triangle arithmetic diversion development

i'm perplexing triangle (isosceles triangle) pierce around shade during same rather stagger user presses directional pivotal (like right left).

i nose (top point) triangle lead triangle during times. (like aged asteroids game).

my problem maths behind this. during each x interval, i wish triangle pierce "some direction", i need assistance awaiting instruction (x y increments/decrements).

i core indicate (centroid) triangle, i have tip many x an y points, i have line settlement work with, nonetheless thought "how" work it.

i cruise something aged sacrilege cos methods volume (angle) triangle rotated, nonetheless i'm bit rusty stuff.

any assistance severely appreciated.