Members that carry end cuts are placed as Outline2D profiles — a 2D polygon extruded along a local axis — rather than rotated boxes. The engine computes the cut polygon (the digital equivalent of SmartBuild's Cuts[] records) and the renderer just extrudes it.
Also called: birdsmouth · plumb miter · joinery · rake board miter · seat cut
- 1Top chords are 2x trapezoids with plumb ends and an optional heel seat, so two chords meet at a peak without occupying the same wood.
- 2Webs are built as 2x4 rectangles then clipped to the chord half-planes (Sutherland-Hodgman) so a web's corners cannot sit inside a chord.
- 3Rake boards are drawn as profiles whose top edge follows the roof plane, plumb-mitered at the apex into a clean V and level-cut at the eave so the return lands exactly on the fascia's outer face, top line and bottom line.
- 4The ridge cap is a bent profile following both roof planes, standing clear of the steel, with its ends buried mid-thickness of the rake boards.
- 5Addition rafters carry plumb cuts at the ridge or ledger, seat-and-heel birdsmouths over every beam, and a plumb tail cut at the fascia.
Members drawn as boxes that simply overlap look like a pile rather than a building: the first truss rendered its webs and both chords as one flickering lump, and rake boards met the fascia with a visible lip and a mismatched bottom edge at every corner. Pieces are now cut where they meet — mitred rake joints, plumb-cut tails at the eave, chords seated on their bearing — so the corners close the way they close on site. It matters past appearances, because a customer studying a render decides whether to trust the whole quote on whether the corners look right.
- Square-butted members occupying the same wood, which reads as flicker and as a lie about how it is built.
- Trim ends that overshoot or leave a lip at every corner.
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