Leadlight Designer: From Picture to Numbered Pattern

How to use it, step by step

1. Jobs. Name the job in the bar above the tools. It autosaves in this browser under that name and reopens next visit; Open job switches between jobs, New job clears the work surface for the next one, Save file / Open file move a job as a .json. Undo covers everything, including loading a picture, Turn into pattern, borders, size changes and New job.
2. Load. Drop a photo or a scanned cartoon on the Picture tab, or pick a sample, or start a blank panel. The picture sits under the design as a backdrop; whatever is already on the work surface (a border, shapes, lines) stays.
3. Design setup. Say what is fixed: Must fit an opening (the outside stays exactly as typed; pictures are fitted or stretched inside it and inside any border) or Free (the panel follows the picture; a border keeps its widths and is re-laid). Set the shape (rectangle, arch, circle, oval, octagon). Change any of it later: the border is re-laid, never stretched, and the artwork reframes inside.
4. Prepare. If the panel looks angled the tool says so: press Straighten and drag the four corners onto the panel corners. Use Patch to paint out a hand or a shadow.
5. Trace. Choose Lead came or Copper foil, draw a Keep-detail box over any part that needs finer pieces, then press Turn into leadlight pattern. A short check follows: where the picture goes (inside your border, best fit or stretched), what to do with a frame found in the picture, holes, true circles and the safe fixes. The pattern lands inside the border you already built.
6. Style. Once the picture is in, pick a pattern style from the previews (bold lead through to very fine foil, or line drawing), or set the Detail slider yourself.
7. Review flags. Press Review flags. Fix the safe ones does the tiny pieces, slivers, deep curves and obvious loose ends; Next flag walks you through the rest with a Bridge, Split or Extend button for each — a loose end shows its choices (A straight on, B to the nearest line) drawn on the pattern.
8. Adjust. Drag junctions and the neighbours follow (junctions on the panel edge slide along it while Edge lock is on). Draw line adds a line between any two points, even in free space; Erase line removes one. Right-click any piece, line or junction for its menu. Border and Shape are on the toolbar; shapes drag and resize as objects.
9. Symmetry and objects. Turn Symmetry on in the toolbar and every line or shape you add is mirrored across the dot-dash axes; painting mirrors too. Shift-click lines (or a piece) and press Make object to turn them into a named object — drag it, rotate, flip, scale, copy it, or save it to your library and place it in another design.
10. Inspector. Whatever you click shows up as numbers on the Pattern tab: glass, size, how many other pieces share the shape, and grain for a piece; centre, width and height for a shape; centre and radius for a circle; position, size and rotation for an object; x and y for a junction; the came size for a line, with Make it vertical / horizontal / 45° when it is nearly there. Type a value and press Enter. Drag a selected line and the whole line bends smoothly with its ends fixed; Curve handles shows its bends as squares with Bézier handles for exact shaping; the white dots move one bend at a time.
11. Symmetry. With Symmetry on, every edit is mirrored: move a junction or a bend, smooth, straighten or erase a line, drag a shape or a circle, and the mirror-image lines follow. Junctions on the axis stay on it. Shapes, bevels and library objects drop with their mirror copies.
12. Delete a piece. Select a piece and press Delete piece (strip, Inspector, right-click or the Delete key): it merges into the neighbour it shares the most lead with, and the Inspector lets you choose a different neighbour. A shape is simply removed.
13. Borders and bevels. Border on the toolbar opens a gallery sized to your panel. Adding a border to a design that already has one shrinks everything again; tick "remove the existing outer band first" to swap a border. Shape, Bevel and library objects float on the cursor with width, height and angle in the Inspector; click to drop them, and they never leave the panel. A rectangular bevel dropped on a border band spans the band; if the band is the wrong width the strip offers to widen the whole border, the corner blocks only, or to set the bevel in as it is. Anywhere else a bevel is a solid: the lines around it stop at its edge. Add your own bevel sizes on the Pattern tab.
14. Circles. Pick the Circle tool and click any arc of a sketched circle: the whole ring is followed round, fitted and replaced with a true circle, with the lines that met it joined on. The Inspector then shows its centre and radius, which you can type, plus Centre in panel and Concentric. Drag inside the circle to move it. Undo if it is not what you meant.
15. Colour. Pick a swatch and click pieces, or use the colour picker in the piece list or the Inspector for any colour at all. Mirror keeps the opposite side matching. Grain sets the direction arrow that prints on each piece. The Realistic view lights the glass from behind; Photo under the lead shows the came over the picture, Photo through the glass shows both.
16. Came and print. Choose the came: lead 1/4" as the default, 3/16" on fine parts, 3/8" at the frame — any line can take its own size (Inspector → Apply to its run), and the Came tab counts sticks per size and checks that every side of the border carries the same edge came. Lead bends to about one and a half faces of radius (10 mm for 1/4"), zinc hardly at all, foil as tight as you like: a curve too tight for its came is flagged with the notches and slots to cut drawn on it, or eased with one click. Changing the edge came (U channel or H section) asks whether the band takes up the difference or keeps its glass. Print tab gives 1:1 PDF sheets with an assembly map, glass list and came-run sheet.

An illustrated manual is coming once the tool settles down; this list is the whole workflow until then.

Why designers fight their pattern software

Glass Eye 2000, the program most studios run, dates from the late 1990s and models a design the way a drawing program does: as a bag of lines that happen to touch. That is fine until the client wants the tulip a little taller. Now the four lines that met at the tip of the petal must all be moved to the same new point, the two pieces either side must be re-closed, the numbers re-issued, and the cut list re-run. A designer told us he spends a good part of every week doing exactly that.

The fix is a data model, not a feature. Here the pattern is a planar graph: junctions, the lead lines between them, and the pieces computed as the faces the lines enclose. Drag a junction and every line into it follows with a falloff; the pieces on both sides re-close by definition, because they were never stored. Add a line across a piece and it becomes two pieces, each inheriting the parent's glass. Delete a line and the two pieces merge and the leftover junction dissolves. Borders and shapes are inserted the same way - every line they cross becomes a junction - which is why a circle dropped onto a background becomes a real island with a real hole to bridge, not a picture of one.

Lead line, cut line and the heart of the came

H-section lead came comes in face widths from 3/16 inch (4.8 mm) up to 1/2 inch (12.7 mm), but the number that decides the cut is not the face - it is the heart, the web between the two channels, about 1/16 inch (1.6 mm) on lead and around 1/32 inch on copper foil. The glass sits in the channel either side of the heart, so each piece is cut half a heart smaller than the line on the cartoon. Three-blade pattern shears exist for exactly this reason: they remove a 1.6 mm strip (or 0.8 mm for foil) as you cut the paper pattern apart. Choose the came in the Came tab and the tool draws both views: lead lines for the layout board, cut lines for the pattern shears and the glass, and prints either at full size.

Came runs: fewest cuts, fewest joints

Watch a good glazier lead up a panel and the order is never piece by piece. The long lines go down first, each as one continuous length of came, and the short lines are cut to butt into them. Every place a came stops is a cut, a mitre, a joint and a solder bead on both faces, so a layout with thirty long runs is quicker and stronger than the same panel in ninety short ones. The tool works this out for you: at every junction it pairs the two lines that run most nearly straight through (lead will happily follow a bend of 30 degrees; zinc will not), chains them into runs, and reports the count, the total metres and the number of 1.83 m sticks to buy. The Came runs view colours each run and numbers it, and the printed came-run sheet lists them longest first - the order to lay them. Click any junction to change which pair runs through it when you know better than the geometry.

Questions from the bench

The panel was always lines. The pieces were only ever the light between them.