“Front” is the color of the paper's face: the sheet as it lies on the table before anything is cut, and every part of it that is still there afterwards. When you cut, the front is what you cut away from. A new design starts with a black front.
What it does
The front color fills the sheet. Draw a shape over it and the shape becomes a cut: the paper inside is lifted out, the hole it leaves shows the ground, and the piece, flipped over an edge, shows the back. What remains of the sheet, with all its holes, is drawn in the front color.
Paper can come back, too. Draw a shape inside a hole and the paper returns to the sheet, and it returns face up, in the front color: it came off a piece and goes back where it was.
The Front card holds the color: a swatch to select it or drag it onto another card, the name “Front”, the hex code, a padlock and the sliders for the current “Color space”. In the harmony order, Front, Back, Ground, the front comes first, so with the Front locked a harmony gives the next place to the back and the one after to the ground.
In the artwork export the sheet is drawn last, on top of everything, as a single shape filled with the front color. The cut-lines file, which a cutting machine or a craft knife would follow, is the outline of the paper missing from that shape.
The starting black is not quite empty. It carries a hidden hue, a blue, so raising its saturation or brightness lands on a color chosen to sit with the others.
Why it works this way
The front is the figure you start with: the whole sheet, uncut. Every notan begins as one shape, the rectangle, and grows by subtraction. Because every cut takes paper from the front and gives it to the back, the front and back together always add up to one sheet's worth of paper, which is what makes the result something you could actually cut.
A black front on a white ground is the classic start for the same reason a pencil drawing starts on white paper: the strongest contrast there is. It makes the first cut read instantly as a hole.
The metaphor
The front is the face of a sheet, what bookbinders call the recto when it is a page. Paper really does have a face and a back. Papermakers distinguish the wire side, which lay against the screen of the mold and may carry its faint pattern, from the felt side, the other face; for many papers one side is the intended right side, smoother or better sized.
The metaphor holds for the essentials: a face, a reverse, and edges where you cut. It breaks in the details a hand would notice. Real paper has a grain, a texture and a thickness, and a cut edge shows its core. Cut many colored mount boards and you see a white bevel; cut a thick black card and its edge may be gray. The app's front is flat color right to the edge, with no thickness at all, which is why it is always clean and never quite paper.
A history
In art
The word notan came to English from Japanese nōtan, written with characters meaning dense or dark and pale or light. The scholar Ernest Fenollosa brought the idea to the United States, and Arthur Wesley Dow made it a cornerstone of his book Composition (1899), which taught a generation of American artists to design with masses of dark and light.
Cut paper is the purest form of the idea, and many traditions found it. Chinese paper-cut, jianzhi, often in red paper, was inscribed on UNESCO's list of the intangible cultural heritage of humanity in 2009. German and Swiss Scherenschnitte, scissor cuts, and the silhouette portrait did the same, often in black. The silhouette takes its name from Étienne de Silhouette, briefly France's finance minister in 1759, though exactly why his name stuck to cut profiles is uncertain. In the twentieth century Matisse drew with scissors, and since the 1990s Kara Walker has cut black paper figures at the scale of a room, set against white walls: a black front, a white ground, and all the meaning in the edge.
The psychologist Edgar Rubin gave the front its scientific name in 1915, in his Copenhagen thesis on visually experienced figures: the figure, the region that seems to have a shape and to stand in front, against a ground that seems to run on behind it. His best-known picture, a vase that is also two faces, shows how easily the two can change places.
In printing
Relief printing works exactly like a notan's front. In a woodcut or a linocut, the uncut surface of the block takes the ink and prints; everything the carver removes prints as bare paper. Carving is subtraction from a face, and the finished print is what remains. Metal type works the same way: the raised printing surface of each letter is called its face, which is where the word typeface comes from.
Printers also think about the front as the first side: the side printed first, which a book calls the recto and a printer the front of the sheet. The second side is the subject of the next chapter.
In technology
Graphics software calls the front the fill: the color inside a shape. In the SVG format, which Studio Notan exports, the sheet is a single path with a fill attribute set to the front color, and the holes are cut into that path by a rule called even-odd: draw a line from any point out past the edge of the design and count how often it crosses the outline. Odd, and the point is paper; even, and it is a hole.
The black-on-white start has a history on screens too. Most early computers showed light text on a dark screen. The Xerox Alto of the 1970s, then Apple's Lisa and the Macintosh of 1984, put black on white instead, like ink on paper, and the Macintosh's MacPaint made drawing in black on a white page feel like drawing.
In professional software
Other programs call the front the fill, the positive shape or the face. The idea that transfers is subtraction: a notan’s sheet is one filled shape with holes in it, and every vector and CAD program has a way to cut one shape out of another.
- Adobe Illustrator. Select the sheet and the shapes inside it, and ‘Object › Compound Path › Make’ (⌘8, or Ctrl+8 on Windows) turns them into one filled shape with holes. The ‘Attributes’ panel switches between the even-odd fill rule, the one Studio Notan uses, and non-zero winding. ‘Minus Front’ in the ‘Pathfinder’ panel cuts the shapes on top out of the one beneath.
- Adobe Photoshop. A layer mask cuts without throwing anything away: where the mask is black the layer is hidden, and where it is white the layer shows. Paint a shape in black and it becomes a hole onto whatever lies below.
- Autodesk Fusion (formerly Fusion 360). Draw a sketch on a face, then ‘Extrude’ (
E) with the operation set to ‘Cut’ to remove material. The ‘Appearance’ dialog (A) applies to whole bodies or to single faces, so one face of a part can differ from the rest. - Cricut Design Space. ‘Slice’ cuts one shape out of another and keeps the pieces as separate shapes. Each color on the canvas is cut from its own sheet of material, so the front color stands for a real sheet you load good side up.
What carries over. Think of the front as one shape with holes, not many shapes side by side. Clean cut files, clean fills and clean solid models all depend on it. The pitfall is vocabulary. In Illustrator, front and back mean stacking order, which object lies on top, so ‘Minus Front’ removes the upper object and ‘Bring to Front’ moves a shape up the pile. Neither has anything to do with a side of the paper.
Try this
- Cut a shape and flip it, then change the front to a warm red. The sheet and all it keeps change together; the flipped piece does not.
- Give the front and the ground the same color. The sheet disappears into the ground and only the flipped pieces remain, floating.
- Drag the Front swatch onto the Back card and see the flips and the sheet trade colors.