Tiny4k - Charity Crawford -bouncing Spinner Tus...

static const float BOUND_X = 0.9f; // screen coordinate range [-1,1] static const float BOUND_Y = 0.7f;

We keep the bounce logic : a 2‑D position vector and a 2‑D velocity that are reflected at the screen bounds. Tiny4k - Charity Crawford -Bouncing Spinner Tus...