unity-physicscore2d-stacking

Stable box stacking in PhysicsCore2D requires high friction (0.5-0.8), low restitution (0.0-0.1), aligned centers of mass, and slightly rounded box corners via PolygonGeometry.CreateBox with a radius parameter. Increase solver iterations for tall stacks and build bottom-up with settling time.

Trigger a domino chain by calling ApplyLinearImpulse on the first domino with a small horizontal impulse applied near its top. Space dominos at roughly half their height, use friction around 0.6, and ensure each domino is a dynamic body resting stably on a static shelf.

Stacks collapse from misaligned centers of mass, insufficient friction, too few solver iterations, sharp shape corners, or spawning the entire stack at once with overlapping bodies. Increase iterations to 8-16, raise friction, bevel polygon edges, and place bodies precisely without initial overlap.

Yes, but thin shapes like cards (e.g., 0.001 thickness) are stress cases requiring high friction (around 0.7), precise angular placement, and high solver quality. The CardHouse example demonstrates a 5-story structure of tilted thin rectangles balanced with horizontal connector cards.

Large stacks are expensive; the Pyramid example runs 1830 dynamic boxes as a stress test. Use sleeping for stable regions, static bodies for permanent structures, limit active collision pairs, and profile at your target stack size before shipping.