Accessibility
Made to be read, and used, more than one way.
Delta's colors, focus and controls are made to WCAG 2.2 level AA. On top of that, its Settings let each person change how the window looks and moves. Graphs can be built without a mouse.
In Settings
Open Settings with the Settings button, from View > Settings, or with Ctrl+, (Cmd+, on a Mac). A change takes effect at once and is kept for the next time Delta starts.
A typeface made to be told apart
Atkinson Hyperlegible Next, from the Braille Institute, is drawn so that letters easily mistaken for each other, such as I, l and 1, or O and 0, look different. Choose it in place of the system font.
Text size up to 200%
Text and controls grow together, in steps from 100% to 200%, and the window is laid out again at the new size.
Less motion
Follow the system’s setting, or turn animations, transitions and smooth scrolling off whatever the system says.
Higher contrast
Stronger text, borders and graph lines, in the light theme and the dark one. The theme itself follows the system, or is set to light or dark.
A stronger focus outline
A thicker outline, with a gap round it, shows which control the keyboard is on against any background.
Underlined links, and notifications that wait
Links can be underlined so they do not depend on color. Notifications can stay until you close them, instead of going after a few seconds.
From the keyboard
Everything on the canvas can be done without a mouse. On a Mac, use Cmd where this says Ctrl.
| Keys | What they do |
|---|---|
| Tab | Move between the cards on the canvas, their inputs and outputs, and the other controls. |
| Enter | On a card, open its settings. Space does the same. |
| Arrow keys | On a card, move it. Hold Shift to move it further. |
| EnterthenEnter | On an output, start a connection; then on an input, finish it. Escape cancels. |
| Delete | On a card, remove it. On an input or output, remove its connection. |
| Ctrl+Z | Undo. Ctrl+Y or Ctrl+Shift+Z redoes. |
| Ctrl+0 | Fit the graph to the window. Ctrl+= and Ctrl+- zoom the canvas in and out. |
| Ctrl+, | Open Settings. It is also in the View menu. |
| Escape | Close a dialog. The keyboard goes back to where it was before the dialog opened. |
What assistive technology is told
Delta gives screen readers names, states and announcements, so that what is shown on the screen is also said.
Cards say what they are
A card is read out by its name and kind of component, and says when it has problems or warnings.
What happens is announced
Starting, finishing or cancelling a connection, and removing one, are announced as they happen.
Notifications are read out
Each notification is announced as it appears, and an error or a success says which it is in words, not only by its color. Errors are read out at once; the rest wait their turn.
Every button has a name
Buttons that show only an icon have a name for screen readers, and dialogs keep the keyboard inside them until they close.
The standard it keeps to
- Text has a contrast of at least 4.5:1 with what is behind it; borders of controls and the lines of the graph have at least 3:1.
- Every control shows that it has the keyboard with an outline, not by a change of color alone.
- A card with problems or warnings shows an icon for each, not only a color, and a screen reader reads out what they are.
- Each kind of component has a color on the canvas, and its name is always on its card.
Not done yet
Delta has not yet been tested with screen readers: NVDA, JAWS and VoiceOver. We expect there are things to put right, and we would like to hear about them. A graph is a picture, and following one by ear is harder than following one by eye, so we especially want to know how that goes.
This website
The site uses the same colors as the app and is made to the same standard. It can be used from the keyboard, with a link at the top to skip to the content, and it follows your system's light or dark theme and its setting for reduced motion. It works at 200% zoom and on a phone's screen.
Something in the way?
If something in Delta or on this site is hard or impossible for you to use, tell us what it was and what you use to read or move around, and we will work on it.
Write to support@delta-etl.com