/**
* @brief Sets the x speed.
* @param x_speed the x speed of the object in pixels per second
*/
void StraightMovement::set_x_speed(double x_speed) {
if (std::fabs(x_speed) <= 1E-6) {
x_speed = 0;
}
this->x_speed = x_speed;
uint32_t now = System::now();
// compute x_delay, x_move and next_move_date_x
if (x_speed == 0) {
x_move = 0;
}
else {
if (x_speed > 0) {
x_delay = (uint32_t) (1000 / x_speed);
x_move = 1;
}
else {
x_delay = (uint32_t) (1000 / (-x_speed));
x_move = -1;
}
set_next_move_date_x(now + x_delay);
}
angle = Geometry::get_angle(0, 0, (int) (x_speed * 100), (int) (y_speed * 100));
initial_xy.set_xy(get_xy());
finished = false;
notify_movement_changed();
}
/**
* @brief Sets the speed to zero.
*/
void StraightMovement::stop() {
double old_angle = this->angle;
set_x_speed(0);
set_y_speed(0);
x_move = 0;
y_move = 0;
this->angle = old_angle;
notify_movement_changed();
}
/**
* @brief Changes the direction of the movement vector, keeping the same speed.
*
* x_speed and y_speed are recomputed so that the total speed is unchanged.
* Warning: if x_speed and y_speed are both equal to zero, this function
* stops the program on an error message.
*
* @param angle the new movement direction in radians
*/
void StraightMovement::set_angle(double angle) {
if (!is_stopped()) {
double speed = get_speed();
set_x_speed(speed * std::cos(angle));
set_y_speed(-speed * std::sin(angle));
}
this->angle = angle;
notify_movement_changed();
}
/**
* @brief Changes the speed, keeping the same direction of the movement.
*
* x_speed and y_speed are recomputed so that the movement direction is unchanged.
*
* @param speed the new speed
*/
void StraightMovement::set_speed(double speed) {
if (x_speed == 0 && y_speed == 0) {
x_speed = 1;
}
// compute the new speed vector
double old_angle = this->angle;
set_x_speed(speed * std::cos(old_angle));
set_y_speed(-speed * std::sin(old_angle));
this->angle = old_angle;
notify_movement_changed();
}
/**
* \brief Sets the entity to be controlled by this movement object.
*
* This entity can be nullptr if your movement applies to something else than a map entity.
* However, some subclasses of Movement may require a non nullptr entity because they
* implement movements that depend on the map content (e.g. to handle the collisions).
*
* \param entity The entity to control, or nullptr if the movement should not be
* attached to a map entity.
*/
void Movement::set_entity(Entity* entity) {
Debug::check_assertion(drawable == nullptr, "This movement is already assigned to a drawable");
this->entity = entity;
if (entity == nullptr) {
this->xy = { 0, 0 };
}
else {
this->xy = entity->get_xy();
notify_movement_changed();
}
notify_object_controlled();
}
/**
* \brief Sets the drawable to be controlled by this movement object.
*
* This entity can be nullptr if your movement applies to something else than a drawable.
*
* \param drawable The drawable to control, or nullptr if the movement should not be
* attached to a drawable.
*/
void Movement::set_drawable(Drawable* drawable) {
Debug::check_assertion(entity == nullptr, "This movement is already assigned to an entity");
this->drawable = drawable;
if (drawable == nullptr) {
this->xy = { 0, 0 };
}
else {
this->xy = drawable->get_xy();
notify_movement_changed();
}
notify_object_controlled();
}
/**
* \brief Changes the movement of the entity depending on the direction wanted.
*
* This function is called when the direction is changed.
*/
void PlayerMovement::compute_movement() {
// compute the speed vector corresponding to the direction wanted by the player
if (direction8 == -1) {
// no movement
stop();
}
else { // the directional keys currently pressed define a valid movement
set_speed(moving_speed);
set_angle(Geometry::degrees_to_radians(direction8 * 45));
}
// notify the entity that its movement has just changed:
// indeed, the entity may need to update its sprites
notify_movement_changed();
}
/**
* \brief Chooses a new direction for the movement.
*/
void RandomMovement::set_next_direction() {
double angle;
if (get_entity() == NULL
|| max_radius == 0 // means no limit
|| bounds.contains(get_x(), get_y())) {
// we are inside the bounds (or there is no bound): pick a random direction
angle = Geometry::degrees_to_radians(Random::get_number(8) * 45 + 22.5);
}
else {
// we are outside the bounds: get back into the rectangle to avoid going too far
angle = Geometry::get_angle(get_x(), get_y(), bounds.get_x() + bounds.get_width() / 2, bounds.get_y() + bounds.get_height() / 2);
}
set_angle(angle);
next_direction_change_date = System::now() + 500 + Random::get_number(1500); // change again in 0.5 to 2 seconds
notify_movement_changed();
}
