Ver. 3.7.9 - Lower memory use, faster large drawings, precise picking, a Drawing Check you can trust (2026/8/8) - Leathercraft CAD

✨ Highlights

• Memory use cut to under a third — 445MB down to 138MB just after startup, and the peak from 916MB to 151MB. The leather catalog now holds its images in an entirely different way

• Large drawings are workable again — on a 2,000-shape pattern, opening went from 113 seconds to about 4, and the wait after each edit from 1.45 seconds to 0.45

• Precise picking — the clickable area around a shape is now the same size at every zoom level, and grabbing an endpoint no longer drags the whole shape

• Drawing Check you can trust — four causes of false warnings fixed, and nothing is reported that the repair cannot fix

• Undo — one operation is now one undo, and a new option keeps the history within a memory budget

🚀 New Features & Enhancements

Memory and startup

• The leather catalog holds its images differently — until now, every leather image was embedded in the catalog's JSON file as a compressed image. That meant all of them were decoded into memory at every startup, and they accounted for most of what the app was holding. Images are now cached as PNG files outside the catalog and read only when they are needed. Memory just after startup falls from 445MB to 138MB, and the peak from 916MB to 151MB.

• The catalog loads faster — the startup step that reads it went from about 4.1 seconds to about 0.16.

• Browsing the whole catalog costs far less — images for brands you are no longer looking at are released, so browsing every leather adds about 14MB rather than 341MB.

• Dialogs are created when opened — fourteen of them are no longer built at startup, cutting memory used at startup by about 33%.

• The undo history can trim itself — a new option keeps the undo history within available memory while guaranteeing a number of steps you can always go back. This is the fix for long sessions consuming memory until the machine stalls.

Performance

• Opening a large drawing — intersections with the whole drawing were recomputed as each shape was added, so the cost grew with the square of the shape count. On a 2,000-shape pattern this went from 113 seconds to about 4.

• The wait after each edit — 1.45 seconds down to 0.45 on the same pattern.

• Drawing Check runs about 5 times faster (1.9 seconds to 0.39).

• Clicking a grouped shape no longer costs about 1.4 seconds.

• The hourglass now means something — it stays up until the drawing is actually on screen, so there is no longer a stretch where the cursor is back but the canvas is still blank. It also appears during the whole-drawing tidy-up.

Selection and handling

• The pick radius no longer changes with zoom — the clickable area around a shape used to shrink to roughly one pixel when zoomed out to a tenth, and grow to some 53 pixels when zoomed in. It is now a steady ~12 pixels at any zoom, and where two lines overlap the nearer one is reliably the one you get.

• Endpoints can be grabbed and moved — re-grabbing an endpoint you had already moved used to drag the whole shape, and an endpoint you had not yet hovered could not be grabbed at all. Fixed for lines, Bezier curves and arcs.

• Zoom out to one tenth — enough to see a large pattern whole.

Drawing Check

• The banner shows the warning count.

• Lines that are meant to be at an angle are exempt — a dimension guide is drawn perpendicular to the shape it marks, so on a curve it is legitimately a fraction of a degree off horizontal. That is no longer reported as a drawing error.

• The check and the repair now cover the same ground — nothing is flagged that the repair button cannot fix. On a real 3,848-shape pattern, 136 warnings went to zero in a single tidy-up run with the geometry unchanged.

Undo

• One operation, one undo — chamfering four corners, and moving or copying by a set distance, each go back in a single step.

• Runs are collapsed — rotation, scaling, font size changes and tracing image adjustments made with the wheel or keys are undone as one operation.

• Pending changes are visible — while number boxes are in use, the app shows that there are changes not yet in the history.

Elsewhere

• Arithmetic in the shape size dialog — its number boxes now accept expressions, like the other numeric fields.

• Repair commands are separated from editing commands in the right-click menu.

• Duplicate removal is reported — when opening a project removes duplicate shapes, the app now says how many. It used to happen silently, which is why a freshly opened file could ask to be saved.

• Creating or opening a project now returns from the leather simulator to selection mode and clears "Hide drawing lines".

• The options screen layout has been tidied up.

🐛 Bug Fixes

Drawing Check

• Fixed shapes that share an endpoint being flagged in red as crossing each other.

• Fixed lines shorter than 0.2mm being reported as a gap even when correctly connected.

• Fixed overlaps involving arcs or Bezier curves being reported but impossible to repair.

• Fixed the whole-drawing tidy-up not fixing problems that the right-click repair could fix.

• A T-junction onto a slanted line is now closed while keeping that line's angle intact.

• Fixed the overlap warning stating a cause it had not actually tested for.

• Fixed warnings starting out invisible depending on when the check finished.

• Fixed the two ends of a single shape being merged into one connection point.

• Overshoot is now judged in millimetres rather than by an internal parameter.

Selection and snapping

• Fixed shapes being pulled around by points other than the one you grabbed when dragging several shapes.

• Fixed a line being moved by its far endpoint snapping to something while you dragged the near one.

Undo

• Fixed a drag that moved nothing still being recorded in the undo history.

• Fixed merely selecting a grouped shape being recorded in the undo history.

• Fixed the modified flag not being restored after undo or redo, which let the app close without asking to save — work could be lost that way.

Tracing and elsewhere

• Fixed a tracing pivot drag not being reflected in the coordinate boxes, which sent the image back to its old position on the next edit.

• Fixed canvas settings not being restored after a batch of stitch holes was drawn, which could affect later drawing.