The Layers Preferences (in menu File / Preferences..., "Display" section, "Layers" tab) controls the appearance of layers and other display elements. The top of the dialog lists all of the technologies and their layers. It also lists special colors (at the bottom of the "Layer" list):

- BACKGROUND is the color of the background (default: gray).
- DEFAULT-ARTWORK is the color of artwork primitives that have not been assigned a specific color (default: black).
- DOWN-IN-PLACE BORDER is the color of the cell edge when editing down-in-place (default: red).
- GRID is the color of grid dots (default: black).
- HIGHLIGHT is the color of highlighting (default: white).
- INSTANCE OUTLINES is the color of unexpanded cell instances (default: black).
- MEASUREMENT is the color of the distance ruler (default: black, see Section 4-7-4).
- MOUSE-OVER HIGHLIGHT is the color of highlighting when the mouse roams over a new object (default: light blue).
- NODE HIGHLIGHT is the color of highlighted nodes in special situations (default: blue).
- PORT HIGHLIGHT is the color of highlighted ports in special situations (default: blue).
- TEXT is the color of text that has not been assigned a specific color (default: black).
- WAVEFORM* are special colors used in drawing the waveform window (see Section 4-11).
- 3D* are special colors used in drawing the waveform window (see Section 4-10-2).

Each layer has a color on the left and a pattern on the right. The color can be specified directly in the color picker, or it can be set to one of the transparent layers. If you change the color of a layer that has transparency assigned to it, the change will affects all layers assigned to that transparency.

You can draw in the pattern area to set a pattern, and you can choose from a set of predefined patterns by clicking on their image below the pattern-editing area. You can also choose an outline texture to draw.

The lower-right controls the appearance of the layer on the printed page. A separate "Use Fill Pattern" control lets you use patterns on a printer, even if they are not used on the display. The Opacity is also used for printer blending, and for some display algorithms.

When changing the background color, note that it must contrast with both the highlight color and the inverse of the highlight color (the inverse is black in the default settings).

To automatically switch to a black or white background, there are commands in the Window / Color Schemes menu that change the special colors (background, highlighting, grid, etc.) These commands do not affect individual layer appearance, just the special colors that define the overall look of the display.

- Black Background Colors sets the background to black.
- White Background Colors sets the background to white.
- Restore Default Colors sets the background to gray (the default).
- Cadence Colors, Layers and Keystrokes loads a set of colors that mimic Cadence systems. In addition to changing the colors, this command also changes key bindings (shown below) and other preferences that cannot easily be undone. It is recommended that you save your current preferences before switching to Cadence mode to make it easier to revert.

Letter | Ctrl | Plain | Other
A | Select All (2-1-1) | Add Signal to Waveform Window (4-11) | Alt: Align To Grid (4-7-2)
B | Size Interactively (2-5-1) |  |
C | Copy (6-1) | Duplicate (6-1) | Shift: Change (6-6)
D | Down Hierarchy (3-5) | Select Nothing (2-1-1) |
E | Up Hierarchy (3-5) | Down Hierarchy (3-5) | Shift: Down Hierarchy In-place (3-5)
F | Unexpand Cell All The Way (3-4) | Fill Window (4-4-1) | Shift: Expand Cell All The Way (3-4)
G | Toggle Grid (4-7-1) | Set Signal Low (4-11) |
H |  | Half Unit Movement (2-4-1) |
I | Object Properties (2-4-2) |  | Shift: Place Instance (3-3)
J | Rotate 90 Counterclockwise (2-6) | Rotate 90 Clockwise (2-6) |
K | Show Network (6-9-1) | Measure Mode (4-7-4) |
L | Find Text (4-9) |  |
M | Duplicate (6-1) | Measure Mode (4-7-4) | Shift: Move Objects By... (2-4-2)
N | New Cell (3-2) | Place Cell Instance (3-3) |
O | Open Library (3-9-2) | Overlay Signal in Waveform Window (4-11) |
P | Create Export (3-6-1) | Pan Mode (4-4-2) | Shift: Peek (3-4) Alt: Preferences (6-3)
Q | Quit (1-10-9) | Object Properties (2-4-2) |
R | Redisplay Window (4-4-2) | Remove Signal from Waveform Window (4-11) |
S | Save All Libraries (3-9-3) | Select Object... (2-1-1) |
T | Toggle Negation (5-4-2) | Place Annotation Text (2-2-1) |
U | Up Hierarchy (3-5) | Undo (6-7) |
V | Paste (6-1) | Set Signal High (4-11) |
W | Close Window (4-3) | Cycle through windows (4-3) |
X | Create Export (3-6-1) | Mirror Left <-> Right (2-6) | Alt: Show Exports (3-6-2)
Y | Redo (6-7) | Mirror Up <-> Down (2-6) |
Z | Zoom In (4-4-1) | Zoom Box (4-4-1) | Shift: Zoom Out (4-4-1)
0 | Zoom Out (4-4-1) | Wire to Poly (1-8) |
1 |  | Wire to Metal-1 (1-8) | F1: Mimic Stitch (9-6-3)
2 | Pan Down (4-4-2) | Wire to Metal-2 (1-8) | F2: Auto Stitch (9-6-2)
3 |  | Wire to Metal-3 (1-8) | F3: Cleanup Pins (2-2-3)
4 | Pan Left (4-4-2) | Wire to Metal-4 (1-8) |
5 | Center cursor (4-4-2) | Wire to Metal-5 (1-8) | F5: Run DRC (9-2-1)
6 | Pan Right (4-4-2) | Wire to Metal-6 (1-8) | F6: Array (6-4)
7 | Zoom In (4-4-1) | Wire to Metal-7 (1-8) | F7: Repeat Last Action (6-7)
8 | Pan Up (4-4-2) | Wire to Metal-8 (1-8) | F8: NCC Cells in Windows (9-7-2)
9 | Fill Window (4-4-1) | Wire to Metal-9 (1-8) | F9: Tile Windows Vertically (4-3)
= | Increase all Text Size (6-8-4) |  |
- | Decrease all Text Size (6-8-4) |  |
DEL |  | Erase (2-3) |
> |  | Show Next Error (9-1) |
< |  | Show Previous Error (9-1) |
Space |  | Switch Wiring Target (1-8) |