A shape with a top bevel seen through a 3-D scene drew flat. Fitted to
PowerPoint's export of the bevel presets on a solid fill with the default
three-point light rig and matte material, DeckCraft now lights the face
and a band as wide as the bevel inside the outline as surfaces: Lambert
light from the upper left (azimuth 240, 45 degrees up), c * (0.453 +
0.731 * n.L) + 14.7 per channel, the band's normal tilting outwards by
the profile's slope (quarter circle by default, straight for angle).
Within about 15 grey levels RMS of PowerPoint on the circle bevel; other
profiles use the circle's, pictures get light and dark veils, and other
light rigs and materials (and anything without a scene) stay flat.
Wild synthetic set: bevel presets slide 5.20 -> 2.48, materials/rigs
13.25 -> 12.73.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>