cutting, develop repeat patterns for fabrics, wallpapers and tiles, and prepare diagrams for presentations. Example: for a new headquarters of an agricultural cooperative, a designer uses Illustrator to draw the reception logo wall, office door signs, a floor directory and a decorative coffee-plant pattern for frosted glass partitions.

3.1.1 Uses of Illustrator in interior design

Illustrator's precision and scalability make it valuable at many stages of an interior project. Example: a designer working on a private primary school uses Illustrator to design classroom door signs, playful wall decals and a zoning diagram for the school board.

Main uses

• Presentation plans and elevations: Adding colour, textures, symbols and labels to plans imported from CAD.
• Signage and wayfinding: Designing room signs, directional signs and building directories.
• Wall graphics and murals: Creating artwork for vinyl cutting, wallpaper printing and painted murals.
• Patterns: Designing repeat patterns for fabrics, wallpapers, tiles and screens.
• Logos and branded elements: Recreating client logos accurately for branded interiors.
• Diagrams and infographics: Explaining zoning, circulation, lighting concepts and timelines.
• Fabrication templates: Preparing cutting paths for laser cutting, CNC routing and screens.
• Icons and symbols: Creating furniture symbols and icons for plans and boards.

3.1.2 Key capabilities of Illustrator

Illustrator's tools can be grouped into a few main capabilities, each covered in more detail in later topics of this chapter. Example: when designing a decorative screen for a hotel restaurant, a designer draws motifs with the Pen tool, repeats them with the Pattern tool and exports the cutting path for a laser cutter.

3.1.3 Illustrator and Photoshop compared

Illustrator and Photoshop are often used together, but they do different jobs. Knowing which to use prevents poor-quality output, such as blurry signs or unnatural photo edits. Example: a designer for a beauty salon creates the salon's sign in Illustrator and edits photographs of the salon interior in Photoshop.

3.1.4 System requirements and alternatives

Illustrator runs on modern Windows and macOS computers and needs enough memory and a capable graphics processor for complex artwork. Requirements change with each version, so they should be checked on Adobe's website. Other vector programs exist and may suit some budgets, but Illustrator skills are widely expected by employers. Example: a design department at a youth polytechnic installs Illustrator in its lab and introduces Inkscape for students to practise at home.

Hardware requirements

Alternative vector programs

3.1.5 Getting started with Illustrator

Getting started involves installing Illustrator, launching it and becoming familiar with the Home screen, from which new documents are created and recent files opened. Example: a new designer at a signage company installs Illustrator and opens an existing sign file supplied by a client to explore it.

Steps for installing and launching Illustrator

1. Create or sign in to an Adobe account: Use an email address on Adobe's website.
2. Choose a plan: Select an Illustrator or Creative Cloud plan, or a trial where available.
3. Install Creative Cloud: Download and install the Creative Cloud desktop app.
4. Install Illustrator: Click Install next to Illustrator.
5. Launch Illustrator: Open it from Creative Cloud, the Start menu or the Applications folder.
6. Explore the Home screen: View recent files, new file presets and learning resources.
7. Open a sample file: Open an existing AI or PDF file to explore the workspace.

Measurement units in Illustrator

Illustrator measures stroke widths and text in points by default, while interior drawings use millimetres, so designers often convert between the two.

Worked example: converting stroke width from points to millimetres

Width in mm = width in points × 0.3528

A wall line on a presentation plan is set to 2 pt.

Width in mm = 2 × 0.3528

Width in mm ≈ 0.71 mm