glVertex2f(ship.pos.x + v.x + a1.x, ship.pos.y + v.y + a1.y);
glVertex2f(ship.pos.x + v.x, ship.pos.y + v.y);
glVertex2f(ship.pos.x + v.x + a2.x, ship.pos.y + v.y + a2.y);
glEnd();
Vector3 forceVector = rb.netForce();
glColor3f(0, 0, 1);
glBegin(GL_LINES);
glVertex2f(ship.pos.x, ship.pos.y);
glVertex2f(ship.pos.x + forceVector.x, ship.pos.y + forceVector.y);
glEnd();