KDE Visual Design Group/HIG/IconDesign
Icons are pictorial representations of functions and objects, important not only for aesthetic reasons as part of the visual identity of a program, but also for utilitarian reasons as shorthand for conveying meaning that users perceive almost instantaneously. Well-designed icons improve the visual communication and strongly impact users' overall impression of visual design. Last but not least, icons are space-saving and improve usability by making programs, objects, and actions easier to identify, learn. Icon use should be consistent throughout the interface.
- Design icons with a small number of metaphors .
- Apply metaphors only once (e.g. do not use a brush twice for different options).
- Rethink conventionally used metaphors (e.g. the clipboard icon of paste).
- Antiquated metaphors might work well (e.g. a floppy is not necessarily outdated to represent save).
- Adjust the degree of abstractness according to familiarity of the metaphor.
- Use arrows only if they can easily be related to spatial features such as Previous/Next in a sequence or Up/Down in a hierarchy. Avoid using arrows metaphorically (such as for Reply/Forward or Undo/Redo).
- Attempt to use metaphors that are independent of language and culture.
- Make icons simple.
- If an icon has important details at larger sizes, rather than simply scaling it down, create unique versions of the icon at smaller sizes. Critical details may become unrecognizable when scaled down.
- Avoid using text in icon designs; it may not scale well to smaller sizes.
- Icons of a similar type share a consistent visual language (mimetypes, folders, devices, etc.).
- Follow the guidelines for presenting icons with text
- Test your icon set on strength of association, discriminatory power, conspicuousness, and, if applicable, on accessibility.
- Used for application toolbar and button actions, menus, sidebars and status and notifications. Also may be used for small (16x16) devices and places icons (folders, usb drives, etc.).
- Rely on a distinct shapes instead of fine details to distinguish between them.
- Breeze icons use primarily color #1 and #2 but also use other colors to indicate a different state.
- Icon Grey - Color used for icons in a normal state and non destructive actions e.g.: back, forward, ok, home.
- Icon Red - Color used for icons in a normal state and for destructive actions e.g.: close, delete, remove, stop. Also used in addition with color #1.
- Icon Orange - Color used in addition to color #1. Used to distinguish icons that involve "user input", also used as the color for the "busy" state in IM software.
- Icon Blue - Color used in addition to color #1. Used to distinguish icons that involve the action "select" or "insert".
- Icon Yellow - Color used in addition to color #1. Used to distinguish icons that involve a "warning", also used as the color for the "away" state in IM software.
- Icon Green - Color used in addition to color #1. Used to distinguish icons that involve "connected", "secure" or "successful" actions.
- Use colorful icons for applications, folders, mimetypes and devices.
- For Breeze icons, use colors from the full Breeze color palette as a starting point.
- Breeze icons use smooth linear gradients (bottom to top/dark to light); they are not flat.
- Application icons should be unique and easily recognizable.
- When creating an system icon theme, respect trademarks by avoiding significant alterations to application icons.
- Follow the Icon theme usage guidelines.
- For standard actions (back forward, open, save, refresh, etc.) use an icon from the platform-provided set. The KDE Platform 4.x uses the Oxygen icon set. The KDE Plasma 5.x desktop and applications use the Breeze icon set.
- If you would like to request help designing icons unique to your application, you can ask for help on the KDE Visual Design Group Forum.